MANAGEMENT OF ICE STORM DAMAGED STANDS

PRODUCTION TEAM

Research and draft ing

Bruno Boulet, F.Eng.*, Direction de la conservation des forêts, MRNFrançois Trottier, F.Eng., Direction de l’assistance technique, MRNGabriel Roy, F.Eng., Direction de la recherche forestière, MRN

Technica l support

Léo Beaudoin, F.Eng., Direction régionale de Montréal, MRNGisèle Bélanger, F.Eng., Service de mise en valeur des forêts privées, MRNMichel Chabot, F.Eng., Direction de la conservation des forêts, MRNKen Dubé, F.Eng., Groupement forestier coopératif de Saint-FrançoisLuc Gaboriault, F.Eng., Direction régionale de l’Estrie, MRNGérald Landry, F.Tech., Service de mise en valeur des forêts privées, MRNConrad Merette, F.Tech., Direction de l’assistance technique, MRNÉmile Aubin, F.Tech., Direction de la conservation des forêts, MRNPierre Morin, F.Eng., Service des inventaires forestiers, MRNJosée Pâquet, Geogr., Service de mise en valeur des forêts privées, MRNYves Philibert, F.Eng., Fédération des producteurs de bois du QuébecSylvain Rajotte, F.Eng., Société de gestion forestière Des Sommets

Scient i f ic rev is ion

Christian Godbout, F.Eng., Direction de la recherche forestière, MRNMichel Huot,F.Eng., Direction de la recherche forestière, MRNGuy Prégent, F.Eng., Direction de la recherche forestière, MRNMarcel Prévost, F.Eng., Direction de la recherche forestière, MRNDenis Robitaille, F.Eng., Direction de la recherche forestière, MRN

Trans lat ion

Christine Gardner and Réjeanne Bissonnette

Distr ibut ion

Direction des communicationsMinistère des Ressources naturelles5700, 4e Avenue Ouest, B.302Charlesbourg (Québec) G1H 6R1Telephone: (418) 627-8600

1 800 463-4558Internet: www.mrn.gouv.qc.ca

Cover page photo

Severely damaged sugarbush on a rich site, near Kingsey Falls (1998). After two growth seasons,maple tree restoration is slow but encouraging. (Photos: Lina Breton)

To join the author: Telephone: (418) 627-8642 (ext. 4029)Fax: (418) 643-2368E-mail: [email protected]

This document is also available in French, under the title L’aménagement des peuplements forestiers touchéspar le verglas.

This project was financed jointly by the Government of Canada and the Gouvernement du Québec.

© Gouvernement du QuébecMinistère des Ressources naturellesLegal Deposit – Bibliothèque Nationale du QuébecISBN: 2-550-35993-3 Distribution code: 2000-3070

TABLE OF CONTENTS

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

GLOSSARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

1. THE VIGOUR, QUALITY AND VITALITY OF DAMAGED TREES . . . . . . . . . . . . . . . . . . . . . . . . .15

1.1 Stem classification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15

1.2 Severity of damage and risk of tree mortality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18

2. MANAGEMENT OF DAMAGED FOREST STANDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23

2.1 The objectives of treatments in damaged forests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23

2.2 Salvage priorities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24

2.3 Silvicultural work in damaged stands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26

2.3.1 Tolerant hardwood stands (other than red maple) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28

2.3.2 Red maple stands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30

2.3.3 Maple stands managed for sap production . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31

2.3.3.1 Sugarbush management method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32

2.3.3.2 Restoration of sugarbushes destroyed by the ice storm . . . . . . . . . . . . . . . . . .34

2.3.4 Mixed stands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37

2.3.5 Other types of stands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38

2.3.5.1 Trembling aspen stands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38

2.3.5.2 Pre-merchantable hardwood plantations and stands . . . . . . . . . . . . . . . . . . . . . . . . .38

2.3.5.3 Softwood stands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39

2.3.5.4 Conifer plantations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43

2.4 Operations related to the salvage of damaged trees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45

2.4.1 Hardwood stands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46

2.4.2 Softwood plantations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48

3. THE EVALUATION METHOD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49

3.1 Multiple-stage survey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49

3.2 Appropriate sample size and survey period . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49

3.3 The variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52

3.4 Data compilation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54

CONCLUSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57

SELECTED REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59

LIST OF TABLES, FIGURES AND APPENDICES

Table 1 Stem classification by vigour and quality ........................................................................................15

Table 2 Loss of vigour and quality in ice-damaged trees.........................................................................16

Table 3 Mortality rate of maple trees by level of damage in 1998 ....................................................20

Table 4 Visible indicators of vitality and probable recoveryin ice-damaged trees .................................................................................................................................21

Table 5 Salvage priority order in ice-damaged stands...............................................................................26

Table 6 Number of sample points to be established by stand area...................................................51

Table 7 Salvage program established accordingto the value of the wood at risk............................................................................................................57

Figure 1 Key for classifying hardwood stems by vigour and quality.....................................................17

Figure 2 Mortality rates of maple trees, estimated on the basis of four critical residual crown thresholds (% Crc98) and the average percentage of canopy loss in the stand.......................................................19

Figure 3 Harvesting methods recommended by basal area to bepreserved in tolerant hardwood stands ............................................................................................27

Figure 4 Decision key for managing merchantable tolerant hardwood stands .............................28

Figure 5 Decision key for managing young ice-damaged hardwood stands ..................................40

Figure 6 Steps in assessing damage, formulating appropriate silviculturalrecommendations and monitoring the recovery of ice-damaged stands ..........................50

Figure 7 Sample point and sample plots established to estimatecrown cover, stand density and advance-growth.........................................................................53

Appendix 1 Residual crown of ice-damaged trees...............................................................................................61

Appendix 2 Bole deformations in ice-damaged trees ........................................................................................62

Appendix 3 Assessing the severity of bole wounds on ice-damaged trees..............................................63

Appendix 4 Characteristics of species: heartwood resistance to decay,shade tolerance, life span, growth rate and potential use by wildlife..............................64

Appendix 5 Ice damage survey form ..........................................................................................................................65

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INTRODUCTION

The ice storm that swept over southern Québec from January 5 to 9, 1998, damagedapproximately 1.8 million hectares of forests, mostly (92%) privately owned. The levelof damage varied, but in some stands it was such that restoration and salvage work

are now needed. Aerial surveys suggested that an estimated 567,737 hectares of forests(32% of the total) had been severely damaged. Young forests, which literally collapsedunder the weight of the ice, accounted for 73,601 hectares, or 4% of the damaged area (7).Damage was light to moderate in the remaining stands (64% of the area), and the trees willrecover naturally in the coming years. A forest survey carried out in the spring of 1998 showedthat severely damaged trees accounted for nearly 40% of all standing timber (around 55 m3/ha)in Montérégie, 25% in the Eastern Townships and 19% in the Ottawa Valley (19)1.

The main concern at this point is salvaging the wood going to waste. However, giventhe extent of the damage and the large volume of timber at risk, it would be preferableto spread salvage operations over a period of time, to avoid overproduction of timberand saturation of certain markets (19). Possible time frames vary according to speciesand type of products and we thus have some leeway. For example, it is possible to waitone year, three years or even five years before salvaging timber, depending on whether itwill be used for veneering, sawing or pulp or as fuel (5).

It is also important to restore to production any severely damaged stands containingpre-commercial trees or trees with a lower market value. If no action is taken, such standswill have very little chance of recovery, since there are not enough remaining crop treesper hectare to guarantee optimal production of quality timber.

The stability of certain stands, especially tolerant hardwood stands, is also threatenedby the severity of the damage. When the forest canopy is reduced, the amount of lightpenetrating to ground level increases, possibly compromising the survival of young mapletrees, especially seedlings2, and promoting the growth of undesirable species such asbeech, fir, aspen and raspberry. Increased light and heat also heighten the risk of trunksunscald as well as soil and rootlets drying. It may lead to productivity losses.

Adventitious sprouts and buds may form on the lower part of the crown of damagedhardwoods, which would result in the downgrading of logs earmarked for veneering. Inaddition, broken main branches allow discoloration and decay fungi to penetrate the tree.The nectria canker, Neonectria galligena (Braz.), Ross. and Sam., can also propagatethrough small cracks in the bark on the branches and trunks of icefallen yellow birchtrees, eventually reducing the quality of the timber (5).

If the stands are to recover, the root systems of the trees must be protected, especiallyduring salvage operations. Before logging begins, the condition of the stand3 and the treesslated for priority salvaging must be assessed as accurately as possible. A survey method

1 The figures in brackets refer to the bibliography.2 Current year seedlings, especially sugar maple and yellow birch ones, are the most vulnerable, because they are rooted

in the surface layer. To become established and survive, they need a plentiful supply of water and shade.3 A stand condition assessment establishes tree vigour, which often depends on disturbances prior or subsequent to the ice

storm. Tree vigour must be taken into account when selecting the trees to be salvaged in priority, especially if the goal istimber production.

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for damaged stands is proposed in this document. By assessing the damage, it is possibleto estimate the volume of timber to be harvested for each intended use, and to selectthe best management method. Such estimates are especially valuable when it comes tomarketing the timber, since it may be difficult if not impossible to sell lower quality woodin the short term.

This document conveysimportant information for themanagement of ice-damagedstands. The first section containsa glossary that defines the termsas they are used in this doc-ument. Subsequent sectionsexplain the basic notions requi-red to assess tree vigour, timberquality and survival chances, andpresent management guidelinesin the form of summary tablesas well as simple and practicaldecision-making keys. The keyshave been designed to help forestadvisors selecting the best treat-ment for each stand. The textcontains a number of photo-graphs illustrating the mostcommon problems and the long-term impacts observed in sugar-bushes in the Lanaudière regionafter the 1983 ice storm.

Sugarbush severely damaged by the 1998 ice storm. Maple advance-growthis poor, and the stand has been invaded by hay-scented ferns. If logging isnot planned carefully, the ecological stability of the stand will be at risk.

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Broken boleTree that is broken below the crown orwhose bark has been torn off, even if theupper part is still alive (see Appendix 2,Figure 2.4).

Broken leader pruningPruning of the leader or the highest orsecond-highest internode of a crown-damaged conifer. This treatment isperformed in plantations to preservethe quality of lumber to be harvested inthe future (see sections 2.3.5.4 and 2.4.2).Applications: This type of pruning, per-formed with shears, promotes the growthof a lateral branch to replace the lostterminal leader, thus correcting any sig-nificant curvature in trees to be preservedas crop trees in the plantation.Recommendations: This treatment is car-ried out only on young pre-merchantabletrees more than 1.5 m high that willeventually make up the stand.

CoppicingOperation that consists in cutting backto approximately 5 cm from the groundyoung leaning or icefallen hardwoodtrees with a diameter at stump height(dsh) of < 15 cm, either before budbreakor after the leaves have fallen.Applications: This operation promotesthe formation of new stump sprouts.After a year, three sprouts should beselected as close to the ground as pos-sible. The most vigorous stump sproutwill finally be kept to become the croptree (see section 2.4.1).

Recommendations: This treatment isappropriate for hardwood trees, includ-ing red maples, oaks, ashes, walnuts andbasswoods, which naturally producestump sprouts after cutting. Good resultsare not always achieved with yellowbirch and sugar maple trees that aremore than 10 cm in diameter.

Crop hardwood treeStraight or slightly leaning tree with adbh of between 10 cm and 24 cm, thatcontains at least one defect-free log andwill be ready to be harvested in the nextlogging cycle.

Defective hardwoodA tree with a dbh of ≤ 24 cm, containingno defect-free logs and consequentlydestined for pulp, heating or pallet pro-duction (see section 1, Table 2).

Defective softwood(a) Mature conifer with heart rot that

still contains one saw log and thathas to be salvaged quickly due tothe high risk of windthrow.

(b) Uprooted, leaning or icefallen conifercontaining at least one merchantablelog.

(c) Merchantable conifer other than awhite or red pine that has beenbroken at a height where the diam-eter is > 6 cm and that has to besalvaged due to the high risk of decay.Large crown-damaged or delimbedwhite and red pines are much less

GLOSSARY

WarningSome of the terms and phrases in the glossary

have a specific meaning in this document.

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likely to deteriorate (see Appendix 4),and should be preserved as seedtrees in natural stands or as qualitysoftwoods in plantations. However,they should be harvested in priorityduring the next thinning cycle.

Icefallen treeTree leaning at an angle of morethan 70o from the vertical position (seeAppendix 2, Figure 2.3).

Improvement cuttingRemoval of less desirable or ice-fallentrees in a stand that is past the saplingstage, to improve its composition andquality.

Large seedlingsA hardwood or conifer that is 3 or 4years old, with an average height ofbetween 40 cm and 60 cm, cultivatedin a nursery for use in reforestation.Recommendations: Large seedlings areused for reforestation of high-qualityforest sites and abandoned farm landswhere herbaceous competition is strong,as well as to fill in stands that weredamaged or destroyed by the ice storm(see sections 2.3.5.4 and 2.4.2).

Leaning treeTree bent at an angle of between 30o

and 70o (see Appendix 2, Figure 2.2).If the angle is greater than 40o, the treehas no chance of returning to a verticalposition, especially if epicormic sproutshave formed on the trunk.

Lopping and scatteringThis operation involves reducing thefallen branches to chips which are spreadover the ground as evenly as possible. Itis beneficial for the residual stand, sinceit improves soil quality and stimulatesthe growth of microflora and microfauna(see section 2.4.1).

Mini-strip cutting

This type of harvest is carried out onabandoned farm lands and in youngstands damaged or destroyed by the icestorm, prior to reforestation with com-mercial hardwoods.

Recommendations: Strips 4 m wide and8 m apart are clear-cut in an east-westdirection. Hardwood or white pineseedlings are then planted along thenorthern side of the strips, where theyobtain maximum sunlight and have abetter chance of dominating the com-peting vegetation.

Sugarbush severely damaged by the 1998 ice storm,where the wood at risk should be partially salvaged.Tree recovery should be monitored. In this case, loggingshould be spread over a period of time, and the fate of thestand should not be decided too quickly.

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Partial salvage cuttingOperation in which only dead and veryweak trees are harvested in moderatelydamaged, average density stands and inseverely damaged dense stands (priori-ties 1, 2, 3, 4 and 5 from Table 5).Applications: The residual stand facesan uncertain future, and should have abasal area of at least 12 m2/hectare.This threshold may be extended to16 m2/hectare for certain types of stand(see sections 2.3.1, 2.3.2 and 2.3.3).Recommendations: If the number oftrees to be salvaged in priority is suchthat the stand basal area would fallbelow the minimum recommendedthreshold, salvage operations should belimited to the most severely damagedsectors only. Salvaging of dead treesshould also be spread over a longerperiod, and, in the short term, only haulingtrails should be cleared, opening upaccess to the whole stand. This helpslimit machinery movements and poten-tial injury to the lower part of the boleand the roots of residual trees. Salvageoperations should also be spread over alonger period if the markets becomesaturated (9). If the trees have survivedthis long, it is possible to wait for a fewmore years in order to make an informeddecision regarding the management ofseverely damaged stands, whose recoverydepends on the age and vigour of thetrees and on the quality of the site.

Quality hardwoodA tree containing at least one defect-freelog (see section 1, Table 2). A qualitytree has the following features (1):• dbh of ≥ 24 cm• total length of ≥ 1.8 m• volume reduction due to defects, estim-

ated on the next-to-last quality face,of 60% or less

• Length of the defect-free next-to-lastquality face ≥ 60 cm.

Quality softwood

(a) Healthy conifer or conifer with noobvious signs of decay, containingat least one saw log.

(b) Conifer broken at a height where thebole diameter was less than 6 cmand that is less likely to deteriorateas a result of decay.

(c) Young softwood grown in a planta-tion, straight or bent over to anangle of less than 30o, brokenunder the leader or the highest orsecond-highest internode, but thatnevertheless has a good chanceof recovering and maintaining itsquality for lumber production (seesection 2.3.5.4).

Residual crown

The portion of the crown that survived the1998 ice storm. It is estimated visually,based on the number of twigs andadventitious branches that have grownsince the storm (see Appendix 1).

Sanitation cutting

Treatment that consists in cutting downdead, dying and severely damagedtrees in order to prevent infestations ofsecondary insects, discoloration anddecay fungi, and other diseases suchas nectria canker (Neonectria galligena(Bres.) Ross. and Sam.).

Applications: This type of treatmentshould be carried out in moderatelydamaged stands where trees likely todeteriorate before the next loggingcycle account for no more than 30% ofthe stand basal area. The volume oftimber to be harvested is generally low(≤ 20 m3/hectare).

Recommendations: Whenever possible,≤ 20% of the initial stand basal areashould be harvested, following the prio-rity order shown in Table 5 (section 2.2)

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and in accordance with the appropriateminimum density threshold for the typeof stand involved (20 m2/hectare or22 m2/hectare, see section 3.4).

Severe bole wound

A wound is said to be severe if thesapwood is exposed over more than25% of the tree’s circumference (morethan one exposed face). If the sapwoodis exposed over 50% of the circumfer-ence, this counts as two severe bolewounds (or two exposed faces), etc.Where branches have been broken off30 cm or less from the bole, the dia-meter of the stub is calculated as a per-centage of the bole’s circumference, atthe point of attachment (see Appendix 3).

Severely damaged stand

Woodlot all or part of which was severelydamaged by the ice storm and whichcontains wood at risk. A tolerant hard-wood stand is severely damaged if theweak hardwood basal area (BA) is ≤ 30%(see sections 2.3.1, 2.3.2 and 2.3.3).In the case of transition stands, 30% ofthe BA must be composed of weakaspens (see section 2.3.5.1) and, in thecase of softwood stands, a similar per-centage must be composed of defectivetrees (crown-damaged trees) (see section2.3.5.3). Lastly, in mixed stands, 30% ormore of the BA should be composed ofaspens or other weak hardwoods and ofcrown-damaged or defective softwoods(see section 2.3.4).

Recommendations: Woodlot ownerswhose trees were severely damaged mayobtain technical assistance (timbermarking and logging) for the salvage ofcommercially valuable wood at risk andrestoration of their woodlots.

Shelterwood cutting

This involves, in the first instance, harv-esting between 30% and 50% of thetotal volume of timber from a given sitein order to encourage the growth of anew stand of equal or superior quality.

Applications: This type of cutting is suit-able where portions of stands have beendestroyed or severely damaged and arenot regenerating properly. It shouldbe applied only in sugarbushes, othertolerant hardwood stands (see sections2.3.1 and 2.3.3), and conifer stands inwhich significant portions of the canopyhave been destroyed (see section 2.3.5.3).

Recommendations: This treatment canbe applied evenly to the whole of thedamaged area, or to patches in evenly-structured stands where severe damageis limited to certain well-defined areas.

Soil amendment

Spreading of fertilizers, ash, lime orsludge on the ground, to help dying trees.

Recommendations: This type of inter-vention is not recommended in thefirst three years, first because it is notnecessary (see section 2.4.1), andsecond because an amendment carried

In many areas where damage was light to moderate, the ice storm tendedto eliminate diseased or defective trees that had no future in the stand.

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out without a chemical analysis of the soiland leaves may actually be harmful tothe trees and to the stand as a whole (15).

Straight tree

Tree that is vertical or leaning at anangle of less than 30o (see Appendix 2,Figure 2.1).

Total salvage cutting with advance-growthprotection

This operation consists in harvestingmerchantable timber while providing thebest possible protection for young treesof desirable species in stands destroyedby the ice storm. The trees left standingshould be evenly spaced and sufficientlyplentiful for the site to be restored toproduction quickly.

Applications: This treatment is suitablefor tolerant hardwood stands, maplestands, mixed stands and softwood standsin which advance-growth is sufficient andevenly distributed.

Recommendations: Care is requiredhere, especially in young stands on goodsites. Although the damage may besevere, forest advisors may suggest apartial salvage cut and then monitor thestand’s development over a number ofyears. Total salvage cutting should only berecommended if the trees show no signsof recovery after that period (see section1.2, Table 4, and section 2.3.3.2).

TrimmingAn operation that involves removingbroken branches and pruning branchesthat pose a threat to the safety ofhuman beings or property.

Recommendations: For economic reasons,systematic trimming is not recommended,except where the trees are located alongroads or near constructions. Crownwounds are not exposed to moisture, andthus, do not promote decay. However,scratches on the lower part of the trunkor the roots are conducive to fungal

Sector of a young sugarbush destroyed by ice. The advance growth must be protected when salvaging the timber.

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infections (4) (5). Heavy equipment canalso cause serious damage to the shallowroots of maple trees, especially where theground is soaked (9) (see section 2.4.1).

Two-step total salvage cutting

This operation involves, in the firstinstance, harvesting at least 50% of thewood at risk (dead or dying trees, residualcrown ≤ 10%, and uprooted or icefallentrees), and then waiting at least five yearsbefore the final cutting.

Applications: This type of salvage cuttingshould be applied only in hardwood standswith a high percentage of severely dam-aged or dead red maple trees, wheretrees that have retained more than 20%of their branches account for less than16 m2/hectare (see section 2.3.2).

Recommendations: The two-step totalsalvage cutting allows the wood at riskto be sold over a period of time, thuspreventing market saturation, especiallyfor low quality timber. The rest of the standis harvested once the market capacityhas been confirmed. Dead trees canalways be sold for heating purposes,even if their bark has become detached.

Unsalvageable hardwood

(a) Young, severely leaning or icefallentree of pre-commercial size.

(b) Weak, pulp-quality hardwood thatcannot be salvaged profitably.

Unsalvageable softwood

(a) Mature softwood with heart rot,containing no saw logs or pulp logs.

(b) Young uprooted, leaning or icefallenpre-merchantable conifer, grown ina plantation.

(c) Young conifer broken under thesecond-highest internode or at aheight of ≤ 2.5 m (see section2.3.5.4).

Viable treeIce-damaged tree whose short-termsurvival is not threatened (see section1.2, Table 4).

Vigorous aspenAn aspen that has retained ≥ 60%of its crown. The threshold is highbecause decay can cause the timberto deteriorate quickly, especially wherethe bole has been severely damaged(see section 1, Table 2 and Appendix 4).

Vigorous hardwoodA tree other than an aspen that hasretained ≥ 20% of its crown and whosebole is either straight or leaning slightly,with no more than one significant wound.Such trees are likely to survive and pro-duce lumber in the next logging cycle4

(see Appendices 1 and 3, and Figures 2.1and 2.2 in Appendix 2).

Weak aspen(a) Aspen that has retained less than

60% of its crown or with at least twosignificant bole wounds, unhealedcracks, cankers, heart rot fungi orroot rot fungi.

(b) Uprooted tree, severely leaning tree,icefallen tree or a tree broken belowthe crown that is likely to die in theshort term. Growth and quality willdecline considerably in the comingyears.

4 The normal interval between thinning may have to be extended from 15 to 20 years, to ensure that the volume harves-ted does not exceed the periodic increment. For the sugar maple, the current annual increment in terms of basal areavaries from 1.7% to 2.6% (10).

13G L O S S A R Y

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Weak hardwood

(a) Tree other than an aspen that hasretained less than 20% of its crownor with at least two severe bolewounds, unhealed cracks, cankers,heart rot fungi or root rot fungi.

(b) Uprooted tree, icefallen tree or atree broken below the crown that islikely to die in the short term, or adying tree that has retained less than20% of its crown. A weak hardwoodwill grow very slowly in the comingyears, and may even die before thenext cutting cycle4. It will provide poorquality timber if harvesting is delayed.

Wood at risk

Wood from merchantable hardwoods andsoftwoods that were killed or weakenedby the ice storm. In salvage logging,the dead and dying trees should beharvested first, but decisions regardingthe fate of the trees that have survivedbut face an uncertain future should bepostponed. Robust crop trees and qualitytrees should be protected (see Tables 4and 5).

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15C H A P T E R 1

THE VIGOUR, QUALITY AND VITALITYOF DAMAGED TREES

1.1 STEM CLASSIFICATION

The method used to classify hardwoodand softwood trees damaged by the icestorm is derived from the method currentlyused for selection cutting in hardwoodstands (11), based on tree vigour and qual-ity (Table 1). As we know, the ice storminflicted significant crown damage and, insome cases, caused severe wounds to treeboles, thus reducing both vigour and quality.

A tree’s ability to recover from its woundsdepends not only on the severity of thedamage, but also on its pre-storm vigour.The classification shown in Table 2 allowsfor adjustment of current vigour and qualityaccording to the damage suffered as aresult of the ice storm. It can therefore beused to classify trees when surveying adamaged stand or selecting trees whichshould be harvested first.

TABLE 1 STEM CLASSIFICATION BY VIGOUR AND QUALITY

VIGOROUS HARDWOOD WEAK HARDWOOD SOFTWOOD

Quality Defective Quality Defective Quality Defective

I II III IV V VICLASSES

Grade I yellow birch downgraded following the 1998 icestorm (category III s) and to be salvaged in priority.

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Grade I sugar maple to be preserved as crop tree despitesevere damage suffered in 1998.

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16C H A P T E R 1

T H E V I G O U R , Q U A L I T Y A N D V I T A L I T Y O F D A M A G E D T R E E S

≥ 60%

High

Straightor

leaning

None

No

Icefallenor

uprooted•

None

No

≤ 25%(one face)

No

> 25%(2 facesor more)

Yes

≤ 25%(one face)

No


Yes

Straightor

leaning

≤ 25%(one face)

Yes

Brokenunder the

crown


Yes

I

I

II

III

IV

V

V

VI

III s / IV s

III s / IV s

IV s

III s

IV s

VI s

VI s

VI s

I

III s

II

III

IV

V

V

VI

III / IV

III s

II

III

IV

VI s

VI

VI s

I

III s / IV

II

III

IV

V

V

VI

III / IV

III s

IV

III

IV

VI s

VI

VI s

III s / IV

III s / IV s

IV

III s

IV

VI s

VI s

VI s

III s / IV s

III s / IV s

IV s

III s / IV s

IV s

VI s

VI s

VI s

41% - 60%

High or moderate

Straight or leaning

21% - 40%

Low or moderate

Straight or leaning

≤ 20%

Low or nil

TABLE 2 LOSS OF VIGOUR AND QUALITY IN ICE-DAMAGED TREES

CROWN:RESIDUAL

CROWN

ABUNDANCE

OF TWIGS

BOLE:DEFORMATION

WOUNDS

% OF

CIRCUMFERENCE

BROKEN TOP

DIAM. ≥ 6 CM

(SOFTWOOD)

VIGOUR BEFOREICE STORM

Quality hardwood I

Quality aspen I

Defective hardwood II

Quality hardwood III

Defective hardwood IV

Quality softwood V

Quality V pine

Defective softwood VI

VIGOUR AFTER ICE STORM

DESCRIPTION SEVERITY OF DAMAGEOF DAMAGE LIGHT MODERATE HEAVY SEVERE

s.Birch, aspen and softwood trees for priority salvaging. The vigour of straight class V red and white pine trees that haveretained ≥ 20% of their crown is not reduced since their quality for lumber production is not at risk.

• In the case of severely leaning or icefallen trees, the updated vigour classes are the same regardless of the percentageof residual crown.

17C H A P T E R 1


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A grid is also used to classify standinghardwoods by lumber production potential.The on-site procedure used to establish treevigour and stand potential is summarizedin Figure 1, which combines the notionspresented in Tables 1 and 2 as well as inAppendices 1, 2 and 3. Forest advisorsshould also consult the guide entitled

Classification des tiges d’essencesfeuillues – normes techniques (1). Theproposed system can be used to classifystems according to their quality (A, B, Cor D), and to calculate gross timber volumedepending on whether the logs are intendedfor veneering5, sawing or pulping.

FIGURE 1 KEY FOR CLASSIFYING HARDWOOD STEMS BY VIGOUR AND QUALITY

5 It should be remembered that logs measuring 24 cm at the small end qualify for veneering, and those measuringabout 35 cm at the small end are generally of the best quality. Good cross-cutting can eliminate certain defects toallow the logs to meet standards. Yellow birch, white birch, trembling aspen, sugar maple, black cherry, white ash andAmerican basswood are the main species sought by the industry.

Class

II

Class

III

Class

IV

Vigoroustree*

Class

I

Residual crown≤20%,

severe wound(2 faces of bole) or

icefallen oruprooted tree

Wood atrisk

Viable tree(> 5 years)

showing signsof recovery

Weaktree*

dbh

≥24 cm5

Sawtimber

Class

III

Class

IV

dbh

≥24 cm5

Sawtimber

Crop treefor sawing

YES

YES

YES

NO

NO

NOYES

YES

YES NO

NO

NO

YES

YES

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18C H A P T E R 1


1.2 SEVERITY OF DAMAGE ANDRISK OF TREE MORTALITY

The staff at the Ministère des Ressourcesnaturelles has created a network for moni-toring the development of sugarbushesdamaged by the January 1998 ice storm.The network is composed of 67 circular plotsmeasuring 0.04 hectares each, distributedthroughout the affected regions andrepresentative of the different levels ofdamage. They were selected to:

• establish the relationship betweendamage measurements obtained onthe ground and those obtained fromaerial surveys;

• measure the effects of the ice stormon the growth and vigour of trees,saplings and seedlings;

• estimate the anticipated short andmedium term tree mortality rate;

• establish the ecological characteris-tics favourable to the recovery ofsugarbushes and other tolerant hard-wood stands;

• validate proposed silvicultural treat-ments to promote woodlot recovery.

A preliminary analysis of data obtainedfrom the network was used to establishfour sugarbush mortality scenarios. Thehypothesis is that a tree’s resistance to anice storm can be expressed as a percent-age of the critical residual crown (%CRC)or the threshold below which the tree isunable to recover properly. In other words,the percentage of residual crown providesa visible indicator of vitality, wherethe critical value varies according toconditions in the tree’s environment.

For example, a young maple tree grow-ing on a rich and nutritious site will probablyrecover even if it had a residual crown ofonly 20% in 1998. On the other hand, anold maple tree growing in shallow, dry soilwould be likely to die even if it retained40% of its crown. The four scenarios areillustrated in the form of mathematicalmodels in Figure 2. Each polynomial curverepresents the anticipated mortality rateaccording to our hypothesis, where thetrees have ≤ 40%, ≤ 30%, ≤ 20% and≤ 10% of critical residual crown (%CRC).

The curves show the relationship betweenthe percentage of maple trees likely todie (M%) and the average percentage ofcanopy lost in the stand (%Cl= 100% - % ofresidual canopy).

Two years after the ice storm, it is clearthat the severely damaged maple treesare in a stable although critical condition.The mortality scenarios based on the≤ 40% and ≤ 30% critical residual crownthresholds are applicable mainly to standson sites that are less suitable for sugarmaples, such as steep slopes and mountaintops. On such sites the harmful effects ofthe ice storm will be felt in the mediumand longer terms. However, the mortalitysimulations based on the ≤ 20% and≤ 10% critical residual crown thresholdspaint a realistic picture of the anticipatedshort-term effects in well-situated sugar-bushes. Indeed, the actual mortality ratesrecorded in 1999 are not significantlydifferent from those produced by the≤ 10% CRC model (Figure 2).

19C H A P T E R 1


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Table 3, constructed from the results ofFigure 2, establishes a relationship betweenthe anticipated mortality rate and the levelof damage suffered by a stand.

Generally speaking, significant salvagework will be required in heavily damagedtolerant hardwood stands (61% to 80%of crown loss), where 45% to 57% ofthe trees are likely to deteriorate or diein the coming years. In severely damagedsugarbushes where the trees lost ≥ 80%of their branches, between 77% and 94% ofthe trees are actually at risk. In moderatelydamaged stands, however, only 22% to 28%of the trees have deteriorated, and thefigure drops to ≤ 10% in lightly damagedstands.

In addition, it should be rememberedthat the damage suffered by 64% of theforests affected by the 1998 ice stormvaried from “slight” to “moderate” (6).As we will see later (section 2.3), salvage ofwood at risk is not profitable in slightlyor moderately damaged stands, especiallywhen they contain a high percentage ofpulpwood, and forest advisors should informproducers of this fact before any work isundertaken.

In light of the data currently available,it is still difficult to determine how treesthat were severely damaged in January1998 will react in the next few years.

Moderate

FIGURE 2 MORTALITY RATES OF MAPLE TREES, ESTIMATED ON THE BASISOF FOUR CRITICAL RESIDUAL CROWN THRESHOLDS (%CRC98)AND THE AVERAGE PERCENTAGE OF CANOPY LOSS IN THE STAND

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20C H A P T E R 1


Crown-damaged trees, especially sugarmaples, are recovering slowly, and willneed many years to rebuild completely.The data that will be collected in thenext five years will be used to validatethe preliminary results shown in Table 3.However, visual vitality indicators can beused in the short term to distinguish deadand dying trees from trees that have achance of surviving in the longer term.Forest advisors responsible for assessingdamage and selecting trees for salvage canbase their calculations on the Table 4 data,especially when marking trees for priorityharvesting.

Average %of canopy

lost in the stand

≤ 20%

21% - 40%

41% - 60%

TABLE 3 MORTALITY RATE OF MAPLE TREES BY LEVEL OF DAMAGE IN 19981

SEVERITY OF DAMAGE MORTALITY RATE OF MAPLE TREES

CRITICAL RESIDUAL CROWN

QUALITY OF SITECATEGORY

SLIGHT

LIGHT

MODERATE

HEAVY

SEVERE

1 Most likely mortality rate in sugarbushes in the short (2 years)** and medium (5 years)* terms, and probably in othertolerant hardwood stands too.

≤ 40% ≤ 30% ≤ 20%* ≤ 10%**

Poor > > Good

61% - 80%

> 80%

4% 3% 1% 1%

19% 15% 10% 7%

41% 36% 28% 22%

69% 64% 57% 45%

100% 100% 94% 77%

Severely damaged maple trees that survived the 1983 icestorm have produced epicormic sprouts and adventitiousbranches, especially at the base of the crown. When marking,these indicators of vitality can be used to distinguish betweentrees to be harvested and those to be left standing.

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21C H A P T E R 1


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- Uprooted or icefallentrees

- Severely leaning trees(> 40o)

- Trees wounded on twofaces of the bole andconsidered vulnerableto decay, including redmaples and beech

- Trees broken below thecrown

- Trees damaged by can-ker and decay fungus

- Softwoods with crowndamage at a levelwhere the diameter is≥ 6 cm

- Dying trees that havelost part of their bark

No recovery in the crown

Very slow (> 8 years)

Sometimes numerousstump sprouts

Weak

High risk

High risk

< 5 years

Yes

Yes

Short-term

Medium-term(maple sugar production)

Less than 20% of residual crown(< 60% for aspen)

Dying Trees Viable Trees

- Slightly leaning trees(angle of 30o to 40o)

- Trees wounded on oneface of the bole

- Sugar maples less than40 years old, growingon good sites

- Species known to beresistant to crown loss,such as the basswood,ash, oak, black cherry,etc.

- Mature white and redpine trees with severecrown loss

Presence of adventitioussprouts and epicormictwigs in the crown or onthe bole

Slow (5 to 8 years)

Presence of stump sprouts

Variable depending onthe quality of the site

Moderate to low risk

Moderate to low risk

> 5 years

Variable depending onthe quality of the site

No

Variable

Variable

All trees that are not deador weak are consideredto be vigorous or qualitytrees

Significant recovery in thecrown or on the bole

Normal (< 5 years)

Few stump sprouts

Strong

No risk

No risk

> 15 years

No

No

Long-term

TABLE 4 VISIBLE INDICATORS OF VITALITY AND PROBABLE RECOVERYIN ICE-DAMAGED TREES

DEAD TREES WEAK TREES LIVING TREES

Description:

No crown

Visible vitality:No recovery inthe crown

Healingof taps: NilCompanionspecies:No stump sprouts

Probability ofrecovery: Nil

Root rot: High risk

Timber down-grading: High riskLife expectancy:None

Wood at risk: Yes

Timber to be harv-ested in priority: Yes

Salvage period:Short-term

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23C H A P T E R 2

they serve as a pretext for convertingstands with timber or maple potential intoagricultural land, even if they are low indensity and poor in quality, or contain lessvaluable species such as grey birch or redmaple from stump sprouts. The Act toprotect agricultural land and agriculturalactivities6 contains certain provisionsconcerning sugarbushes. The Commissionde protection du territoire agricole hasbeen required, since 1978, to preservesugarbushes in order to maintain mapleproduction activities for the benefit offuture generations. In particular, the Actstates that “No person may, except withthe authorization of the Commission, usea sugarbush situated in a designatedagricultural region for any other purpose,nor fell maple trees there, except for thepurpose of selection or thinning withinthe framework of forest management”(1978, c. 10, s. 27).

Producers, assisted by forest advisors,must do all they can to restore damagedstands, to preserve biological diversity, andto ensure adequate regeneration of standsin which salvage work is required.

The silvicultural work proposed in thisdocument has been adopted to avoidcompromising stand health. Excessivethinning of the canopy can reduce thevigour of residual trees and affect maplesap production, causing tree quality todecline and altering the stand’s naturaldevelopment. A more plentiful supply oflight may promote the growth of intolerantspecies that will compete with sugar mapleseedlings and other high-value hardwoods.The quality trees will also be vulnerable tosunscald, the ratio crown/bole may become

MANAGEMENT OF DAMAGED FOREST STANDS

2.1 THE OBJECTIVES OFTREATMENTS INDAMAGED FORESTS

Silvicultural work in damaged forests isaimed at:

• salvaging wood at risk, especially,lumber;

• promoting the recovery of stands thathave maintained a certain potential fortimber or maple sugar production;

• restoring to production any sitesdamaged too severely to producequality hardwoods or softwoods;

• preserving soil quality (physical andchemical properties) in stands that havebeen destroyed or severely damaged;

• protecting the maple production heri-tage;

• preserving exceptional forest ecosys-tems, certain specific wildlife habitatsand vulnerable animal and plantspecies.

Salvage operations should be carried outfirst in severely damaged hardwood standscontaining lumber at risk (see sections 2.3.1,2.3.2 and 2.3.3). Saw logs and veneer logsare likely to lose their value more quicklythan pulpwood (4) (5). They also have ahigh economic value and are easier to sellthan pulpwood.

The first stands to be salvaged shouldbe those containing crop trees likely toproduce lumber or substantial quantities ofmaple sap. However, salvage operationsshould not compromise the stability ofresidual stands or endanger any rarespecies that may be present, nor should

6 Act to protect agricultural land and agricultural activities, (R.S.Q., c. P-41.1), amended on April 1, 1998.

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24C H A P T E R 2

M A N A G E M E N T O F D A M A G E D F O R E S T S T A N D S

greater or they may be attacked by thesugar-maple borer, Glycobius speciosus (Say),and bole or root rot fungi including Cerrenaunicolor (Bull.:Fr) Murr. and Armillariaostoyæ (Romag.) Herink (6) (9). If theresidual density falls below a certain criticalthreshold, the trees are weakened and bothstand stability and soil quality are compro-mised (11). It is therefore important tocomply with the recommended densitythresholds for each stand. The densitythresholds, expressed as the basal area oftrees with a dbh of ≥ 9.1 cm, are the bestindicators at our disposal for estimatingprobable stand recovery (see the summarytables in section 2.3).

There are fewer restrictions on salvageand management work in high-densitystands that have suffered only moderatedamage. However, there is much lessflexibility in severely damaged stands witha low initial density, since only dead treescan be salvaged over short rotations (from3 to 5 years). Excessive logging may wellcause more harm to the stand than theice storm. Indeed, it is often best to leavethe poor quality trees standing, since theywill help restore the stand. If they are cutindiscriminately, tree vigour may be reduced,

stand structure may be altered, and standsurvival may actually be threatened, espe-cially for sugarbushes.

2.2 SALVAGE PRIORITIES

The process of salvaging ice-damagedtrees must be planned very carefully, inparticular to avoid wasting the resource andplacing additional stress on the survivingtrees, thus compromising maple sap orlumber production in sugarbushes andother stands. Salvage priority is establishedaccording to the risk of downgradingthe various species, the amount of debrishindering access to the forest, the qualityand value of the trees to be salvaged, andmarketing considerations.

In general, it is best to salvage sawinglogs (priority 7) before icefallen or severelyleaning pulp quality trees (priority 8).However, on some sites this priority orderwill need to be reversed, so that machinerycan circulate freely in the forest. Even so,before salvaging weak trees for pulpwood(priorities 6, 7 and 10 in Table 5), forestersshould always ensure that the wood can

Young, severely damaged sugarbush invaded by strong trembling aspensaplings that are likely to alter the stand’s composition if logging isexcessive.

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During salvage operations, special care must be taken to protect wildlifehabitats, exceptional forest ecosystems and rare or vulnerable animaland plant species such as Galearis spectabilis.

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25C H A P T E R 2


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be sold on markets that might wellbecome saturated, at least temporarily, inthe coming years. Otherwise, the resourcemay be wasted. Table 5, which presents apriority order for salvage operations, canbe used as a guide during marking.

It is important to remember that theorder proposed in the table will varydepending on the production objectives andthe situation of the woodlot owner. Forestadvisors should remember, among otherthings, that maple producers may decideto sacrifice a certain amount of maplelumber in order to preserve as many tapsas possible. Such a choice is perfectly jus-tified from a maple production standpoint(see section 2.3.3.1). Marking will thereforediffer from one sugarbush to the next,depending on the type of production re-quired. However, post-salvage stand densitymust always be sufficient to preserve vigourand allow for regeneration by desirablespecies.

Dead yellow birch and white birchtrees lose their value quickly, becausethe sapwood changes colour when humiditylevels drop (4). They should therefore besalvaged first, and processed immediately.Sugar maples and companion species,however, maintain their value for a muchlonger period, and salvage operations canwait at least a year. In the case of weakhardwoods that have retained 20% or lessof their crowns, saw quality trees withsignificant wounds to the bole or base ofthe crown should be salvaged first, beforethey are attacked by discoloration fungi.It should be remembered that only fungalsap-stain is a threat in the short term,and that heartwood defects (brown-stainor decay) are not due to the 1998 icestorm. In addition, the large number ofbranches developing at the base of seve-rely damaged yellow birch crowns willeventually be detrimental to veneer quality.

Generally speaking, trees that wereweakened can be left standing as long astheir cambium is still alive and humiditylevels remain high. They should be rankedfor salvage based on their species, age,residual crown and wounds. Young treesare more vigorous and resistant than oldertrees, and companion species such as whiteash, red oak, butternut, bitternut hickory,black cherry and American basswood havea better chance of survival than the sugarmaple, even if they are severely damaged.

Indeed, it should be remembered thatthe species most vulnerable to icedamage are also those that are bestable to rebuild their crowns. However, theaspens and birches are more susceptibleto sap-stain and decay fungi than theother hardwoods. Weak aspens are alsoundesirable as seed trees, especially in

Veneer quality yellow birch that suffered severe crown lossas a result of the 1983 ice storm, and whose value hasbeen adversely affected by the adventitious branchesdeveloping on the bole.

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26C H A P T E R 2


sugarbushes, and they should therefore beharvested first. Crown-damaged conifersincluding fir, spruce, larch, jack pine, hem-lock and cedar, are much more susceptibleto attacks by the pine sawyer and decayfungi than large white pine and red pinetrees (see Appendix 4). These latter, evenwhen they have lost some of their branchesor part of their crowns, continue to be goodseed trees and should be preserved indamaged natural forests. Ice damage shouldtherefore not be used as an excuse to cutdown pine trees that have not reachedmaturity, except in very severely damagedplantations where surviving trees areinsufficient in number and thus susceptibleto windthrow (see section 2.3.5.4).

Icefallen or severely leaning trees arelikely to die or deteriorate in the mediumterm, even if their crowns are intact. Youngbirch trees are especially vulnerable.However, trees of other species will survivein good condition for several years, becausetheir crowns are generally not in contactwith the ground and they create shade,preventing the ground from drying out andprotecting the seedlings from sunscald.Since they are rarely large enough forlumber production, they can be salvagedlater as pulpwood or fuelwood.

2.3 SILVICULTURAL WORK INDAMAGED STANDS

The summary tables and logic diagramsin this section show the different silviculturaltreatments and variants for hardwood,mixed and softwood merchantable (even-aged plantations and natural stands) ornon-merchantable (uneven-aged stands)stands, and for young pre-merchantablestands. In merchantable stands, specificdensity thresholds should be applied, so as:

• to preserve the vigour and quality ofthe residual trees;

• to ensure the stand’s ecologicalstability;

• to avoid leaching of certain chemicalelements from the soil;

• to reduce the risk of windthrow;

• to stimulate regeneration of desiredspecies, thus promoting the restorationof production to the site;

• to ensure sustainable development.

TABLE 5 SALVAGE PRIORITY ORDER IN ICE-DAMAGED STANDS

1. Dead saw quality yellow or white birch trees, whether standing or uprooted.

2. Dead saw quality trees of other species, whether standing or uprooted.

3. Dead pulp quality trees, whether standing or uprooted.

4. Weak saw quality yellow or white birch trees.

5. Weak saw quality aspens.

6. Weak pulp quality aspens.

7. Weak saw quality trees of other species.

8. Living pulp quality icefallen or severely leaning trees (see Appendix 2).

9. Defective pulp quality softwoods.

10. Weak pulp quality hardwoods other than yellow birch trees.

27C H A P T E R 2


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In sugarbushes, companion species such as the butternutrecover better than the sugar maple and help maintainthe biodiversity and stability of the stand.

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DID YOU KNOW?

In sugarbushes, salvage work should ideallybe carried out in the winter, to protectadvance growth and tree roots. Heavymachinery should not circulate in the forestduring the fall rainy season or in early spring,to avoid rutting. Advance-growth shouldalso be protected by spacing out machinerytracks (see also sections 2.3.2 and 2.3.4for red maple and mixed stands).

For example, Figure 3 shows the besttype of harvesting for certain toleranthardwood stands, depending on the basalarea to be preserved. These recommen-dations are explained in detail in sections2.3.1, 2.3.2 and 2.3.3. Section 2.3.4examines mixed stands, and section 2.3.5examines transition hardwood stands,pre-merchantable stands, plantations andconifer forests.

Partial salvage cuttingSanitation cutting

(or sometimes partialsalvage cutting)

Shelterwood cuttingor total salvage cutting

with protectionof advance-growth

Two-step total salvage cutting

Shelterwoodcutting or

total salvagecutting withprotection of

advance-growth

Partial salvage cutting

Sanitationcutting

(or sometimespartialsalvagecutting)

Partial salvage cutting(or sometimes sanitation cutting)

FIGURE 3 HARVESTING METHODS RECOMMENDED BY BASAL AREA TO BEPRESERVED IN TOLERANT HARDWOOD STANDS

TYPE OF BASAL AREA TO BE PRESERVED STAND 12 m2/ha 14 m2/ha 16 m2/ha 20 m2/ha 22 m2/ha

TOLERANTHARDWOODS

MANAGEDFOR LUMBERPRODUCTION

RED MAPLES

MAPLE STANDSMANAGEDFOR SAP

PRODUCTION

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2.3.1 Tolerant hardwood stands(other than red maple)

Instructions concerning the best silvicul-tural treatments for each type of toleranthardwood stand are summarized in thefollowing pages, in the form of easy-to-consult synoptic tables. Figure 4, forexample, indicates the best harvestingmethods according to the basal area tobe preserved7 in tolerant hardwood stands(other than red maple) managed for lumberproduction. Sanitation cutting is recom-mended in lightly or moderately damagedstands, and shelterwood cutting or totalsalvage cutting with protection of advance-growth is recommended in stands destroyedby the ice storm. The future of stands inwhich the basal area of living trees variesfrom 14 m2/ha to 20 m2/ha is uncertain;some of the dead or dying trees should besalvaged first, and the development of thesurviving trees should then be monitoredfor a period of five years before makinga final decision. The recommendations inFigure 4 also apply to other types of hard-wood stands, although the basal arearequirements for living trees differ (seeFigure 3 and sections 2.3.2 and 2.3.3).

7 The recommended basal area thresholds are more conservative than those proposed by American authors who believethat hardwoods not damaged by ice can self-prune properly after partial cutting when the residual density varies from16 m2/ha to 18 m2/ha.

FIGURE 4 DECISION KEY FOR MANAGING MERCHANTABLETOLERANT HARDWOOD STANDS

Shelterwoodcutting or totalsalvage cuttingwith protection

of advance-growth

Sanitation cutting

Leave more than20 m2 / ha

Partial salvage

Initially, salvage only the deadand weaker trees, then monitor

the situation for 5 years.

BASAL AREA

TO BE PRESERVED

> 20 m2 / ha

from 14 m2 / ha to 20 m2 / ha

< 14 m2 / ha

Sugarbush heavily damaged in 1998 where total salvagecutting with advance-growth protection is required.

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No intervention required

• Review marking if selection cuttingor thinning is planned

Sanitation cutting

• Leave ≥ 20 m2/ha

• Salvage < 20% of the initial basal area

• These stands should retain theirtimber production potential

• The maple production potential ofyoung stands will remain at an accept-able level if ≥ 150 taps per hectarecan be installed (see section 2.3.3.1)8.

Partial salvage cutting9

• Salvage only dead trees and weakersaw-timber quality trees

• These stands face an uncertainfuture, depending on the quality ofthe site, the vigour of the trees, theirage, and so on

• Take follow-up action after 3 years tocheck the amount of advance-growthand the condition of the residual trees

Total salvage cutting with protection ofadvance-growth

Shelterwood cutting9

• Recover deteriorating saw-timber qual-ity trees first

• Assess advance-growth density

• Wait at least 5 years before salvagingthe residual stand

• Consult section 2.3.3.2 to select thebest restoration method

• Protect soil and advance-growth duringlogging operations

• ≥ 80% of crown intact

• Not enough trees for salvage to justifyharvesting

• Medium to high density stands wherethe trees have retained 40% to 80%of their crowns

• Not enough trees for salvage to makeharvesting profitable (less than20 m3/ha) (see Table 3)

• Living trees ≥ 20 m2/ha

• Enough vigourous or quality trees(200-400/ha) based on the site’squality

• Medium to high density stands wherethe trees have retained 40% or less oftheir crowns

• Dead or weak trees represent ≥ 30%of the initial basal area

• Dead or weak trees generally represent> 20 m3/ha, except in low densitystands

• Living trees represent between14 m2 and 20 m2/ha

• Stands in which extensive salvage workis required

• Stands where the trees have retainedless than 20% of their crowns

• Living trees represent less than14 m2/ha, except in young stands

• The surviving trees will produce poorquality timber, and the stand must beregenerated

SEVERITY OFDESCRIPTION

RECOMMENDED SILVICULTURALDAMAGE TREATMENTS

SLIGHT

LIGHTOR

MODERATE

HEAVY

SEVERE

8 If young hardwoods such as the yellow birch have been downed or are severely leaning, they should be returned to anupright position and then staked or supported (especially if they are growing in bare patches created by the removal ofolder trees), otherwise they will die. Saplings leaning at an angle of less than 45o should recover on their own in thecoming years. Young beech trees, especially those grown from root suckers, should be cut to leave more room for othercompanion species (see section 2.3.5.2).

9 Partial salvage, total salvage or shelterwood cutting may be carried out in patches of heterogeneous stands where verysevere damage is limited.

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10 If young red maples have been downed or are severely leaning, they should be cut back, especially if they are growing inbare patches created by the removal of older trees, otherwise they will die. Saplings leaning at an angle of less than45o should recover on their own over time (see also section 2.3.5.2).


Sanitation cutting, if necessary

• Review marking if selection cutting isplanned



• Recover only dead trees and weakersaw-timber quality trees

• These stands should retain theirproduction capacity if the site is ofgood quality10

• Take follow-up action after 3 years tocheck the condition of the residualtrees

Two-step total salvage cutting11

• Salvage deteriorating saw-timberquality trees first

• Wait at least 5 years before salvagingthe residual volume, which will beused mainly for pulp and fuel purposes

• Protect soil and advance-growthduring salvage operations

• Regeneration will come partly fromstump sprouts

• Medium to high density stands wherethe trees have retained 40% or less oftheir crowns

• Dead or weak trees represent ≤ 30%of the basal area

• Not enough trees (less than 20 m3/ha)for salvage to make harvesting profit-able


• Dead or weak trees represent ≥ 30%of the basal area

• Dead or weak trees generally represent≥ 20 m3/ha, except in low densitystands

• Trees that have retained more than20% of their crowns represent morethan 16 m2/ha

• There are enough vigorous or qualitytrees (200-400 trees/ha) based on thequality of the site

• Stand is severely damaged and veryextensive salvage work is required

• Stands where the trees have retained> 20% of their crowns represent< 16 m2/ha

• It is unlikely that the stand will producequality trees upon maturity, and itneeds to be regenerated

• Red maple trees are very susceptibleto decay and will deteriorate, unlessthey are under 25 years old

2.3.2 Red maple stands

The silvicultural treatments recommended for red maple stands are also suitable fortransition stands containing varying numbers of intolerant hardwoods such as aspens orwhite birch, and for stands containing a significant percentage of fir and yellow birch.



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No intervention required

• See the management method thatwill produce optimal yields in thesestands (section 2.3.3.1)

Sanitation cutting


• Salvage < 20% of the initial basalarea

• These stands should retain their sapproduction potential

See the management method that willproduce optimal yields in these stands(sections 2.3.3.1 and 2.4.1).


• Salvage only dead trees12

• The future profitability of sap productiondepends on the quality of the site, thevigour of the trees and the density ofthe residual stand (see section 2.4.1)

• Review the stand’s sap productionpotential in 3 years’ time (see sections2.3.3.1 and 2.4.1)

Shelterwood cutting13

• It is unlikely that such a stand will beprofitable in the short term

• Assess advance-growth density

• Consult section 2.3.3.2 to select thebest restoration method

• See also section 2.4.1 on tappingmethods

• ≥ 80% of residual crown

• Not enough trees for salvage to justifyharvesting


• Not enough trees have been destroyedor are threatened to make harvestingprofitable in the short term (see Table 3)

• Living trees represent ≥ 22 m2/ha

• Medium to high density stands wherethe trees have generally retainedbetween 20% and 40% of their crowns

• Dead or weak trees represent ≥ 30%of the basal area

• There are some trees for salvage, butthe quality and quantity of lumbervaries by age and condition

• Living trees represent between12 m2/ha and 22 m2/ha

• Stands in which extensive salvage workis required

• Stands where the trees have retainedless than 20% of their crowns

• Living trees represent less than12 m2/ha, except in young stands

• The surviving trees will produce poorquality timber, and little sap.



SLIGHT

LIGHTOR

MODERATE

HEAVY

SEVERE

12 If young sugar maples have been downed or are severely leaning, they should be returned to an upright position and thenstaked or supported (especially if they are growing in bare patches created by the removal of older trees), otherwise theywill die. Sugar maple saplings leaning at an angle of less than 45o should recover on their own in the coming years. Youngbeech trees, especially those grown from root suckers, should be cut to leave more room for other companion species(see section 2.3.5.2).


2.3.3 Maple stands managed for sap production

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2.3.3.1 Sugarbush management method

To understand the recommended methodof restoring damaged sugarbushes, it isuseful to have a basic grasp of the man-agement methods generally used in healthystands. In both cases, there are two maingoals, namely to optimize maple sapproduction and to obtain an acceptablereturn on the money invested. To achievethis, it is necessary:

1. before intervening, to ensure that thebasal area is at least 24 m2/ha, other-wise thinning is not possible;

2. to preserve at least 180 taps/ha whenthinning. However, young sugarbushesare considered to have potential if theyallow for at least 150 taps/ha;

3. if there are signs of dieback, if light-tolerant species are present or if thereis a shortage of young maple saplings,to preserve a minimum basal area of20 m2/ha when thinning;

4. to carry out thinning every 10 or 15 years,and to remove ≤ 20% of the basal area,including trees that are accidentallywounded or cut down on the haulingtrails;

5. to preserve 10% to 15% of co-dominantcompanion species, ensuring that theyare evenly distributed throughout thesugarbush;

6. to maintain a balanced uneven-agedstructure throughout the sugarbush,thus promoting renewal (11) (14);

7. to improve the stand’s productivity bygradually eliminating weak, defective andpoorer quality trees, to leave more roomfor previously crowded crop trees (11);

8. when marking, to pay special attention to:

• undesirable species;

• weak or defective trees, i.e. trees invigour classes 3 and 4 (see Tables 1and 2).

DID YOU KNOW?

The companion species to be retained aremostly tolerant to shade, and include theeastern hemlock, white spruce, ironwood,red oak, American basswood and white ash.Trees of certain semi-tolerant or intolerantspecies should also be preserved, includingthe white pine, yellow birch, bitternut hickory,butternut, American elm, hackberry, greenash, bur oak, white oak and black cherry.The climax and semi-climax species describedgrow naturally in stands that have reachedthe last successional stages. They do notthreaten the stability of sugarbushes(see also Appendix 4).

Sugarbush destroyed by the 1983 ice storm in theLanaudière region now replaced by the vigourous younghardwoods that were protected during salvage cutting.

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Maple producers should follow markingrules established according to their prioritygoals14, by marking, in order:

1. Undesirable species, such as balsamfir trees15, which are cut down to ensurethe sustainability of the sugarbush andprevent it from deteriorating or evolvinginto another type of stand in the longerterm (15 years)16.

2. Weak, defective or diseased trees, whichare cut down to eliminate specimens withcanker or advanced decay, and especiallythose whose branches are likely to bebroken off by the wind, to guarantee thesafety of human beings and property, andto prevent the spread of diseases suchas eutypella canker, Eutypella parasiticaDavid. & Lorenz.

3. Invasive companion species such as thebeech, which are partially harvested inorder to release young quality maplesgrowing close-by in overcrowded condi-tions. However, beech trees should notbe eliminated systematically, since thiswould open up the stand too much,stimulating a suckering response andthus threatening the stability of thesugarbush.

14 These rules obviously apply only if the sugarbush was not heavily damaged by the ice storm. Otherwise, the priority ordershown in Table 5 should be applied.

15 Eliminating balsam fir trees also reduces the risk of squirrel damage to tubing.16 Normal life span of tubing used for collecting sap.

DID YOU KNOW?

In a sugarbush, undesirable species includethe balsam fir and transition species such asthe trembling aspen and white birch, whichthreaten the stability of the stand. Beechpropagation should also be limited, andthis species should not account for morethan 20% of the basal area (15).

4. Overmature maples, which are cutdown in order to eliminate trees thatgrow too slowly and yield only smallquantities of sap, so as to maintainmaple production levels in the longerterm. The selection process benefitsnearby vigorous and quality trees withgood radial growth.

5. Lastly, if the above goals are achieved,old, still vigorous trees are then markedto maintain or restore a balanced uneven-aged structure in the sugarbush, thuspromoting renewal.

It is important to remember that it isdifficult if not impossible to achieve allthese goals in a single thinning operation,since it is necessary to harvest ≤ 20%of the initial basal area and preserve aresidual density of ≥ 20 m2/ha. Sugarbushimprovement is a long-term process thatmust be carried out in successive steps.Extensive thinning may well modify thestructure of the stand, provoke windthrow,expose the trees to insects and diseasessuch as dieback, and kill young sugarmaples. The selection of the trees to beharvested will vary from one sugarbushto the next, according to the structure,composition and density of the stand andthe health of the individual trees. Harvestingof overmature or diseased trees consideredsurplus to requirements in the variousdiameter categories promotes the growthof crop trees and thus creates openingsconducive to regeneration. By makingwell-calculated, balanced treatments,maple producers can gradually restoretheir sugarbushes and achieve optimal,sustainable yields.

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2.3.3.2 Restoration of sugarbushes destroyedby the ice storm

Heavily damaged sugarbushes with abasal area of less than 12 m2/ha of survivingtrees are likely to disappear completely ordeteriorate to such an extent that they arenot worth preserving. Stands such as theseare considered to have been destroyed.In such cases, silvicultural treatments shouldbe aimed at renewing the stand in theimmediate future, or at least avoidingfurther deterioration of the site.

Total salvage cutting with advance-growthprotection is the best method for sugar-bushes in which sugar maple and high-value hardwood saplings are present insufficient numbers and evenly distributedthroughout the ice-damaged area. However,this approach is not appropriate and shouldbe avoided if there are not enough sugarmaple saplings. In this latter case, shelter-wood cutting is recommended.

Total salvage cutting with advance-growthprotection is designed to promote theestablishment of a new stand equal orsuperior in quality to the damaged one.The canopy is partially opened to stimulatethe growth of maple seedlings and saplingsand the establishment of high-value hard-woods such as the American basswood,yellow birch, American ash, red oak andthe hickories, which need a plentiful supplyof light to become established and growquickly in the early stages (see Appendix 4).

Harvesting methods are more or lessthe same in all tolerant hardwood stands.They depend on the abundance and typeof advance-growth, which in turn indicatesthe stand’s level of stability. The methodswill differ according to whether the goal is:

• to restore a sugarbush that was des-troyed and is not regenerating well;

• to restore a sugarbush that was des-troyed but is recovering;

• to restore a sugarbush that was des-troyed and has regenerated in speciesother than the sugar maple.

Sugarbushes destroyed by the ice stormand not regenerating well

Regeneration is said to be insufficient ifthere are fewer than 5,000 viable sugarmaple seedlings per hectare in a sugar-bush. A sugar maple seedling is viable if itis ≥ 0.5 m high. Smaller seedlings thatare suddenly exposed to the sun are likelyto die in the coming years due to droughtor attacks by the pitted ambrosia beetle,Corthylus punctatissimus Zimm. They shouldtherefore be ignored in the regenerationsurvey, as should seedlings and saplingsof undesirable species, such as balsam firAmerican beech or red maple. In addition,transition species such as the aspensshould not be counted, since they alsothreaten the stand’s succession and normaldevelopment.

Maple stands that do not contain enoughsugar maple saplings may not renew ade-quately, especially if they are dense and stillgrowing and if they are used as browsingareas for cattle. A similar problem may alsobe encountered in cleared stands used forsap production.

Initially, partial salvage cutting shouldbe carried out to harvest the deterioratinglumber, beginning with the quality trees inaccordance with the priority order proposedin Table 5 (see section 2.2). Partial openingof the canopy will stimulate the regenera-tion of desirable species while ensuring thatmaple seedlings receive minimum compe-tition from intolerant species and properprotection from drought and sunscald.

Ideally, a total of 50 seed trees perhectare should be left, including companionspecies. Forest advisors may sometimessuggest a lower figure, especially in standsgrowing on shallow soil cover on sites

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exposed to the wind, since adult trees arelikely to fall, die back or deteriorate tosuch an extent that they will no longer beworth salvaging in the final harvest.

The stability of stands growing on shallowor poorly drained soil is at risk in the shortterm. If regeneration is insufficient afterthree years – a situation that is likely tooccur on the sites least favourable to thesugar maple – it should be filled in withother high-value hardwoods and white pinetrees (10 and 21). The final cut will takeplace no earlier than five years after theinitial treatment, when the new growth hashad time to become established. Measuresmust be taken to protect the future standduring harvesting.

Sugarbushes destroyed by the ice stormand in the process of growing back

Stands containing enough sugar maplesaplings, i.e. at least 5,000 viable ones perhectare, including 400 evenly-distributedcrop trees, have a good chance of recovery.In stands under reconstruction, new growthwill often have become established follow-ing dieback, logging or other disturbancesprior to the ice storm. The normal succes-sion and stability of such stands is not at

risk, and one-step total salvage cuts cantherefore be carried out provided theadvance-growth is protected. To protectyoung maple trees, it is best to carry outsalvage operations at the beginning ofwinter, cutting trees at an angle of 20o

to 30o from the hauling trails, whichshould be between 20 m and 30 mapart. If possible, the branches shouldbe removed on the logging site priorto hauling.

Destruction of the forest canopy by theice will stimulate the growth of youngtrees in the coming years. Crop trees musttherefore be released as soon as they areidentified, i.e. when they exceed the regen-erating storey, or in approximately 10 years’time. Screening for young vigorous mapletrees is usually carried out during thesummer, and the final choice of crop treesis made the following spring based onthe sap sugar content, measured using a

Poor practices, such as cattle browsing and brush clearing, have graduallyaltered the composition and age structure of many sugarbushes to suchan extent that after a bad ice storm they no longer contain enough croptrees to replace severely damaged dominant specimens.

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Sugarbush severely damaged by the 1983 ice storm, butnow under reconstruction.

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refractometer (15). Crop trees should bebetween 3.5 m and 5.0 m apart, with aclear area of 75 cm around the crown.This allows for between 400 and 800 treesper hectare. Crop trees are selected fromsaplings with a larger-than-average diam-eter and height, since the others have littlechance of becoming dominant in the newstand (22) (see section 2.3.5.2).

Sugarbushes destroyed by the ice stormand regenerating with species other thanthe sugar maple

Destroyed stands that are regeneratingwell, but in species other than the sugarmaple, pose the most problems. The timeneeded for them to resume maple sapproduction will vary according to thequality of the site. New growth on rapidlydrained sites at the top of slopes and poorlydrained sites in depressions is usually com-posed of American beech, red maple andintolerant hardwoods. Dry sites are ofteninvaded by raspberry plants, including Rubusidaeus L., while subhydrous sites attractferns such as Matteuccia struthiopteris (L.)Tod. Sugar maple trees that survive onthese sites will very probably decline anddie in the next few years (see section 1.2,

Figure 2 and Table 3). Such stands do nothave sufficient potential for sap production,and the timber should be salvaged.

A one-step total salvage cut can becarried out, but it is best to leave between10 and 20 seed trees per hectare, prefer-ably companion species, even if they areeventually lost to windthrow. This measureis suitable only for sugarbushes in whichthe maple trees have been, or are beingreplaced by other species. On dry siteswith shallow soil cover, stands should berestocked with red oak and white pineseedlings, and on wet sites, with bur oakand yellow birch.

Sugarbush approximately 15 years old that underwent pre-commercialthinning in 1998 (See last photo on previous page).

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DID YOU KNOW?

A regenerating tolerant hardwood forestusually has more than 12,000 seedlingsper hectare, or 30 saplings per 25 m2

sub-plot. In sugarbushes, there should beat least 5,000 viable sugar maple seedlings(i.e. over 0.5 m high) per hectare, includingat least 400 well-spaced crop trees, espe-cially where the ground has been cleared.If new growth is insufficient or poorly dis-tributed, the canopy should be openedgradually to prevent the site from beinginvaded by trembling aspen, white birchand raspberry, which would endanger theoriginal stand’s ecological stability.

DID YOU KNOW?

Winter logging can limit the spread of intol-erant hardwoods while protecting mapleand other high-value hardwood seedlings.However, if the goal is to maintain orincrease the number of yellow birch treesin a stand, it is best to begin logging in thefall, disturbing the soil sufficiently to createa proper seedbed for the birch seedlings,whose rootlets cannot penetrate a thicklitter.

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2.3.4 Mixed stands

In mixed stands, hardwood trees such asthe yellow birch and trembling aspen havegenerally suffered more severe damagethan the conifers. Balsam fir trees, sprucetrees, jack pines, larches, hemlocks andcedars (FSPLHC) that have been uprootedor have suffered crown damage at a diam-eter in excess of 6 cm must be salvagedwithin three years, to avoid deteriorationby red heart rot17. The same applies toweak hardwoods with severe bole woundsthat have retained 20% or less of theircrowns (or less than 60% in the case ofweak aspens) (see section 1.1, Table 2).The damage can first be assessed sum-marily, and then, if necessary, the mixedstand can be surveyed and a salvage plandrawn up. Partial salvage cutting is justi-fied if the weak hardwoods, aspens andsoftwoods (FSPLHC) account for ≥ 30%of the stand basal area. For managementpurposes, mixed stands should be subdividedinto two categories:1. those containing tolerant or semi-tolerant

hardwoods;2. those containing intolerant hardwoods.

Mixed stands with tolerant or semi-toleranthardwoods, such as the yellow birch, sugarmaple and red maple:

salvage the weak or defective trees,leaving at least 10 vigorous hardwoodsper hectare (yellow birch or sugar maple)selected from the dominant or codomi-nant storeys18, to serve as seed trees.

Mixed stands with intolerant hardwoods,such as the trembling aspen and whitebirch:

1. if advance-growth of desirable speciesis insufficient, carry out a partialsalvage cut, preserving only thesoftwoods and commercial hard-woods whose quality is not at risk;

2. if advance-growth of desirable speciesis sufficient and well-establishedin the stand, carry out a partialsalvage cut to eliminate the weakor defective trees19, beginning withintolerant species. No more than40% of the basal area should beharvested, to prevent windthrow.

17 Red and white pine trees, which often grow alongside hardwoods, are not included in the FSPLHC group. Pine trees thathave lost their crowns or some of their branches do not need to be salvaged urgently, because their boles are not likelyto deteriorate in the medium term.

18 Although it is difficult to predict how mixed stands with tolerant hardwoods will regenerate, there is some concern thatradical opening may trigger an invasion of raspberries, intolerant hardwoods and softwoods, including balsam fir. Forestmanagers should therefore promote the establishment of yellow birch, at the expense of softwood and intoleranthardwood species. To do this, the litter should be turned over in small patches during hauling. However, care is neededto avoid scalping the ground and wounding the seed trees during logging. Contrary to prior instructions concerningsugarbushes (see section 2.3.1), trees in mixed stands should be salvaged after they shed their leaves but before theground freezes.

19 A defective softwood whose crown has been broken off at a diameter of 6 cm or more should be salvaged before thetimber deteriorates (3 years). A weak hardwood that has retained 20% or less of its crown must be salvaged in priority,especially if it is a sawing quality or veneering quality yellow birch (see section 1.2, Table 2).

Sugarbush growing on shallow soil cover where the sugar maples werereplaced by red maples after the 1983 ice storm. Enrichment plantingwith red oak and white pine would have improved productivity.

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2.3.5 Other types of stands

2.3.5.1 Trembling aspen stands

In poplar stands destroyed by the icestorm, the timber can be salvaged in asingle operation. Total salvage cutting isthe best solution if weak aspens make up≥ 50% of the basal area. Growing poplarstands usually regenerate naturally, thanksto root suckering. Older destroyed standsmay be taken over by balsam firs and redmaples previously established in the under-growth. If there are not enough softwoods,the site should be restocked with largeseedlings, and release cutting should becarried out among the young crop trees.

In poplar stands that were less severe-ly damaged, we recommend salvagingsome of the trees with less than 60% ofresidual crown, if they account for 30%of the basal area. Damaged aspens areparticularly vulnerable to white trunk rot

caused by Phellinus tremulæ Bond. & Bor.,white pocket rot caused by Inonotus rheades(Pers.) Bond. & Sing., and hypoxyloncanker, Entoleuca mammata (Wahl.) J.H.Rogers & Ju.

Transition stands containing tolerant hard-woods or softwoods should be managedin accordance with the methods describedin sections 2.3.1, 2.3.2, 2.3.3 and 2.3.4, soas to respect the natural succession order.However, it should be remembered thatcutting will stimulate root suckering inaspens, and is likely to hinder the develop-ment of maple and tolerant hardwoodsaplings. Cutting should therefore takeplace in midsummer, to reduce root suck-ering and, if necessary, to release the croptrees.

2.3.5.2 Pre-merchantable hardwoodplantations and stands

The ice storm also affected some younghardwood stands, causing severely leaningand icefallen trees to become so tangledthat they have no chance of recovery.In such cases, losses are not measured interms of volume, since the trees have not yetreached commercial size and are thereforenot valuable enough to justify harvesting.Forest areas such as these are likely toremain unproductive if nothing is doneto repair them. As we saw earlier, totalsalvage cutting allows young aspen standsto recover by promoting root suckering.However, it is more difficult to restoreyoung transition stands by increasing thepercentage of high-value hardwoods inorder to obtain ≥ 800 crop trees perhectare. Stands that are sufficiently dense(≥ 5,000 trees/ha), i.e. those containing atleast 250 crop trees per hectare, shouldbe restored first. The decision key shownin Figure 5 can be used to establish thebest method of restoring young hardwoodstands. The key is both simple and practical,and takes into account constraints andcosts as well as anticipated benefits.

Trembling aspen bole damaged by white pocket rot,Inonotus rheades (Pers.) Bond. & Sing.

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2.3.5.3 Softwood stands

• Sanitation cuttingThis method is suitable for use in lightly

damaged stands where defective softwoodsaccount for less than 30% of the basalarea. The risk of wounding the trees ishigh if low intensity thinning is carried out,since the forestry workers have less spaceto move their machinery around. Sanitationcutting may therefore be unprofitableand even costly if care is not taken to pro-tect crop trees when cutting and haulingsalvaged trees.

• Total salvage cut with advance-growthprotection

Total salvage cut with advance-growthprotection can be carried out in softwoodstands where fallen trees or trees brokenat a diameter of ≥ 6 cm account for morethan 50% of the basal area, and whereadvance-growth is sufficient and evenlydistributed20. This treatment is not recom-mended in poorly regenerated stands, sinceintolerant species, such as the white birch,striped maple, mountain maple, beakedhazelnut, wild raspberry and fireweedcompete strongly with softwood saplings.

Instead, we recommend partial salvagecutting, which resembles shelterwood cut-ting and is respectful of the renewal andsuccession dynamics of stands followingnatural disturbances.

• Shelterwood cuttingIn damaged, poorly regenerated soft-

wood stands, shelterwood cutting promotesnatural reseeding. It is less costly thanreforestation with large seedlings. Defectiveand diseased trees and those with severecrown damage that are likely to die orfall over while the young seedlings arebecoming established should first be cut.Partial opening of the canopy stimulatesthe germination of desired species whileproviding softwood saplings with adequateprotection from drought and reducingcompetition from intolerant species.

It is preferable to harvest during thewinter if there is a chance that rich, opensites will be invaded by the mountainmaple, or if fir advance-growth is to beprotected. However, if the goal is to obtaina suitable seedbed for spruce and whitepine trees, cutting should take place inthe fall and the litter should be carefullyturned over.

DID YOU KNOW?

The young saplings selected to become croptrees and subsequently released are notnecessarily those that will grow most afterthinning. It may happen that a selected treereacts badly to release cutting and dies or isreplaced by a more vigorous neighbouringtree that does not meet quality standards.As a precaution, we suggest releasing atleast 800 young trees per hectare, oraround one tree every 3.5 m, to obtainnormally stocked stands with the bestpossible distribution coefficient. Pre-merchantable hardwood stand destroyed by the 1998 ice storm.

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20 The aim should be to obtain more than 1,500 saplings, 15-cm high or more per hectare and a distribution coefficient of≥ 60%, i.e. one sapling every 4 m2, in 60% of cases.

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40C H A P T E R 2


FIGURE 5 DECISION KEY FOR MANAGING YOUNG ICE-DAMAGED HARDWOOD STANDS

Average height of

dominant trees

Stand density: ≥ 5,000trees/ha

Top qualitycrop trees≥ 250 / ha

Stand tooyoung to

benefit frompre-commercial

thinning orimprovement

cutting

Average dbhof stand

Refer tomanagement

methodsproposed insection 2.3

Releasethe crop trees

and, ifnecessary,

fill in the gaps

No. of topquality crop

trees perhectare

Profitableharvesting ofwood at risk

Desiredadvance-growth

density:≥ 5,000 trees/ha

Total salvagecutting with

advance-growthprotection

Total salvagecutting

Mini-strip cuttingwithout salvage

Prepare the sitefor reforestation

High risk ofbrowsing by

white-tailed deer

Fill in gaps withwhite

pine andfast growing

species(hybrid poplar

or larch)

Reforest the sitewith white pineand high-value

hardwoods(large seedlings)

Reassess thestand’s condition

in 5 years

Clear cutwithout salvage

Prepare thesite for

reforestation

Select800 trees/ha,

evenlydistributed

or fill in toobtain this

number

Release,straighten or cutback crop trees

as required,and fill in,

if necessary

YES

≥ 4 m

< 4 m

< 10 cm 10 cm < dbh < 24 cm

≥ 250 stems

< 250 stems

YESNO

YES

YES

NO

NO

NO

≥ 24 cm

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In white pine and white spruce stands,better results are obtained when partialcutting and scarification coincide with agood seed year. Shelterwood cutting mustbe adapted to the type of stand. The methodproposed here allows the specific featuresof the following stands to be taken intoaccount:

• balsam fir and spruce stands,

• white pine forests,

• other conifer stands.

Balsam fir and spruce stands

In these stands, shelterwood cuttingopens the canopy sufficiently to allow theyoung conifers to grow freely. It is entirely

suitable for rich balsam fir stands wherethe dense cover slows down the growth ofyoung softwoods, or prevents them frombecoming established.

When shelterwood cutting is carried out inan ice-damaged balsam fir stand, downedtrees and trees broken at a diameter equalor superior to 6 cm should be salvagedfirst. Indeed, we suggest that all defectivetrees should be salvaged, up to a ratio of50% of the stand basal area, to stimulatedesired regeneration while preventingwindthrow21. We recommend harvestingmature trees with butt rot first, togetherwith any intermediate and co-dominanttrees that were more severely damaged bythe ice. In such cases, shelterwood cuttinghas the same effect as average-to-highintensity thinning from below. Care isneeded during salvage operations to avoiddamaging the residual trees which, aswe said earlier, are highly susceptible todecay. Lastly, final salvage cutting shouldbe postponed until the advance-growth iswell-established (around five years), and theyoung trees should be carefully protected.

These young red maple trees damaged by the 1983 icestorm have survived without assistance, but have lost allcommercial value.

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21 We recommend cutting a maximum of 30% to 40% of the initial basal area of stands growing on wet sites or shallow soiland those in which pre-commercial thinning has not yet been carried out. These stands are particularly vulnerable towindthrow. Large rotten balsam fir trees are often carriers of fungi, and may be swollen and cracked at the stump, infestedby black carpenter ants or attacked by woodpeckers.

DID YOU KNOW?

Because of deer pressure on hardwoodadvance-growth, large seedlings or fastgrowing species such as the hybrid poplarmust be planted, so that short-term growthis sufficient to protect the terminal buds.With regard to young high-value hardwoodssuch as oaks and ashes, which may alsobe browsed in the early years of growth,we suggest cutting them back in order tostimulate stump sprouts, which can grow toa height of nearly 2.0 m in a single year.

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42C H A P T E R 2


White pine stands

White pine regenerates badly in moststands that have suffered only slightdamage. Indeed, saplings may be practi-cally non-existent in dense pine forestsgrowing on mesic sites, covered with a thicklitter. Shelterwood cutting has a similareffect to a moderately intense fire, creatingopenings that promote pine regenerationand stand renewal. This treatment is appro-priate for softwood stands with a whitepine basal area of ≥ 30%, in those with> 12 m2/ha of pine or white spruce, and inmixed stands where the percentage of pinetrees is to be maintained or increased.

Ice damage can have the same effect assite preparation carried out to promotenatural seeding of even-aged pine stands.It opens up the forest canopy, mainly byremoving the crowns of co-dominant andmiddle storey trees.

Heavy cutting would favour competingspecies such as balsam fir, red maple,trembling aspen and beaked hazelnut, tothe detriment of the white pine which, aswe said earlier, grows slowly at the saplingstage. However, if only the dead, dying andweakened trees are salvaged, the litteris sufficiently disturbed during hauling toexpose the underlying mineral layer andcreate an adequate seedbed for pine seeds.The light and heat penetrating throughthe small gaps created by the salvagework will stimulate advance-growth andsuppressed pine trees, which must beprotected during harvesting and hauling ofthe wood at risk. Large white or red pinetrees should be preserved as seed trees,even if their crowns have been broken offat a level where the diameter is greaterthan 6 cm. They will continue to grow,and are not likely to deteriorate if thereare no serious wounds in the lower part ofthe bole.

Other softwood standsRaspberry and mountain maple are a

real menace in dense, poorly regeneratedcedar bushes and hemlock forests destroyedby ice. The prognosis is poor for thesestands, which nevertheless regenerate fairlywell when lightly or moderately damaged,because such damage favours cedar andhemlock saplings over competing species.In addition, cedar seeds germinate well onmineral soil or decomposing wood, whilehemlock is able to become established inany type of humus, and even in a thicklitter of leaves or needles.

Shelterwood cutting can therefore becarried out in cedar bushes and hemlockforests that have been damaged but notdestroyed by ice, especially if they are to bemaintained as winter shelters for white-taileddeer. The cutting method recommendedfor balsam fir forests can be applied here.

The boles of white pine trees topped or delimbed by iceare not likely to deteriorate. They are good seed trees,and should be preserved. Ice damage should not be usedas an excuse for cutting down immature pine trees.

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2.3.5.4 Conifer plantations

The best type of treatment for a planta-tion depends on the height of the treesand the potential market for the timber.Plantations can be divided into threecategories:

• young plantations less than 1.5 mhigh,

• pre-merchantable plantations morethan 1.5 m high, and

• merchantable plantations.

Plantations less than 1.5 m high

Most young plantations were protectedby the snow, and ice damage was limitedto bent or broken leader growth. Giventhe high cost involved and the expectedresults, broken leader pruning is notrecommended. Most of the damaged treesshould recover their apical dominancenaturally in the coming years, and theirfuture is not at risk.

Pre-merchantable plantationsmore than 1.5 m high

During the 1998 ice storm, pine andlarch plantations suffered more damagethan spruce plantations. Heavily damagedplantations with trees measuring between1.5 m and 4 m are the most problematical,

since they are not yet commercially valua-ble and the wood at risk cannot be sal-vaged. Jack pine and spruce plantationsstill offer some potential for the future,if they have ≥ 800 quality trees perhectare distributed evenly over the site.In red and white pine plantations, between350 and 500 trees per hectare are required,depending on the site22. Below thesethresholds, total cutting or partial conversioncutting should be carried out. In the lattercase, the most heavily damaged sectorsmade unproductive by the ice stormshould first be identified.

22 Forest producers face a dilemma here, especially if the trees at risk cannot be sold for pulp. Should they convert a heavilydamaged plantation immediately, to obtain maximum production in 50 or 60 years, or should they wait 10 to 20 yearsto salvage around 50% of the volume they would have got without the ice storm? Each case should be analyzed on itsown merits, and the final decision is up to the forest producer. There is no miracle solution to a disaster like the 1998ice storm. The role of the forest advisor is simply to explain the various options to woodlot owners, and leave them tomake the best decision in the circumstances.

DID YOU KNOW?

On the richest sites, intensive cultivationcan produce 300 m3 per hectare of hybridlarch in less than thirty years, and nearly10 m3 per hectare of hybrid poplar per yearafter twenty years.

Jack pine plantation growing on a rich site, destroyed bythe 1998 ice storm. The jack pine should be replaced bya mixture of white pine, hybrid poplars and high-valuehardwoods.

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44C H A P T E R 2


Partial conversion cutting is appropriatewhen the damage is severe but concen-trated in patches. If the patches account formore than 12.5 m2 in spruce plantations(or more than 28.5 m2 in pine forests),restocking is preferable, provided intolerantspecies are avoided. In older plantations,saplings planted in patches measuring lessthan 50 m2 have little chance of catchingup with the dominant trees, and are morelikely to be browsed by hares.

Broken leader pruning may also beuseful in heavily damaged softwood plan-tations, but should be applied only to thetrees that will make up the new stand, i.e.800 spruce or jack pine per hectare, or350 white or red pine per hectare. Thereis a risk that forks or multiple heads willdevelop on trees that have lost the highestpart of their crowns. In the case of thespruce this is corrected naturally, but it canbe a problem in pine trees. In addition,softwoods whose boles have broken at adiameter of more than 6 cm are likely todeteriorate due to discoloration and decay,usually caused by the red heart rot, Stereumsanguinolentum (Alb. et Schw.) Fr. and the

red ring rot, Phellinus pini (Thore: Fr.) A.Ames (4). Red pine trees are less susceptibleto decay, even if a crook forms on the boleand persists for several years. When suchtrees reach maturity, in 35 to 40 years, theirvalue to the sawing industry will probablynot be compromised.

Merchantable plantations

Merchantable plantations containing≥ 800 quality trees per hectare (≥ 500trees if the plantation has already beenthinned), 40% of which are dominant orco-dominant, still offer good potential.Although several such plantations weresalvaged in the spring of 1998, others arethreatened by windthrow. It is thereforeimportant to salvage only the wood at risk,and to leave as many trees per hectareas possible. The risks of windthrow areparticularly high in:

• plantations over 30 years old;

• dense plantations, especially thosegrowing on rich sites;

• plantations in which pre-commercialthinning has not been carried out;

• plantations in which severely damagedtrees were salvaged in the spring of1998 and less than 800 trees perhectare were left standing;

• plantations in which the dominant andco-dominant trees are bent or leaning.

DID YOU KNOW?

Crown-damaged trees have a slowerupward growth rate than neighbouringundamaged trees. They will therefore forma sub-storey in the final crop, and will notproduce much timber. Even so, it is notworth systematically pruning all broken trees,because many will die before reachingmaturity.

Plantations 30 years of age or older in which a significant volume oftimber has been salvaged are at risk for windthrow, especially if pre-commercial thinning was not carried out before the ice storm.

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Red pine plantations in which partialsalvage cutting has been carried out shouldbe restocked so as to increase the newstand’s resistance to any future ice storms.Natural stands containing several storeys(multistoried stands) were damaged lessthan plantations in which all the treeswere the same height (single storied stands).To introduce a multistoried structure in suchplantations, a mixture of red pine, whitepine, white spruce and even larch or hybridpoplar should be planted. A certain numberof high-value hardwoods (300 saplings perhectare), such as red oak or white ash,which are particularly well-suited to richsites, can also be planted.

2.4 OPERATIONS RELATED TOTHE SALVAGE OF DAMAGEDTREES

The following information has beenprovided to help forest advisors answer themain questions raised by forest producersconcerning suitable and unsuitable opera-tions in sugarbushes and plantations andthe salvage of wood at risk. The descriptionof each treatment includes an assessmentof its relevance, the associated constraintsand its anticipated impact on the stand.

Hardwood stands destroyed by ice storm in the Lanaudièreregion in 1983 contain large residual trees that havebecome nesting sites and sources of food for many speciesof mammals and birds, including the pileated woodpecker,Dryocopus pileatus.

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46C H A P T E R 2


Variable results in sugarbushes affectedby dieback – No conclusive results withregard to maple production (23).

Often stimulates the formation of suckersthat are not viable in the longer term –Does not guarantee tree survival – Noimpact on the progression of decay,which is negligible in sugar maples< 40 years old and red maples < 25years of age (16) (17).

Windrowing delays decomposition oftimber by fungi that do not attack livingtrees (4).

Quick recycling of debris by white rotfungi (saprophytic fungi).

Regeneration protects against bolesunscald, summer drying of roots, soildegradation and sapling dieback (9).

Increases the percentage of trees fromdesirable species.

The butternut, shagbark hickory and buroak give good yields on waterside sitesand lowlands – the black cherry, red oak,white ash and bitternut hickory givegood yields on well-drained sites (20)– The white pine manages well on sandysoils.

To be avoided in the short term, becausethe root systems of the trees are intact –To be reassessed in the next few yearsin stands whose succession or stabilityis threatened.

Specialized task, too expensive – Limitedmanpower – Justified to ensure thesafety of people and property – Qualityof work is not guaranteed.

Especially useful in clearing accessroads and tubing – Low yield: thevolume of wood harvested is generally≤ 20 m3/ha.

Profitable if the branches are trituratedin the first year – After a year, sapro-phytic fungi will already have invadedthe dead wood – Expensive operation.

To be avoided in the short term –Release only the tubing and trees with≥ 50% of their crowns remaining, whichcan be tapped without threatening theirhealth.

Useful if there are less than 5,000saplings over 0.5 m high per hectare –Do not plant smaller seedlings, becausethey may not survive.

Useful in heavily damaged forests andtransition forests with dieback growingin rich soil – Requires no site prepara-tion – If browsing is likely to be aproblem, hybrid poplars or high-valuehardwoods, such as oaks or ashes,should be planted, since they growquickly after coppicing.

2.4.1 Hardwood stands

INTERVENTION RELEVANCE / CONSTRAINTS ANTICIPATED EFFECTS

Soil amendments(lime-ashes-fertilizer)

Trimmingof sugarbushes

Salvage of brokenbranches

Loping andscattering

Control orelimination of

advance-growth

Interplanting ofsugar maples in

sugarbushes

Planting ofhigh-valuehardwoodsin tolerant

hardwood stands

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23 Maple producers should consult regional advisors of the ministère de l’Agriculture des Pêcheries et de l’Alimentation onthis subject.

May help improve stand quality.

Production is restored immediately.

Coppicing triggers rapid growth in well-established damaged trees, and allowsproduction to be restored on the site, tothe detriment of undesirable species.

May help control the small mammalsthat attack young trees and tubing –The polypores that grow on the snagsare not a major source of infection forliving trees (3).

The growth, sap flow and healing ofthe trees will be slower in the nextfew years – Sap stain and decay maycompromise long-term maple yields (15).

The use of the site for maple productionshould be reviewed in severely damagedsectors where tree survival is compro-mised.

Allows production to be restored imme-diately in severely damaged patches.

Low yield: under 20 trees per day –Increased risk of wounds on trees usedas anchor points.

Appropriate for young hardwoods under10 years of age – Effective if done inearly spring – Ashes and oaks react wellto this treatment, especially on goodsites.

Preserves shelter for wildlife and provideschoice nesting sites (birds of prey) –Involves some risk to humans, especiallyin sugarbushes used for sap production(see Appendix 4).

Trees with less than 50% of their originalcrowns will not provide much sap –Increased risk of stain and decay,because the taps will take more than5 years to heal.

The operation’s profitability is notguaranteed if maple trees that havepreserved ≥ 50% of their crownsprovide less than 150 taps/ha – Beforetapping severely damaged maples,producers should consider their ownshort-term financial interests and theimpact of the operation on long-termtree health.23

Release of crop trees

Staking ofleaning trees

Coppicingof young icefallen

or severelyleaning hardwoods

Conservationof large snags in

damaged woodlots(3 or 4 snagsper hectare)

Tapping of maplesafter the ice storm23

Reconstructionof the sap

transportationsystem

Windrowing delays wooddecomposition sapro-phytic fungi, such asthe common split gill,Schizophyllum communeFr.

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48C H A P T E R 2


Restocking guarantees optimalproduction.

Straightening will occur naturally in theshort term, and damage is inconse-quential in the medium term.

Eliminates multiple leaders and main-tains apical dominance – High risk ofdecay in softwoods (FSPLHC) if the boleis broken at a level where the diameterexceeds 6 cm.

Provides better long-term yields –Enhances the quality of the butt log.

Useful in plantations under 8 yearsof age, especially in patches of more than12.5 m2 for spruce and more than28.5 m2 for pine – In older plantations,restocking is useful in patches of morethan 50 m2, even though there is a highrisk of browsing.

Useless for trees under 1.5 m highand for larger trees where only the leaderhas been broken.

Necessary for trees between 1.5 m and4 m high that have broken below thesecond-highest internode – Low risk ofdecay on red pines (see Appendix 4). –Straightening of a side branch might besuitable.

Appropriate for young trees leaning atan angle of ≥ 30o – Expensive if thetrees treated are more than 3 m high –Useless if there are more than 800spruce or jack pine trees per hectareor more than 350 red or white pinetrees per hectare.

2.4.2 Softwood plantations

INTERVENTION RELEVANCE / CONSTRAINTS ANTICIPATED EFFECTS

Restocking

Pruning of the brokenleader and / orstraightening ofa side branch

Straightening oftrees and guying

In plantations 8 years of age or older, restocking is useful if trees have been destroyed on sufficiently large patches.Otherwise, the young trees have little chance of survival.

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damage is slight to moderate. For standsthat appear to be heavily damaged,however, the forest advisor should carryout a point sampling survey. If the surveyconfirms the severity of the damage,the advisor and producer should worktogether to see whether it is possible andeconomically profitable to salvage the woodat risk.

3.2 APPROPRIATE SAMPLE SIZEAND SURVEY PERIOD

The ideal period for the survey beginswhen the leaves first appear, since it iseasier at this point to detect dead branchesand assess the recovery rate of survivingbranches, as well as visible tree vigour, anddetermine the tree’s chances of survival.For example, a large number of new shootson a tree that had lost most of its branchesis a good indicator of vigour (see Tables 3and 4).

The proposed sampling method is basedon the forest survey process used forprivate forests. It involves point samplingusing an angle gauge with a basal-areafactor of 2 m2 per hectare24. The numberof sample points varies according to thearea of the stand or part of a stand to besurveyed (Table 6).

The sample points should be distributedat random through the forest strata soas to obtain optimal assessment of dam-age (8). To avoid false measurements, thesample points should be at least 50 m apart,and there should be at least 25 m betweenthe points and the roads or stand margins.

THE EVALUATION METHOD

3.1 MULTIPLE-STAGE SURVEY

Surveying of damaged stands has severalgoals:

• to estimate the severity of the damage;• to establish the extent of the most

severely damaged forest strata;• to obtain dendrometric data represen-

tative of the most severely damagedforest strata;

• to make the necessary silviculturalrecommendations for restoring thestands;

• if necessary, to prepare the salvageplan, taking into account tree vigourand quality, the risk that the timber willdeteriorate, and the type of products;

• to spread salvage operations so as toavoid saturation of certain markets;

• to assess the residual stand’s chancesof recovering and regenerating.

The recommended evaluation method(see Figure 6) is part of a multiple-stagesampling process aimed first at optimizingdata collection so as to make informedsilvicultural decisions, and second, whereapplicable, at salvaging wood at risk first.For example, on-site damage estimatinginvolves assessing the severity of thedamage visually, optimizing the samplingplan through the use of plots and, ifnecessary, defining the sectors wheretreatments are required.

Many requests for service from forestproducers can probably be settled with ashort visit to the woodlot, especially if the

24 To check the reliability of a factor 2 gauge, draw two vertical lines 20 cm apart on a sheet of paper and pin it to a wall.Look at the paper through the gauge, from a distance of 7.07 metres, i.e. the furthest distance (R) for accepting a 20 cmdiameter tree (D) according to the angle count method: Rm ≤ 0.3535 X Dcm (Figure 7).

49C H A P T E R 3

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50C H A P T E R 3

T H E E V A L U A T I O N M E T H O D

FIGURE 6 STEPS IN ASSESSING DAMAGE, FORMULATING APPROPRIATESILVICULTURAL RECOMMENDATIONS AND MONITORING THERECOVERY OF ICE-DAMAGED STANDS

Damaged woodlot withan area of > 4 ha

Carry out stand reconnaissanceand make a global assessment

of the damage

Draft a summary evaluationreport of the damage and

give it to the producer

Heavily damaged stand–

Basal area (BA) of treesto be salvaged > 30%

Mark the trees,including those

to be cut down forroad construction

Inform the producer ofthe work to be carried out

Salvage lumberat risk first

Formulate silviculturalrecommendations

with a view to restoringthe stands and give

them to the producer

Monitor the stand andreassess its potential

in 3 years’ time

Woodlot not admissiblefor salvage of wood

at risk

Prepare the reporton the work and

give it to the producer

Woodlot not admissiblefor the technical

assistance program

Woodlot admissiblefor salvage ofwood at risk

Compile the data usinga specially-designedsoftware package

Close the file

Formulate thenecessary silvicultural

recommendations

First check forthe presence of

vulnerable speciesto adapt harvesting

accordingly

Check the marketsbefore cutting

Determine the bestcutting period and

the type ofequipment required

NO

NO YES

YES

Close the file

Close the file

Carry out a survey inheavily damaged stands(point-sampling method)

51C H A P T E R 3


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Special attention is required whenaccepting or rejecting neighbouring trees(see Figure 7), i.e. trees whose images arepartly hidden in the angle gauge or thosethat intersect at the borderline distancefor a given diameter (8). Less experiencedobservers, if they do not use a tapemeasure to check whether these treesshould be included in the sample, may tendto accept them and hence overestimatestand density.

One point every 5 ha

One point every 10 ha10 + 1 pointevery 5 additional ha

≥ 20,1 ha

3

4

5

6

7

8

9

10

TABLE 6 NUMBER OF SAMPLE POINTS TO BE ESTABLISHED BY STAND AREA

AREA TO BE REQUIRED NUMBER OF NUMBER OF

SURVEYEDSAMPLE POINTS ADDITIONAL POINTS

(HECTARES)

≤ 2 ha

From 2,1 ha to 3 ha

From 3,1 ha to 4 ha

From 4,1 ha to 6 ha

From 6,1 ha to 8 ha

From 8,1 ha to 12 ha



DID YOU KNOW?

At least two point samples are requiredper hectare to represent an uneven-agedhardwood stand structure (8). However,it is better to sacrifice accuracy in orderto optimize sampling in the areas to besurveyed. Care is needed to ensure thatestimates are not biased.

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52C H A P T E R 3


3.3 THE VARIABLES

During the survey, all merchantable trees(dbh ≥ 9.1 cm) in the sample point mustbe measured using the angle gauge, eventhose that are broken under the crown,uprooted, icefallen or leaning.

In addition, the saplings and seedlingsto be preserved as crop trees must beidentified in sectors where shelterwoodcutting is required. These estimates,expressed as a number of trees per hectare,can be made visually if regeneration isvery abundant or very sparse. In all othercases25, the seedlings and saplings mustbe counted in circular sample plots. Thesize of the plots will vary according to thedevelopment stage of the advance-growth:

• 1/100 ha (100 m2 or 5.64 m in radius)for saplings with a dbh of 1.0 cm to9.0 cm;

• 1/350 ha (28.6 m2 or 3.02 m inradius) for tolerant hardwood seedlingswith a dbh of < 1.0 cm and a heightof ≥ 0.5 m, and softwood seedlings≥ 15 cm high.

The form used to note the data obtainedfrom the point sampling appears inAppendix 5. The forestry variables usedon the form are as follows:

• species;

• diameter breast height (dbh),expressed in 2 cm intervals;

• tree vigour and quality categories(see section 2.2);

• the percentage of residual crown,taking into account the branchesthat have formed since the ice storm(expressed in 10% intervals);

• the position of each tree studied inthe sampling point;

• the number of seedlings and saplingsof desirable species, per hectare26;

• bole shape (see the diagrams inAppendix 2);

• the type of stand and the type ofproduct it is intended for;

• the silvicultural treatments appliedbefore the ice storm.

25 Plots must be established when it is not clear, from a visual inspection alone, that the advance-growth is sufficiently dense,i.e. in excess of 5,000 viable hardwoods or sugar maples per hectare, excluding small hardwood saplings less than 0.5 mhigh and undesirable species such as balsam fir, beech, red maple and trembling aspen (see section 3.4).

26 This information is only useful in severely damaged sectors where shelterwood cutting is required.

An accurate forest survey is vital in identifying the most severely damagedsectors, assessing the trees’ chances of survival, making silviculturalrecommendations, salvaging lumber at risk and restoring the stand.

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53C H A P T E R 3


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FIGURE 7 SAMPLE POINT AND SAMPLE PLOTS ESTABLISHED TO ESTIMATECROWN COVER, STAND DENSITY AND ADVANCE-GROWTH

R= 5.64 m (1/100 ha)

Sapling plot

BITTERLICH FORMULA

Rm ≤ f x Dcm

f= angle gauge constant

D= diameter of tree (dbh cm)

R= critical distance (m) betweenthe centre of the plot andthe centre of the tree

R < 10.96 m

R < 14.50 m

R <

28.

63 m

R <

3.9

2 m

R= 3.02 m (1/350 ha)

Seedling plot

10 cm

30 cm

80 cm

40 cm

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54C H A P T E R 3


3.4 DATA COMPILATION

The survey data can be used to obtainan overview of the damage and quantifythe volume of wood at risk for each productcategory. Based on this information, forestadvisors can recommend appropriate silvi-cultural treatments and, where applicable,draw up a salvage plan. Marketing consid-erations must always be taken into accountbefore any intervention. In addition, as wesaw earlier, it is not possible to salvage allthe wood at risk in a single operation, sincethis hinders stand recovery. Before a salvageprogram is implemented, the followingcompilations, obtained using a specially-designed software program, should betaken into account:

• the basal area of living merchantabletrees;

• the basal area of dead merchantabletrees;

• the basal area of merchantable aspensthat have retained 60% or less of theircrowns;

• the basal area of uprooted, icefallenor severely leaning trees;

• the basal area of merchantable soft-woods broken at a level where thediameter is ≥ 6 cm, except maturered and white pines;

• the basal area of merchantable tole-rant or semi-tolerant hardwoods thathave retained between 10% and 20%of their crowns;

• the basal area of merchantable hard-woods that have retained ≤ 10% oftheir crowns;

• the volumes of wood to be salvaged(veneer logs, saw logs, pulp, etc.) andthe order in which harvesting shouldtake place;

• the residual basal area and thecumulative thinning rate;

• the density of desirable softwood andhardwood advance-growth.

Table 7 provides an example of a toolthat may be extremely useful when decid-ing on the silvicultural treatment requiredand the volume of wood to be harvested,based on the priorities established inTable 5. It can be drawn up after compilingthe data collected in accordance with theabove instructions (see Figure 6).

DID YOU KNOW?

Simply increasing the number of samplepoints is not enough to improve the accu-racy of the survey. Special attention mustalso be paid to the stratification of thesectors surveyed and the quality of thedendrometric data gathered. In addition,the sample points must be selected on astrictly random basis.

55C H A P T E R 3


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TABLE 7 SALVAGE PROGRAM ESTABLISHED ACCORDINGTO THE VALUE OF THE WOOD AT RISK

VOLUME (m3 / ha) BASAL AREA (m2 / ha)

No. of sample points: 6

Merchantable basal area and % of hardwoods otherthan aspens with ≤ 10% of residual crown 2.00 m2 / ha 10.2%Merchantable basal area and % of hardwoods otherthan aspens with 10% to 20% of residual crown 4.67 m2 / ha 23.7%

Merchantable basal area and % of aspens with≤ 60% of residual crown 0.00 m2 / ha 0.0%

Merchantable basal area and % of softwoods broken at morethan 6 cm, except mature white and red pines 0.67 m2 / ha 3.4%

Merchantable basal area and % of hardwoods other thanaspens with > 20% of residual crown 9.67 m2 / ha 49.2%

Total merchantable basal area (T.M.B.A.) 19.67 m2 / ha

Merchantable basal area and % of icefallen trees/T.M.B.A. 1.33 m2 / ha 6.8%

Basal area and % of merchantable trees in good condition 12.3 m2 / ha 62.7%Basal area and % of trees at risk 7.3 m2 / ha 37.3%

Saw logsveneer logs

0.5

1.7

1.5

0.0

3.6

2.1

3.2

0.0

0.0

5.0

2.9

Pulp

2.0

3.5

2.5

6.1

0.0

14.2

3.1

0.0

0.0

13.4

12.9

0.0

2.0

0.0

0.0

8.3

0.0

1.9

7.4

11.7

19.2

Total

2.5

3.5

4.2

7.6

0.0

17.9

5.2

0.0

0.0

13.4

16.2

0.0

2.0

0.0

0.0

8.3

0.0

1.9

12.4

14.6

19.2

Cumulative

volume

2.5

6.1

10.2

17.8

17.8

35.7

40.9

40.9

40.9

54.3

70.5

70.5

72.5

72.5

72.5

80.8

80.8

82.7

95.1

109.7

128.9

%cumulative

2%

5%

8%

14%

14%

28%

32%

32%

32%

42%

55%

55%

56%

56%

56%

63%

63%

64%

74%

85%

100%

B.A.

0.3

0.7

0.7

1.0

0.0

2.3

0.7

0.0

0.0

2.3

2.0

0.0

0.3

0.0

0.0

1.7

0.0

0.3

1.7

2.0

3.7

cumulative

B.A.

0.3

1.0

1.7

2.7

2.7

5.0

5.7

5.7

5.7

8.0

10.0

10.0

10.3

10.3

10.3

12.0

12.0

12.3

14.0

16.0

19.7

%cumulative

2%

5%

8%

14%

14%

25%

29%

29%

29%

41%

51%

51%

53%

53%

53%

61%

61%

63%

71%

81%

100%

ResidualB.A.

19.3

18.7

18.0

17.0

17.0

14.7

14.0

14.0

14.0

11.7

9.7

9.7

9.3

9.3

9.3

7.7

7.7

7.3

5.7

3.7

0.0

Harvest

100%

100%

100%

80%

0%

70%

100%

0%

0%

40%

0%

0%

0%

0%

0%

0%

0%

0%

0%

0%

0%

III 0% Tolerant hardwoods Dead Quality

IV 0% Tolerant hardwoods Dead Defective

VIs 0% Softwoods Dead Defective

III ≤ 10% Tolerant hardwoods Weak Quality

III ≤ 60% Aspens Weak Quality

III ≤ 20% Tolerant hardwoods Weak Quality

VI Broken top Softwoods Weak Defective

IV ≤ 10% Tolerant hardwoods Weak Defective

IV ≤ 60% Aspens Weak Defective

IV ≤ 20% Tolerant hardwoods Weak Defective

III > 20% Tolerant hardwoods Weak Quality

III > 60% Aspens Weak Quality

IV > 20% Tolerant hardwoods Weak Defective

IV > 60% Aspens Weak Defective

II > 60 % Aspens Vigorous Defective

II > 20% Tolerant hardwoods Vigorous Defective

I >60% (≥24cm) Aspens Vigorous Quality

I >60% (<24cm) Aspens Vigorous Quality

V 100% Softwoods Vigorous Quality

I >20% (≥24cm) Tolerant hardwoods Vigorous Quality

I >20% (<24cm) Tolerant hardwoods Vigorous Quality

Saw and veneer volumes to be harvested: 8.0 m3 / ha Basal area to be harvested: 5.7 m2 / haPulp volume to be harvested: 31.3 m3 / ha Residual basal area: 14.0 m2 / haTotal volume to be harvested: 39.4 m3 / ha % of basal area to be harvested: 29%Residual volume: 89.5 m3 / ha% of volume to be harvested in priority: 31% Equipment recommended for harvesting:% of basal area of trees at risk: 37% Manual logging - skidderAdmissible for assistance program: Yes Desirable advance-growth: Hardwoods: 10,200 saplings / ha

Softwoods: 2,125 saplings / ha

Categorie Residual Species Vigour Conditioncrown

area, i.e. 5.7 m2/ha or 39.3 m3/ha of thestanding volume, leaving any good blackcherry and white ash specimens standing,since they generally recover well. It shouldbe noted that not all the wood at risk(7.3 m2/ha) is systematically harvested.After the first partial cut, the stand wouldhave a density of nearly 14.0 m2/ha or89.5 m3/ha, which is the minimumrecommended density for this type ofstand (see Figure 4).

If all the trees at risk were salvaged, thebasal area would be reduced to 11.7 m2/ha,which is unacceptable in forestry terms. Itis important to leave at least some standingtrees with less than 20% of residual crown,since they have a good chance of recoveringin the next few years.

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56C H A P T E R 3


In the case shown in the table, 100% ofthe dead trees intended for lumber or pulpproduction (10.2 m3/ha) and all the weaksoftwoods (5.2 m3/ha) would be harvestedin priority, during the first stage. As thereis some leeway with regard to the residualbasal area required, the forest advisorcould set a harvesting rate to allow for thesalvage of some weaker trees. In addition,40% of the weak and defective hardwoods(40% of 13.4 m3/ha = 5.4 m3/ha), 80% ofthe birch, maple and other quality toleranthardwoods with ≤ 10% of their crownsremaining (80% of 7.6 m3/ha = 6.1 m3/ha)and 70% of those with ≤ 20% of theircrowns remaining (70% of 17.9 m3/ha =12.5 m3/ha) would be harvested. Thiswould mean removing 29% of the basal

WarningMarking is an importantoperation that should becarried out carefully and

meticulously by experiencedforestry technicians.

It is this step that will determinethe success of the operation.

Declining sugarbush, poorly regenerated, invaded bybracken ferns and likely to disappear because of over-intensive cutting after the 1983 ice storm in the Lanaudièreregion.

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In applying a salvage program as shownin Table 7, it is important to avoid woundingthe trees with the machinery or harvestingunmarked trees. During marking, wepropose reducing the volume of wood tobe salvaged by 10% (10% of 39.4 m3/ha,or approximately 4 m3/ha) to compensatefor the inevitable losses: trees cut down bymistake or to create hauling trails, etc. (18).

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57

CONCLUSION

Sugar maples severely damaged by the 1983 ice storm.Nearly half the crown of the tree that was entirely destroyedhas grown back.

This tree was broken at a y-junction and has lost all itsvalue for timber production. However it still retains anacceptable potential for sap production.

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Forest producers tend to underestima-te a stand’s ability to recover, even ifit has been very severely damaged.

There is no immediate need to cut downtrees. Indeed, it is best to wait a few years,to assess their reactions and see whethernew branches are formed. It will then beeasier to make informed decisions. Naturewill dictate the measures required (6).

Special steps must be taken to ensureworker safety in ice-damaged stands. Forexample, forestry workers should never beleft unsupervised.

Everyone working in the stand must beaware of the safety rules to be appliedduring the salvage operations proposed inthis document (12 and 13). First, piles ofbranches and uprooted or leaning treesmay hinder circulation in the forest. Second,once the leaves appear it may be difficultto see lodged trees and hanging branchesthat are likely to fall during salvage work(13). Lastly, leaning trees are always adanger to forestry workers during logging,even after several years.

The ice storm that devastated Québec’sforests in 1998 left forest and maple sapproducers in a very difficult situation.

C O N C L U S I O N

After the disaster, the damage had to beassessed, a salvage program for woodat risk drawn up, and practical solutionsproposed for the restoration of damagedstands. This document is the result of acollective effort. Those involved pooledtheir knowledge to answer questionsconcerning stand restoration and to solvethe problems of marketing salvaged wood.The silvicultural treatments proposed inthis document have been studied carefully,and their short and long-term impacts ontree health and the ecological integrity ofstands have been assessed. The documentcontains all the technical information atour disposal to help alleviate the effects ofthe 1998 ice storm and any other naturaldisasters that may affect our forests in thefuture.

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Manual removal of bent or broken trees and trees containing brokenand snagged branches can be very risky for forestry workers engaged insalvage operations.

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C O N C L U S I O N

MRN, Direction de la conservation des forêtsLimits of regional county municipalities

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59

SELECTED REFERENCES

(1) Anonyme. 1991. Classification des tiges d’essences feuillues – Normes techniques.Gouvernement du Québec, ministère des Ressources naturelles, Serv. des inventairesforestiers. Publ. no RN95-3017, 72 p.

(2) Anonyme. 1992. Bois de déroulage : guide de production pour les propriétairesforestiers. Industrie Manufacturière Mégantic et Groupe Trans-Forêt, 32 p.

(3) Anonyme. 1998. La conservation des chicots. Le Progrès forestier, hiver 1998: 6-7.

(4) Boulet, B. 1995. Impacts de la carie des arbres et stratégie d’intervention dans lemilieu forestier. L’Aubelle, 111: 1-12.

(5) Boulet, B. 1998. Le verglas de 1998: les conséquences probables dans les peuplementsforestiers touchés. L’Aubelle, 124: 10-14.

(6) Boulet, B. 1999. Le verglas de janvier 1998: les forêts encore sous le choc. Le ProgrèsForestier, hiver 1998: 6-7.

(7) Chabot, M. et al. 1998. Dommages causés à la forêt par le verglas de janvier 1998.(Résultats préliminaires d’une reconnaissance aérienne réalisée entre le 19 janvieret le 4 février 1998). Gouvernement du Québec, ministère des Ressources naturelles,Direction de la conservation des forêts, 12 p. (rapport interne).

(8) Grenier, Y., L. Blais et E. Lavoie. 1990. Aire minimum d’échantillonnage ounombre de points de prisme nécessaires pour établir la structure d’un peuplementinéquienne. Can. J. For. Res., 21: 1632-1638.

(9) Houston, D. R., D. C. Allen et D. Lachance. 1990. Aménagement de l’érablière :guide de protection de la santé des arbres. Serv. can. for., Centre de foresterie desLaurentides, Sainte-Foy (Qc). Rapport no LAU-X-92F, 59 p.

(10) Huot, M. et B. Boulet. 1999. L’enrichissement à l’aide du pin blanc : un traitementde plus en plus populaire. Le Progrès forestier, printemps-1999: 45-46.

(11) Majcen, Z., Y. Richard, M. Ménard et Y. Grenier. 1990. Choix des tiges à marquerpour le jardinage d’érablières inéquiennes – Guide technique. Gouvernement duQuébec, ministère de l’Énergie et des Ressources. Sainte-Foy (Qc), Mémoire no 96.

(12) Picher, R. et al. 1995. Abattage manuel. Gouvernement du Québec, CSST, 56 p.

(13) Picher, R. 1992. Chicots de feuillus – Danger, mesure du risque et actions deprévention. Gouvernement du Québec, CSST, 40 p.

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60

(14) Pin, D. et P. Dan Vlasiu. 1998. Les fentes chez l’érable à sucre. Sylve Consultant,Éd. à Mains Nues inc., Lévis, 17 p.

(15) Rodrigue, S. 1998. Guide d’aménagement des érablières. Syndicat des producteursde bois de la Beauce, Saint-Georges. 35 p.

(16) Spaulding, P. et A. W. Bratton. 1947. Decay Following Glaze Storm Damage inWoodlands of Central New York. J. Forestry, 44(7): 515-519.

(17) Shigo, A. et W. C. Shortle. 1979. Compartimentalization of Discolored Wood ofRed Oak. Phytopathology, 69: 710-711.

(18) Smith, H. C. et N. L. Lamson. 1982. Number of residual trees. A guide for selectioncutting. USDA For. Serv., Broomall, Pa, Northeast For. Exp. Stn., Gen. Rep. NE-80. 33 p.

(19) Trottier, F. 1998. Inventaire forestier du territoire touché par le verglas de janvier1998. Partie 1: Estimation des volumes de bois à récupérer. Gouvernement duQuébec, ministère des Ressources naturelles, Dir. ass. tech., Rapport déposé à laCommission Nicolet, sept. 1998, 13 p.

(20) Truax, B. 1996. Restauration écologique des forêts de feuillus par la plantation.Chapitre 9, pp. 119-134 in Cantin, D. et C. Potvin, 1996. L’utilisation durable des forêtsquébécoises: de l’exploitation à la protection. Sainte-Foy (Qc), Presses Univ. Laval, 157 p.

(21) Truax, B. 1999. Plantation de feuillus par enrichissement de vieilles friches et deforêts dégradées. Le Progrès forestier, automne 1999: 24-26.

(22) Vooris, N. G. 1986. Sugarbush management in young stands: effects of crop treethinning. North. J. Appl. For., 3: 106-108.

(23) Walters, R. S. 1982. Sugarbush management. pp. 25-37 in Sugar maple research:sap production, processing, and marketing of maple syrup. USDA For. Serv.,Northeastern For. Exp. Stn., Gen. Tech. Rep. NE-72.

61

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APPENDIX 1 RESIDUAL CROWN OF ICE-DAMAGED TREES

Sectionto be

assessed

Sectiondestroyed

1.1

1.2

1.3

1.4

Lower partof crown

Sectiondestroyed

Sectiondestroyed

Sectiondestroyed

Sectionto be

assessed

Sectionto be

assessed

Sectionto be

assessed

Lower partof crown

Lower partof crown

Lower partof crown

Residual crown: 65%

1

2

3

4

Residual crown: 25%

Residual crown: 45%

Residual crown: 70%

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APPENDIX 2 BOLE DEFORMATIONS IN ICE-DAMAGED TREES

2.1 2.2

40o

StraightCode: S

Bent or leaningCode: L

IcefallenCode: I

BrokenCode: B

80o

2.3 2.4

1 2

3 4

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APPENDIX 3 ASSESSING THE SEVERITY OF BOLE WOUNDSON ICE-DAMAGED TREES

Damaged circumference: 20% + 45% = 65%Wounds on three faces

Side 120% of the circumference

Side 1 Side 2

Side 245% of the circumference

Lower partof crown

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APPENDIX 4 CHARACTERISTICS OF SPECIES: HEARTWOOD RESISTANCETO DECAY, SHADE TOLERANCE, LIFE SPAN, GROWTH RATEAND POTENTIAL USE BY WILDLIFE(Taken from Boulet and Sirard, under preparation)

Upwardgrowth

rate(cm / yr)

30-60< 30> 6030-6030-6030-6030-60> 60> 60> 60< 30> 60> 60< 3030-6030-6030-60

< 30< 30> 60< 3030-60> 60< 30> 60> 6030-6030-60< 30< 3030-60< 3030-60> 60> 60> 60> 60> 60> 6030-6030-6030-60

Species Life span

(years)

> 200> 200100-200> 200> 200> 200100-200< 100100-200> 200> 200< 100< 100> 200100-200> 200100-200

100-200> 200< 100> 200> 200100-200100-200< 100< 100100-200100-200100-200> 200> 200> 200100-200< 100100-200< 100< 100< 100< 100< 100100-200100-200

Porosityof wood1

—————rrr

s.r.s.r.rrrrrrr

—————dddddddrrdrrr

s.r.d

s.r.dddr

Shadetolerance2

Attractionfor wildlife

(No. of species)

> 50> 5015-2525-50> 50< 5< 5

25-50> 505-14> 50< 5< 5> 50> 50> 50< 5

25-5025-50> 5015-255-14> 50> 50> 5025-50> 50> 505-1415-25> 5025-505-145-145-145-1425-5025-5025-5015-25< 515-25

1 Hardwood porosity: d: diffuse; s.r.: semi-ring porous; r: ring porous.2 Shade tolerance: : highly intolerant; : intolerant; : semi-tolerant; : tolerant; : highly tolerant.

RESISTANCE TO DECAY — HIGH* OR AVERAGE¬

Red pine*Junipers*Tamarack ¬Douglas fir ¬Eastern white pine ¬American chestnut*Kentucky coffeetree*Red mulberry*Black cherry*Black walnut*White oak*Northern catalpa*Black locust*Bur oak*Swamp white oak ¬Northern red oak ¬Honeylocust ¬

Balsam fir*White spruce*Jack pine*Eastern hemlock*Northern white-cedar*Red maple ¬Sugar maple*Silver maple*Alders ¬White birch ¬Yellow birch*Ironwood*Hickories*Hackberry*American beech ¬White ash*Black ash*Green ash*Butternut*Poplars ¬Plum and cherry trees ¬Willows ¬American mountain-ash*American basswood*American elm*

RESISTANCE TO DECAY — LOW* OR NIL¬

65

MA

NA

GE

ME

NT

O

F

IC

E

ST

OR

M

DA

MA

GE

D

ST

AN

DS

IC

E

ST

OR

M

APPENDIX 5 ICE DAMAGE SURVEY FORM

LOT: RANGE: MUNICIPALITY:

SECTOR: AREA:

SURVEYOR: DATE:

SURVEY LINE NO.: PLOT NO.:

SPECIES DBH RESIDUAL

CROWN

BOLE

SHAPE1CATEGORY OF

VIGOUR/QUALITY

I II III IV1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20Total :

Tree no.:

Species:

Distance:

Type of stand:

Location (GPS file no.):

Silvicultural treatment:

Past:

Prescription3:

Tapped sugarbush: ❏

Desirable advance-growth:(straight sapling, unhindered growth,debris free)Main species:

Recent harvest:

- Advance-growth: - abundant: ❏ - sparse: ❏

Seedlings / ha Saplings / ha Total / ha

1. Bole shape:

S: Straight

L: Leaning

I: Icefallen

B: Broken under the crown

2. Note(s):

No. of faces wounded

D: Dieback

W: Windthrow

De: Significantdecay in bole

3. Silvicultural prescription:

PS: Partial salvage

TS: Total salvage

TSAGP: Total salvage withadvance-growth protection

2STS: Two-step total salvage

MSC: Mini-strip cutting

SC: Sanitation cutting

GSC: Shelterwood cutting

NOTE(S)2

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MANAGEMENT OF ICE STORM DAMAGED STANDS