Small Grain Disease

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The National SustainableAgriculture Information Service,ATTRA (www.attra.ncat.org),was developed and is managedby the National Center forAppropriate Technology (NCAT).

The project is funded througha cooperative agreement withthe United States Departmentof Agricultures Rural Business-Cooperative Service. Visit theNCAT website (www.ncat.org/sarc_current.php) formore information onour other sustainableagriculture andenergy projects.

1-800-346-9140 www.attra.ncat.orgA project of the National Center for Appropriate Technology

Susan Tallman, CCA

NCAT Agronomist

Published April 2011

NCAT

IP388

Contents

Disease and Insect Management

in Organic Small GrainsIntroductionManaging the complex bio-logical system of an organicsmall grain farm can be achallenge, particularly interms of disease and insectmanagement.

Because synthetic fungi-

cides and insecticides aregenerally not allowed inan organic system, preven-tion is the main strategyfor avoiding pest problems.Successful prevention usu-ally involves many differentstrategies in combination, rather than relying ona single one.

Te purpose of this publication is to outline var-ious strategies that make up a good organic dis-

ease and insect management plan, as well as todescribe some specific diseases and insects thataffect small grain crops. Although this publica-tion pertains to various regions of the country,the main focus is on the Plains stateswheremost organic small grains are grown.

The National OrganicProgram StandardsTe National Organic Program Regulations sec-tion 205.206 specifies the crop pest, weed, and

disease management practice standard as a hier-archy of practices (NOP, 2010). Te foundationof any organic pest-management strategy is croprotation, sanitation, and cultural practices suchas variety selection.

Te second tier in the hierarchy is mechanicaland physical methods that may include intro-duction of natural predators, natural traps, andrepellents, and development of habitat for natu-ral enemies.

Te third tier of the hierarchy is the use of bio-logical or allowed synthetic substances for thecontrol of pests. Tese methods are allowed only(and are most effective) when the foundationalpractices in the first and second tiers are inplace. Tese third-tier measures are for use once

a disease or pest is present, after the first levelsof prevention strategies have failed. Understand-ing foundational biological principles, rather thansimply substituting organic inputs for conven-tional ones, is a key to good organic management.

Disease Management

Climate and Locationwo important determining factors for diseasedevelopment are climate and location. Areas

with low humidity generally have much less dis-ease pressure than areas with high humidity,since it usually takes six to 12 hours of continualleaf wetness for a fungal leaf disease to develop(Burrows, 2009). Tis probably explains whythe Great Plains states are the top organic-grain-producing states in the nation. If you live in aregion of the United States with high humidityand heavy disease pressure, you need to considercarefully whether organic small-grain produc-tion is right for you.

Organic winter wheat at the Quinn Farm, Big Sandy, MT. Photo: Susan Tallman,

NCAT

Introduction ......................1

Disease Management ....1Specific GrainDiseases ..............................3

In-crop Insects ..................9

Stored-grain Insects .....11

Conclusion ...................... 14


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Page 2 ATTRA Disease and Insect Management in Organic Small Grains

205.206 (a)

Crop RotationSanitation

Cultural Practices

205.206 (e)

Biological sub-stance, or synthetic

included on the NationalList; must be documentedon Organic System Plan.

Level 1

205.206 (d)

Management practices which suppressthe spread of disease organisms; or

application of nonsynthetic biological,botanical, or mineral inputs.

Level 2

Level 3

Figure 1. Organic CropDisease ManagementPractice Standard.

year. Regular use of Certified seed will help man-age seed-borne diseases such as smut and bunt.

Certified Seed

The term Certified seed does not refer to certi-

fied organic. Rather, it denotes seed that is pro-

duced under conditions that assure its purity and

vigor. Certified seed is produced from founda-

tion, registered, certified, or other approved seed

stocks. This seed is two generations from founda-tion seed. Certified seed cannot be used to pro-

duce Certified seed again without the approval

of the state certification agency, which can

approve production only under extreme condi-

tions (Ulmer and Stuber, 1997).

Double-certified seed is seed that is considered

both Certified (from Foundation seed) and cer-

tified organic. Currently, the chance of locat-

ing double-certified seed is very slim (Zwinger,

2009). However, the Organic Seed Alliance con-

tinues to work toward increasing the quality and

amount of organic seed used in field crop pro-duction. Their website is www.seedalliance.org.

Further Resources

Selecting Quality Seed of Cereal Grains. 1990.

NDSU Extension circular, A-500. J.L. Helm and L.A.

Spilde.

www.ag.ndsu.edu/pubs/plantsci/smgrains/a500w.

htm

RotationRotation is another tool for disease management.Fungal diseases such as tan spot and Septoriasurvive on stalk residue. Fusarium head blight isalso carried in the residue of wheat, barley, andcorn. Moving to a legume or oilseed in rota-tion will help break this disease cycle. (For moreinformation on designing an organic small grainscrop rotation, consult the ARA publicationOrganic Small Grain Production Overview.)

Delayed PlantingPlanting when soil temperatures are warmer canhelp manage soil-borne fungi such as Pythiumand Rhizoctonia. ypically, these fungi are moreof a problem in larger-seeded crops such as gar-banzo beans and corn. However, if you have hadproblems with these diseases in the past, try delay-ing your spring planting until soil temperaturesare warm enough to allow optimal seed germi-nation and plant establishment (Burrows, 2009).

Cultural Practiceshere are several cultural practices to helpprevent diseases, including variety selection,delayed planting, and irrigation timing.

Resistant VarietiesTe first step in disease management is selectinga variety with disease resistance. Choose variet-ies that are specific to your area and that havebeen bred with resistance to local diseases. For

example, stem rust is a common grain diseasethat can be managed by good variety selection.State Extension stations conduct annual varietytrials that list the resistance levels of differentvarieties. Check their annual reports for recom-mendations.

While resistant varieties provide the first line ofdefense, there is no one variety of grain that isresistant to every disease. Prioritize your selec-tion of resistant varieties by the diseases mostcommon in your area.

Seed QualityFind the plumpest, highest-germinating seedpossible, and plant in high density to accountfor any loss of stand due to damping off. Whenpossible, select Certified seed from a reputabledealer. Make sure the seed is a pure variety, andthat you know what you are buying. In general,Certified seed should be purchased every third
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content exceeds 12%. If there is concern aboutthe grains moisture content, use aeration in thebin to dry the grain. High moisture levels andelevated bin temperatures lead to mold, graindeterioration, and insect infestation.

Further Resources

Grain Moisture Content Effects and Man-

agement.NDSU Extension publication AE-905

(Revised). 1995. Dr. Kenneth J. Hellevang, PE,Extension Agricultural Engineer. www.ag.ndsu.

edu/pubs/plantsci/crops/ae905w.htm

Energy-Efficient Grain Drying Resources.

ATTRA.www.attra.ncat.org/attra-pub/graindrying.

html

Buckwheat Harvesting, Drying, and Storage.

Dr. Bill Wilcke. www.nysaes.cornell.edu/hort/

faculty/bjorkman/buck/guide/dry.html

Using Farm Moisture Testers.Iowa State Exten-

sion, PM-1633. 1995. Charles Hurburgh. www.

extension.iastate.edu/Publications/PM1633.pdf

Specific Grain DiseasesSpecial thanks to Dr. Mary Burrows and Dr. BillGrey of Montana State University for providinginformation on specific grain diseases and theirmanagement.

In addition to general cultural practices, thereare some specific diseases of which organic smallgrain growers should be aware. Some are rela-

tively harmless and will only slightly decreaseyields. Others are more serious and can lead tocrop failure or be detrimental to livestock andhuman health.

Proper identification of these serious diseases isimportant in order to decide the best manage-ment strategy. What to do with the crop willdepend on weather conditions, the pathogenlevel, and the amount of susceptible host mate-rial. In most cases, the presence of disease willsimply reduce the crop yield. In extreme cases,the diseased portion of the crop should be termi-nated to reduce potential infection of other areas.

It is difficult to make specific threshold andmanagement recommendations for each diseasewithin the scope of this publication. Land-grantuniversities often have plant pathology labsthat will diagnose a disease and provide specificmanagement recommendations. Contact yourlocal Extension agent for more information.

Irrigation TimingIf you are growing grains using irrigation, donot irrigate during the flowering stage. Flower-ing is the susceptible period for Fusarium headblight and ergot. If you are able to control tim-ing of water application, do not water duringthis period.

Crop ScoutingCrop scouting is an essential part of diseasemanagement. Te earlier you can detect dis-eases in the field, the more time you have torespond. Hone your skills in disease diagnosis.Local Extension agents often have identificationguides available in print and online versions.Likewise, most land-grant universities haveExtension pathologists on staff and diagnosticlabs where growers can send any questionableplants for diagnosis.

If you discover a disease in your fields, there areseveral options. If the disease is not a seriousproblem for further infestation, or harmful forhuman or animal consumption, you may choosesimply to live with the reduced yield. Anotheralternative is application of biological or allowedsynthetic substances. Check the ARA Biora-tionals: Ecological Pest Management Database(www.attra.ncat.org/attra-pub/biorationals/) forallowed organic substances for specific diseases.Extreme cases may require terminating theaffected portion of the crop before the diseasegets out of hand.

Further Resources

Contact your local Natural Resource Conser-

vation Service (NRCS) office for conservation

planning and programs that offer assistance

in implementing conservation practices. Assis-

tance is available through the Environmental

Quality Incentives Program (EQIP) for planning

and implementing a wide range of conserva-tion practices such as an Integrated Pest Man-

agement plan for organic production. Contact

your local NRCS field office for information.

Storage EnvironmentFinally, manage for storage diseases in addi-tion to in-crop diseases. Storage mold can bemanaged by constantly checking grain mois-ture during harvest. Hand-held grain moisturemeters are available to purchase (Grey, 2009).Discontinue harvest when the grain moisture
http://www.ag.ndsu.edu/pubs/plantsci/crops/ae905w.htmhttp://www.ag.ndsu.edu/pubs/plantsci/crops/ae905w.htmhttp://www.ag.ndsu.edu/pubs/plantsci/crops/ae905w.htmhttp://www.attra.ncat.org/attra-pub/graindrying.htmlhttp://www.attra.ncat.org/attra-pub/graindrying.htmlhttp://www.attra.ncat.org/attra-pub/graindrying.htmlhttp://www.nysaes.cornell.edu/hort/faculty/bjorkman/buck/guide/dry.htmlhttp://www.nysaes.cornell.edu/hort/faculty/bjorkman/buck/guide/dry.htmlhttp://www.nysaes.cornell.edu/hort/faculty/bjorkman/buck/guide/dry.htmlhttp://www.extension.iastate.edu/Publications/PM1633.pdfhttp://www.extension.iastate.edu/Publications/PM1633.pdfhttp://www.extension.iastate.edu/Publications/PM1633.pdfhttp://www.extension.iastate.edu/Publications/PM1633.pdfhttp://www.nysaes.cornell.edu/hort/faculty/bjorkman/buck/guide/dry.htmlhttp://www.attra.ncat.org/attra-pub/graindrying.htmlhttp://www.ag.ndsu.edu/pubs/plantsci/crops/ae905w.htm


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Spores are spread by wind and rain, with barleyresidue serving as the main source of infectionfor subsequent crops.

Organic control practices to prevent Net Blotch:

Use resistant cultivars.

Bury crop residue and destroy volun-teers.

Use balanced applications of nitrogenand phosphorus. Heavy nitrogen appli-cations create conditions favorable tooutbreaks of this disease.

Follow a crop rotation that includes atleast two years of non-susceptible hosts.Barley should not follow barley, partic-ularly if disease levels were high the pre-vious year.

If barley must be grown in two succes-sive years, use a susceptible cultivar the

first year and a resistant type the second. Use pathogen-free seed if possible

(Skoglund, 2010).

ScaldLike the blotch diseases, scald is a fungal leafdisease that mainly affects barley. Some resis-tant barley cultivars are available. Crop rotationand plowing under diseased barley residue seemto be the best methods of control for situationswith high infestation (Maloy and Inglis, 1993).

RustTere are three rust diseases of wheat in theUnited States: leaf (or brown) rust, stem (orblack) rust, and stripe (or yellow) rust. Teserusts have a long history in the cultivation ofwheat and have been managed with the develop-ment of resistant varieties. However, accordingto North Dakota State University researchers,Te leaf rust pathogen is dynamic, and races areconstantly changing. Varieties formerly consid-

ered resistant can become susceptible if new rustraces develop. Resistance levels are updated eachyear for varieties (McMullen et al., 2008a). Forthis reason, its best to check variety resistanceratings each year before planting.

Rust spore infection is promoted by long periodsof dew on the foliage. Terefore, high-humid-ity environments are more often affected bythese diseases. Elemental sulfur or copper canbe used to protect the flag leaf prior to infection

Further Resources

Several websites offer forecasts for small grain

disease incidence:

MoreCropis a website that predicts incidence

of small grain diseases in the Pacific Northwest.http://pnw-ag.wsu.edu/MoreCrop

North Dakota State University Small Grain

Disease Forecasting Model www.ag.ndsu.nodak.edu/cropdisease

Tan Spot and Septoriaan spot and septoria are fungal leaf diseasesthat are widespread in wheat, but are not as seri-ous as other diseases. Tese fungal pathogenssurvive on the infected residue of a previous

wheat crop. In the spring, the funga l fruitingbodies will produce spores that infect the newlyplanted seedlings, thus perpetuating the diseasecycle. Incorporating infected plant residue willreduce the spread of these diseases.

Fungal leafspots affect grainyield by reducing the photosyn-thetic area of the plant, and areconsidered the common coldof small grains. In arid regionsthese diseases do not signifi-cantly decrease yield. And whilethey can decrease test weight,

which may lower the price tothe producer, they do not reduce

end-use baking quality. Organic farmers maychoose simply to live with these diseases and theaccompanying yield loss, a decision that doesnot require further management (Grey, 2009).

Further Resources

Fungal Leaf Spot Diseases of Wheat: Tan spot,

Stagonospora nodorumblotch and Septoria

triticiblotch.NDSU Extension circular PP-1249.

2009. M. McMullen and T. Adhikari.www.ag.ndsu.edu/pubs/plantsci/pests/pp1249w.

htm

BlotchTe blotch diseases are fungal leaf diseases sim-ilar to an Spot and Septoria, but they affectonly barley. Tere are three blotch diseases tobe aware of: Net Blotch, Spot Blotch, and theSpot Form of Net Blotch. emperatures of 68to 77F and 100% relative humidity are idealfor spore production (Schwartz et al., 2009a).

Tan spot on wheat.Photo: Dr. Mary Burrows,

Montana State Univer-

sity, www.bugwood.org
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Organic management practices for prevention ofthese diseases:

Plant varieties adapted to your geo-graphic area.

Use crop rotation.

Plant into a firm, mellow seedbed.(Loose seedbeds promote disease.)

Control weeds in summer-fallow land.(Weeds deplete soil moisture, and thatpredisposes plant roots to infection inthe fall.)

Always plant good-quality seed. (Bin-run seed is higher risk.)

Plant at the recommended date for yourgeographic area. (Early planting orextended, warm fall weather promotesdisease.)(Watkins and Burrows, 2009)

Fusarium Head BlightFusarium head blight (FHB), also known as scab,is a fungal disease that survives on the residue ofwheat, barley, and corn. For this reason, rotationto a broadleaf crop can reduce the fungal inocu-lum and help to ensure it does not affect a sub-sequent crop. If FHB is a problem in your area,avoid planting adjacent to a field with wheat, bar-ley, or corn residue (McMullen et al., 2008b).

A key diagnostic symptom of FHB is partia lbleaching of the head, producing small, pow-

dery white kernels cal led tombstones. If you findthese kernels in harvested grain, or suspect youhave FHB, make sure you have the grain testedfor deoxynivalenol (DON). If the test resultis above the threshold of 1 ppm, do not sellthe grain for human consumption.Grain thattests above 5 ppm is not recommended as feedfor non-ruminants or pregnant cows. FHB pro-duces the DON vomitoxin, and it can cause ill-ness if consumed.

Recent efforts by public and private breeding

programs in variety development have proveneffective in management of FHB in wheat (Bur-rows and Grey, 2008). Varieties with moderateresistance can limit crop failure. However, noresistance is available in barley varieties.

or an anticipated rain, and as a last-ditch effortto reduce the impact of rust. However, surfaceprotectants require multiple applications to beeffective. Use of elemental sulfur in a wettablepowder form is recommended. Elemental sulfurcan also reduce powdery mildew (Grey, 2009).

Damping Off

Damping off can be caused by many differentfungal pathogens that live in the soil. Teseinclude Pythium, Fusarium, and Rhizoctonia.Damping off causes seedling death and resultsin bare patches in the field. Wet, cool soil oftenprovides ideal conditions for the developmentof damping-off pathogens. Delayed plantingcan help to avoid this situation (Schwartz etal., 2009b). Cultural controls for damping off:Plant high quality seed in a firm, well-preparedseedbed at optimum pH, soil temperature, andfertility level for rapid germination and growth.

Avoid compaction, poorly drained fields, andexcess irrigation that can favor damping-offpathogens (Schwartz et al., 2009b).

Rhizoctonia is often associated with continuouscereal production in no-till systems. Because till-age breaks up the underground fungal growth,this pathogen is not expected to be a problemin an organic system if crop rotation and laterplanting dates are used to allow the soil to warmbefore planting (Burrows, 2010).

Te beneficial bacteria Bacillus subtilisis a bio-logical agent registered for control of Fusarium,Pythium, and Rhizoctonia. Bacillus subtilisissold under the trade name of Kodiak and isapproved for organic crop production (Schwartzet al., 2009b). Kodiak is applied as a seed treat-ment prior to planting. As with any input,always check with your organic certifier priorto application to ensure approval. For Kodiaklabel information, see the ARA EcologicalPest Management Database at www.attra.ncat.org/attra-pub/biorationals.

Fungal Root DiseasesCommon fungal root diseases of small grainsinclude Fusarium crown rot, common root rot,and take-all. While resistant varieties are availablefor Fusarium and common root rot, no wheator barley varieties are resistant to take-all. Oats,corn, and broadleaf plants are resistant to take-all, however (Van Voast, 2009).

Further Resources

The Wheat Fusarium Head Blight Prediction Centeris a joint effort of

several universities to predict the incidence of Fusarium head blight.www.wheatscab.psu.edu/index.html
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Deep-plow fields that have a severeergot infestation to bury the sclerotia.Te ergot sclerotia are less likely to sur-vive if buried more than 1 inch deep.

Plant only ergot-free seed or Certifiedseed to avoid introducing or re-intro-ducing the fungus into the crop.

Eradicate or prevent wild grasses from

setting seed in fields, rocklands, head-lands, ditches, and fence rows. Mow

wild and escaped grasses and pastures,or graze pastures before they flower, toprevent ergot infections.

Resistant commercial varieties of wheat,barley, rye, and cultivated grasses arenot available. However, some resistancedifferences among varieties may occur,and those with long flowering peri-ods may be more frequently infected.Generally, grain crops that experiencea long, cool period during floweringare highly susceptible. Avoid irriga-tion prior to and during the floweringperiod of grasses (McMullen and Stol-tenow, 2002; Burrows, 2010).

Steve Zwinger at the North Dakota State Uni-versity Experiment Station in Carringtonreports they do have some minimal ergot intheir organic grains. However, it has not been aproblem for them and has always been under theallowed tolerances.

Further Resources

For more information on ergot, including its role

in history, see The American Phytopathological

Society website.

www.apsnet.org/education/lessonsPlantPath/

ergot/default.htm

Smut and BuntSpecial thanks to Dr. Blair Goates, a smut andbunt expert at the USDA-ARS facility in Aberdeen,

Idaho, for sharing information for this section.Smuts and bunts are both soil-borne and seed-borne fungi that can severely damage yields.hese diseases are of particular concern fororganic grain farmers in the United States, sincevery few varieties have been bred with resistance.However, there are excellent dwarf bunt-resistantvarieties available that are adapted to the winter

wheat dryland farming areas of southern Idaho

ErgotWith the revival of cereal rye in organic systemsas both a cash grain and a cover crop, ergot maybecome a greater problem. Ergot is a fungal dis-ease that infects the flowers of cereal crops andproduces ergot sclerotia in the heads. Te ergotbody becomes a contaminant of the harvestedgrain and spreads to new fields in seed. While

the crop yield reduction can be from 5 to 10%,the main concern with ergot is the danger itposes to human and livestock health. Te ergotfungus produces mycotoxins that cause miscar-riage, convulsions, and in extreme cases, death.

Note:If you are growing cereal rye anywhere

in your rotation, it is important that you have

a clear, written contract with your buyer that

documents their standards for ergot. If ergot isdetected, some buyers may refuse to take the

grain or severely dock the price. Make sure you

understand your buyers standards before plant-

ing this crop.

Because rye is an open-pollinated crop, it ismore susceptible to ergot infection. However,triticale, wheat, durum, barley, oat, quackgrass, crested wheat grass, brome grass, foxtail,rye grass, orchard grass, timothy, wild rye, andother grasses serve as ergot hosts (McMullenand Stoltenow, 2002).

Dr. Mary Burrows of Montana State Universitynotes that ergot can also be a problem in grassy

hay crops. One Montana farmer had a field inalfalfa for seven years, and then planted a cropof hay barley that experienced a significant ergotinfestation.

Grain crops are susceptible to ergot infectionat the flowering stage. Cool, wet weather thatlengthens flowering will increase the possibilityof an infection. Te honeydew that forms onthe heads contains spores of the fungus. Tisattracts insects that further spread the sporesamong the grain flowers.

o minimize ergot infestations, there are severaltechniques organic farmers can use.

Rotate cereals and grasses with non-susceptible crops for one year or longer.Te ergot sclerotia, or dark bodies, cansurvive in the soil for more than threeyears. hereafter, summer fallow orcrop rotation to a non-cereal crop for atleast one year will help reduce ergot.
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and then dry before planting. Or, wash with adilute solution of bleach in hot water for evengreater efficacy. ake care with any heat treat-ment of seed because excessive temperatures cankill the seed and decrease the germination rate.

In 1888, the Danish seedsman J.L Jensen pro-posed the following standards for hot watertreatment of seeds. Basically, this process

involved soaking the seed for 110 minutes inwater held at 118.4F (48C), or 95 minutes at120.2F (49C) (Mathre et al., 2006).

rial and error may be needed if using the hot-water-wash method, as no recent standards areavailable for grains. Run a test batch of 100 ker-nels in various treatments and then test the ger-mination of the seeds after the treatment.

While not specific to grain seeds, guidelines for

using hot water wash for vegetable seeds are

available from Ohio State University Extension,

Hot Water and Chlorine Treatment of Vegeta-ble Seeds to Eradicate Bacterial Plant Patho-

gens, Miller and Ivey, HYG-3085-05, http://ohio

line.osu.edu/hyg-fact/3000/3085.html

Internal Spores

In the second group of smut and bunt dis-eases, the fungi are carried within the seed asdormant hyphae and not as spores on the seedsurface. Te most common disease in this cat-egory is loose smut of wheat and barley. Spores

of these fungi infect the grain kernel at flower-ing. Te fungus then moves into the embryo ofthe seed, and the infected seed cannot be distin-guished from a healthy seed prior to planting.After planting, the fungus resumes its life cycleand maintains itself in the growing point of theplant, eventually infecting the developing grainhead and converting it to a mass of spores (Cookand Veseth, 1991). For this type of disease, thereare few organic options. Since the disease isinside the seed coat, an external treatment suchas washing is ineffective.

Te consolation is that this dis-ease will not destroy an entirecrop. A 15% yield loss wouldbe considered unusually highfor this disease, with 1% to2% yield loss more common.Likewise, loose smut has littleimpact on end-use quality. Ifthis disease appears, however,

and northern Utah, and also a few soft whitewheat varieties adapted to the Palouse region.Te introduction of conventional seed-treat-ment fungicides has made the development ofresistant varieties a low priority in breeding pro-grams in the United States. In contrast, Canadaand Europe both still breed some grain varietieswith tolerance to these diseases.

External SporesTe smut and bunt diseases can basically be bro-ken into two groups. In the first group, fungalspores occur on the exterior of the seed coat.Tis group includes common bunt of wheat,covered smut in barley, and loose smut in oats.Tese spores on the coating of the grain infectthe plant after seeding but before emergence.Tese diseases can be quite serious: commonbunt can wipe out 60% to 70% of a crop.

However, because these spores are on the exte-rior of the seed, some organic treatments showpromise. Organic producers in Europe have hadsuccess with a product called illecur. Tis isa commercially available treatment based on aformulation of mustard powder. Likewise, large-scale equipment used to treat seed with steam

jets is also used in Europe. As of this writing(2010), no such treatment is available in theUnited States.

A beneficial fungus, Muscodor albus, has shownsome promise in research trials. M. albusis anendophytic fungus first isolated and describedfrom the non-native cinnamon tree (Cinnamo-mum zeylanicum) in Honduras by Gary Stro-bel at Montana State University (BiocontrolNews and Information, 2008). When used as afumigant, this fungus kills common bunt spores(Goates and Mercier, 2009). As of this writing,however, there is no commercial source of thisproduct for seed treatments.

Te beneficial bacteria Bacillus subtilisis a pos-sible organic seed treatment for these diseases.

Bacillus subtiliscan be used to control storagefungi such as PenicilliumandAspergillus(Grey,2009). Bacillus subtilisis sold under the tradename Kodiak and is approved for organic cropproduction. For Kodiak label information, seethe ARA Biorationals database at www.attra.ncat.org/attra-pub/biorationals.

For producers with small amounts of seed, wash-ing may be an option. Wash seed in hot water

Loose Smut on wheat.

Photo: Donald Groth,

Louisiana State Univer-

sity AgCenter, www.bug-

wood.org
http://ohioline.osu.edu/hyg-fact/3000/3085.htmlhttp://ohioline.osu.edu/hyg-fact/3000/3085.htmlhttp://ohioline.osu.edu/hyg-fact/3000/3085.htmlhttp://ohioline.osu.edu/hyg-fact/3000/3085.htmlhttp://www.attra.ncat.org/attra-pub/biorationalshttp://www.attra.ncat.org/attra-pub/biorationalshttp://www.attra.ncat.org/attra-pub/biorationalshttp://www.bugwood.org/http://www.bugwood.org/http://www.bugwood.org/http://www.attra.ncat.org/attra-pub/biorationalshttp://ohioline.osu.edu/hyg-fact/3000/3085.html


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BYDV is not a major concern in winter wheatsince that crop is planted after a frost, whichsignificantly reduces aphid populations. If try-ing to manage for BYDV in winter wheat, makesure to delay planting until cool fall nightsarrive, generally after Labor Day, since aphidshave little cold tolerance (Grey, 2009). Likewise,the northern states have a lesser problem withBYDV in spring-seeded wheat and barley since

both crops are advanced in their growth stagesbefore aphids migrate north.

Further Resources

For more information on management of Barley

yellow dwarf virus, see:

Washington State University Bulletin

http://pnw-ag.wsu.edu/smallgrains/barley%20

yellow%20dwarf.html

PennState Field Crop Disease Facts

http://extension.psu.edu/small-grains/documents/

barley-yellow-dwarf.pdf

American Phytopathological Society

www.apsnet.org/edcenter/intropp/lessons/viruses/

Pages/BarleyYelDwarf.aspx

Wheat Streak Mosaic Virus

Another serious viral disease is wheat streakmosaic, which is transmitted by the wheat curlmite, a tiny insect that is barely visible with theuse of a hand lens. Tis disease is a bigger prob-

lem for the northern states than Barley yellowdwarf (McMullen, 2002). While wheat is theprimary target of the mite, it will also feed oncorn, barley, oats, and various native and weedygrasses. o date, there is no evidence that themite transmits the virus to rye.

A main organic management strategy to breakthe life cycle of the wheat curl mite is to elimi-nate any green bridges near your grain fields.Green plant material serves as a host for the miteand the virus. While grassy weeds can serve thisfunction, the real reservoir comes from in-fieldvolunteer grains. illage will eliminate this threat.A long period of brown out in August, with novolunteer grain or early-seeded wheat, will reducemite populations. For this reason, make sure thatwinter wheat seeding is late enough to discouragehosting the mite (McMullen, 2002).

Providing habitat for mite predators such as spi-ders and carabid beetles can also help preventspread of the disease. Create a mulch of plant

it is important that an organic farmer not saveseed, but purchase seed from disease-free fieldsfor the following crop year. Because loose smutis carried within the seed, identification of infec-tion can be determined only by laboratory analy-sis. Even [c]ertified seed is not guaranteed to befree of loose smut or other seed borne diseases(Lipps, no date).

Smuts and bunts can cause severe crop loss.While some grain varieties in the United States

have limited resistance to these diseases, this

is due mainly to their flowering habit and less

to breeding efforts. Organic seed treatments

options are few, with field sanitation and crop

rotation being the best practices to prevent

infection. More research is needed in the area

of successful organic small grain seed treatments

for prevention of these diseases.

Further ResourcesOrganic Seed Treatments and Coatings. 2010.

E. Gatch. www.extension.org/article/18952

Organic Seed-treatment as a Substitute for

Chemical Seed-treatment to Control Com-

mon Bunt of Wheat. 2000. M. El-Naimi, H. Tou-

bia-Rahme, and O. F. Mamluk. European Journal

of Plant Pathology. 106:433-437.

Viral Diseases

Barley Yellow Dwarf VirusSeveral grain diseases are viral and are car-ried by insects such as aphids and mites. Oneof these viral diseases is barley yellow dwarf(BYD), caused by Barley yellow dwarf virus(BYDV). Barley yellow dwarf is a misleadingname, because it also can infect wheat, oats,rye, corn, sorghum, and more than 100 speciesof grasses (Montana State University Extension,1998). BYDV is spread by more than 20 spe-cies of aphids. Te aphids ingest the virus whenfeeding on infected plants and transmit the dis-

ease to subsequent plants while feeding on them(Wegulo, 2008).

Varieties resistant to BYDV are available. BYDVis most active in Washington, Oregon, and Idaho.In this region, it is crucial that organic growersplant barley varieties with resistance to BYDV.

Some Great Plains breeding programs havedeveloped plant resistance in certain variet-ies. However, in Montana and North Dakota,

Barley Yellow Dwarf

Virus. Photo: Keith

Weller, USDA-ARS, www.

bugwood.org
http://pnw-ag.wsu.edu/smallgrains/barley%20yellow%20dwarf.htmlhttp://pnw-ag.wsu.edu/smallgrains/barley%20yellow%20dwarf.htmlhttp://extension.psu.edu/small-grains/documents/barley-yellow-dwarf.pdfhttp://extension.psu.edu/small-grains/documents/barley-yellow-dwarf.pdfhttp://www.apsnet.org/edcenter/intropp/lessons/viruses/Pages/BarleyYelDwarf.aspxhttp://www.apsnet.org/edcenter/intropp/lessons/viruses/Pages/BarleyYelDwarf.aspxhttp://www.apsnet.org/edcenter/intropp/lessons/viruses/Pages/BarleyYelDwarf.aspxhttp://extension.psu.edu/small-grains/documents/barley-yellow-dwarf.pdfhttp://pnw-ag.wsu.edu/smallgrains/barley%20yellow%20dwarf.html


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Figure 2. Organic InsectControl Hierarchy.

varieties. Solid-stem varieties work the best, andlocal experiment stations should have records ofvarieties with the greatest resistance. However,these solid-stem varieties are primarily semi-dwarf, and semi-dwarf varieties may not be ascompetitive with weeds in an organic system. Afarmer will need to select a variety based on hisor her primary pest problem. If a diverse rota-tion is in place and wheat stem sawfly pressureis minimal, it may be more important to selecta variety with quick, early growth to suppressweeds, rather than selecting a semi-dwarf varietywith wheat stem sawfly resistance.

Diverse crop rotationcan also help to break theinsect cycle. Organic farmers tend to have fewersawfly problems in general because of their croprotation practices and the biodiversity inherentin organic production systems. Rotation to aless-preferred crop may also help to break thelife cycle of cutworms and wireworms. Organicfarmers also can benefit from surroundingmonocultures that lure the key pests away. On

the other hand, a neighboring monoculture mayalso be the source for recurrence of an insectpest problem.

o usetrap crops, plant something on the bor-der of your grain field that bugs like to eat andthat stays green longer than the crop for harvest.

After attracting the bugs into the trap crop, tillit into the ground. Most bugs will not survivetillage. Tis practice can work well to manageedge-effect pests like the wheat stem sawfly that

residue, such as a strip of mowed grass around thegrain field, to create a habitat for these beneficials.

Further Resources on Spider Predation

Spider predation in agroecosystems: Can

spiders effectively control pest populations?

2003. D. Maloney, F.A. Drummond, and R. Alford.

University of Maine. Technical Bulletin 190.www.umaine.edu/mafes/elec_pubs/techbulletins/

tb190.pdf

Further Resources

High Plains IPMwebsite

http://wiki.bugwood.org/HPIPM:Main_Page

American Phytopathological Societywww.apsnet.org

Compendium of Wheat Diseases and Pests,

Third Edition.2010. APS Press.

Wheat Health Management.R.J. Cook and R.J.

Veseth. 1991. APS Press.

North Carolina Organic Grain Project, Wheat

and Small Grain Disease Management

www.organicgrains.ncsu.edu/pestmanagement/

wheatdiseases.htm

Resource Guide for Organic Insect and Dis-

ease Management, Cornell University.

http://web.pppmb.cals.cornell.edu/resourceguide/

index.php

In-crop InsectsManagement of insects within a growing cropcan be a challenge since bugs can move fromone spot to the next. However, there are somestrategies to minimize in-crop insect damage.Similar to organic weed and disease manage-ment, organic insect management is based onthe National Organic Program guidelines forpest management, section 205.206. Te foun-dational principles of cultural practices, rota-tion, and sanitation come first. Next are the sec-ond-tier strategies of predators, traps, and lures.

And finally, biological and allowed syntheticsubstances can be used, provided the first twosteps in the hierarchy are in place.

Cultural PracticesAs with other organic pest-control strategies,prevention is more effective than cure. Resistantvarietiescan often help manage problem insects.For example, farmers are now able to reduce

wheat stem sawfly damage by selecting resistant

205.206 (a)

Crop RotationSanitation

Cultural Practices

205.206 (e)

Biological substance,or synthetic included on

the National List

Level 1

205.206 (d)

Management practices which suppressthe spread of disease organisms; or

application of nonsynthetic biological,botanical, or mineral inputs

Level 2

Level 3
http://www.umaine.edu/mafes/elec_pubs/techbulletins/tb190.pdfhttp://www.umaine.edu/mafes/elec_pubs/techbulletins/tb190.pdfhttp://www.organicgrains.ncsu.edu/pestmanagement/wheatdiseases.htmlhttp://www.organicgrains.ncsu.edu/pestmanagement/wheatdiseases.htmlhttp://web.pppmb.cals.cornell.edu/resourceguide/index.phphttp://web.pppmb.cals.cornell.edu/resourceguide/index.phphttp://web.pppmb.cals.cornell.edu/resourceguide/index.phphttp://www.organicgrains.ncsu.edu/pestmanagement/wheatdiseases.htmlhttp://www.umaine.edu/mafes/elec_pubs/techbulletins/tb190.pdf


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protection and shelter, and also allow for easymovement to different parts of a field.

Russian Wheat AphidAnother major in-crop insect pest for smallgrains is the Russian wheat aphid (RWA). TeRussian wheat aphid affects grain by injecting atoxin that damages the plant, typically resulting

in a white stripe running down the leaf blade.Several resistant varieties have been developedand are used extensively in Colorado, Kansas,and exas, where warm temperatures allow forgreater RWA survival. Most grain in Montanaand North Dakota does not have this resis-tance. Tese states escape serious aphid infesta-tion because their cold northern climates delayaphid migration, although climate change mayaffect this. University of California IPM PestManagement Guidelines point out, Wheat andbarley are the most susceptible; rye and triticale,

while susceptible, are usually less damaged; andoats appear to sustain little or no injury. Rus-sian wheat aphid does not attack corn, sorghum,or rice (Summers et al., 2009). A diverse croprotation can help minimize Russian wheat aphiddamage across an entire farm.

Another management strategy for this pest isto control volunteer wheat and barley. Accord-ing to the HighPlains IPM website, Volunteersare the most important source of infestation forthe new crop in the fall. ry to have a three-

week volunteer-free period prior to emergence offall seedlings. Winter grains should be plantedas late as possible in Colorado, Nebraska, and

Wyoming. Spring grains should be planted asearly as possible (Peairs et al., 2010).

In addition, a healthy, stress-free crop is morelikely to survive an aphid infestation. Make surethe fields nutrient levels are sufficient to producea healthy stand (Peairs et al., 2010).

clearly prefer certain cultivars over others. Localexperiment stations will be able to provide infor-mation on varieties and preferences of this pest(Morrill et a l., 2002).

Specific In-crop Insect Pests

Grasshoppers

One of the oldest insect pests of grain crops isthe grasshopper. Tis insect can be difficult tocontrol with organic methods, because it canmove from a control area to a non-control areaand vice-versa. Tere has been some limited suc-cess with the use of Nosema locustae, a parasiticfungus that is combined with wheat bran bait forfield use. Often, the results of Nosema are seenover several years of use, with mixed results whenused on large areas (Cunningham and Sampson,1996). Several brand names of Nosema are avail-able and information about them can be found

in the ARA Biorationals database (www.attra.ncat.org/attra-pub/biorationals).

Pest scouting is an essential part of usingNosema successfully. Te most effective time touse it is when the grasshoppers are young (thirdinstar stage). Usually, when you notice a largeinfestation, it is too late to use biological con-trols. Make sure you are watching for grasshop-pers before they become a problem.

Mowing around grain fields may also help controlgrasshoppers. Te shorter plants limit their foodsupply and make them more vulnerable to preda-tors. Te larger the field, the wider the mowedstrip will need to be (Planet Natural, 2009).

Chickens are voracious grasshopper eaters, andon smaller acreages chickens may be an effectivemeans of grasshopper control. However, chick-ens do require adequate water, housing, and pro-tection from predators. Mobile chicken coops,sometimes called chicken tractors, provide

Further Resources

CARMAstands for Case-based Range Management Advisor. It is a com-

puter-based tool to help assess the economics of managing grasshopper

infestations in rangeland. www.sidney.ars.usda.gov/grasshopper/Support/

Carma.htm

USDA-APHIS Plant Protection and Quarantineoffers several resources

for grasshopper management, including an IPM handbook and an annual

grasshopper hazard map for the western United States. www.aphis.usda.

gov/plant_health/plant_pest_info/grasshopper/index.shtml

Russian Wheat Aphid. Photo: Frank Peairs, Colorado

State University, www.bugwood.org
http://www.sidney.ars.usda.gov/grasshopper/Support/Carma.htmhttp://www.sidney.ars.usda.gov/grasshopper/Support/Carma.htmhttp://www.sidney.ars.usda.gov/grasshopper/Support/Carma.htmhttp://www.aphis.usda.gov/plant_health/plant_pest_info/grasshopper/index.shtmlhttp://www.aphis.usda.gov/plant_health/plant_pest_info/grasshopper/index.shtmlhttp://www.aphis.usda.gov/plant_health/plant_pest_info/grasshopper/index.shtmlhttp://www.aphis.usda.gov/plant_health/plant_pest_info/grasshopper/index.shtmlhttp://www.sidney.ars.usda.gov/grasshopper/Support/Carma.htm


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et al., 2005). Sheep and goats were turned intosummer fallow fields and consumed the saw-fly larvae that live in the grain stubble. Consultwith a livestock specialist for stocking rates anddates if considering this technique.

Stored-grain InsectsInsects are not only a problem while the crop is

growing; they are also a concern during grainstorage. Te most common grain-storage insectsare secondary insects that attack cracked andbroken kernels in the grain bin, or kernels thatare in poor condition or otherwise damaged(Canadian Grain Commission, 2009). Tesesecondary pests include the rusty grain beetle,the hairy fungus beetle, the red flour beetle, andthe foreign grain beetle.

Te most damaging storage pests are insects thatcan chew directly into the grain. In the North-

ern Great Plains, these include the lesser grainborer and the rice and maize weevils. Of all ofthese pests, the only one that regularly overwin-ters in the North is the rusty grain beetle.

Further Resources

Stored Grain Pest Management.2002. P. Sul-

livan. ATTRA.

www.attra.ncat.org/attra-pub/storedgrain.html

Storage Temperature

Special thanks to Dr. Paul Flinn, USDA-ARSCenter for Grain and Animal Health Research,Manhattan, Kansas, for providing much of theinformation on storage temperature, sanitation,and beneficial insects.

Te best technique for controlling insect pests isto control the storage temperature of the grain.Te cooler the temperature, the less active theinsects and the less likely they are to reproduce.Insect activity as it relates to temperature isgiven in the following table.

Wheat Stem SawflyTe wheat stem sawfly has been a major in-croppest in the Northern Great Plains since the early1900s. Since then, various species of this insecthave become a worldwide problem. Te femalesawfly lays one to two eggs per plant stem andcan lay as many as 30 to 50 eggs in a season.

After the eggs hatch, the larvae live inside the

plant, causing damage by trapping nutrients andpreventing grain heads from gaining weight.

Plant breeders have introduced solid-stemmedwheat varieties. While this has reduced the saw-fly problem, it hasnt solved it completely. Eventhe most solid varieties can still experience somesawfly damage.

Dr. David Weaver, professor of entomologyat Montana State University, gives the follow-ing principles for non-chemical management ofwheat stem sawfly (2011):

Leave the grain stalks as high as pos-sible during harvest. Ideally, leave 1/3of the stem height. Tis will conservethe naturally occurring Braconid para-sitoid wasps that provide a control forthe sawfly.

Grow trap crops to protect hollow-stemspring wheat varieties. Winter wheator a solid-stem spring wheat will work.Plant the trap crop between last yearswheat crop, which will be the source of

new insects, and this years wheat crop.

Use a forage winter wheat variety as atrap crop. Hay the crop at the end ofthe sawfly flight period.

Plant the most-solid-stem varieties.Check with a local Extension agent forthis information.

Include spring wheat crops in the rota-tion to increase parasitoid numbers.

Grow non-host cereals or other alter-

nate crops. Oats and smooth brome areexamples of alternate non-host crops forsawfly. Sawfly cannot survive in oats,making it an excellent choice for croprotation.

Integrating livestock into the system could pro-vide an acceptable level of sawfly control. Dr. PatHatfield, livestock specialist at Montana StateUniversity, has achieved good sawfly controlby using sheep to graze wheat stubble (Goosey

Table 1. Insect Activity at Various Temperature Ranges.

Temperature Insect Activity

86F (30C) Optimal temperature for insect activity

77F (25C) Reproductive rate is cut in half

68F (20C) Insects stop developing

50 59F ( 10 15C) Activity stops

(Flinn, 2009)


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if the grain is carefully monitored for changesin temperature and insect numbers. Farmers in

warmer states such as Kansas and Oklahomausually store grain over only one winter to avoidinsect and mold problems. Tis issue of stor-age time affects a farmers marketing plan, sincesome specialty organic grains can take morethan a year after harvest to sell.

Further Resources

Questions and Answers about Aeration Con-

trollers. Kansas State University Extension bul-

letin. www.ksre.ksu.edu/library/grsci2/mf2090.pdf

SanitationWhen placing organic grain in bins, make surethey have been thoroughly cleaned and that allcracks have been sealed. Also, never put newgrain on top of old grain. Use smaller bins toreduce the risk of spreading insect or mold prob-lems. Te standard 3,000- to 5,000-bushel binsshould be small enough, but avoid using thelarge 50,000-bushel bins. Air does not circulate

well in these bins, and small infestations soonbecome very large problems. One infestationcan ruin an entire crop if its all in the same bin.

Beneficial InsectsIn one research study, Hymenoptera waspsproved successful predators of the lesser grainborer and functioned well at the cooler temper-

atures so important to slow the activity of thepest insects (Flinn, 1998). In fact, these bene-ficial wasps provided a very high level of borersuppression (99%) at 25C.

Bear in mind that some of these parasitic waspsoccur naturally in stored grain. Any organicinsecticide meant to control pests, such as dia-tomaceous earth, will also kill the beneficial

Cooling grain to below 68F (20C) minimizesinsect activity. Te usual way to do this is torun fans at night when the outside air is cool-est. Install a thermostat on the fan, so that itdoes not operate in the daytime and circulatehotter air into the bin. Set the fan thermostat

to 77F (25C). When the outdoor temperaturedrops to this level at night, the fan will start andthe grain will begin to cool. It may take several

weeks to cool the grain to 77F. Ten in Sep-tember, cool the grain down to 68F (20C)as the nights cool off even more. Finally, coolthe grain down to 59F (15C) and let it staythere the rest of the time its in storage. It is veryimportant to cool grain down as soon as pos-sible so that the insects have less time to developunder warm, favorable conditions. Tese specifictemperature points can vary in a colder environ-

ment that has later harvests, but the conceptremains the same.

Some farmers do not use fans during a rain, fear-ing that this would increase humidity in thebins. However, as cool outside air is warmedby the grain, the relative humidity of the airdecreases. Running the cooling fans during arain event will not increase humidity in the bin ifthe outside temperature is less than 77F (25C).

Likewise, some farmers worry that running fanswill dry out the grain and thus decrease its test

weight. Tis is only a concern if the fans runboth day and night and pull in high-temperaturedaytime air. If the fans run only when the airtemperature is less than 77F, loss of test weight(grain moisture) should not be a problem.

How long grain can be stored will depend onthe location. In colder states such as Montanaand North Dakota, grain can be stored for twoto three years with no insect or mold problems

A parasitoid wasp for storage insects (Anisopteroma-

lus Calandre). Photo: Dr. Paul Flinn, USDA-ARS

Grain bins. Photo: Susan

Tallman, NCAT


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DE may affect grain quality by decreasing thetest weight. Also, it slows down the flow of grainin handling systems. It is easily digestible byhumans and will not affect the end-use qualityof the grain for baking purposes. In a lab analy-sis of flour, DE would show up as ash content.

Te particle size of DE is similar to talcum pow-der. ake care when using it, and wear a respira-

tor to limit inhalation. DE does disperse in han-dling and can be blown out of the grain when itis loaded from the bin, if desired.

Tere are two recommended ways to use DE instorage: the incorporation method and the sand-wich method.

Incorporation MethodOf the two methods, incorporation is mosteffective. o use this method, mix DE into theentire bulk of the grain stored. Tis may not be

necessary, or desirable, if the expected insectpressure does not warrant such heavy use.

Te best way to mix in the DE is to apply a layeron top of the grain in the truck, prior to load-ing in the bin. Cut it in with a shovel beforeunloading, then auger the grain into the bin.Mix in the exact recommended amount of DEfor the number of bushels in the truck. o deter-mine the rate of application, check the listing onthe packaging.

Another alternative is to stand at the auger andthrow in a bit of DE every so often. Tis is lessaccurate and can lead to patchy application,especially if the person doing the job becomesdistracted.

Sandwich MethodTe sandwich method can cut costs and willaffect the test weight less than the incorporationmethod. In this method, add DE to the firstload of grain into the bin at the recommendedrate. For the middle loads, do not add any DE.

For the last two loads, add DE again at the rec-ommended rate. Ten add 6 inches of DE at thetop of the bin.

DE can also be used in an empty bin to get ridof residual bugs. Use the bin dryer to blow itaround. Or use a special applicator to apply DEdirectly to the bin surface.

wasps. However, aeration to cool the grain willnot kill the parasitic wasps but will help them tocontrol the pests more effectively. A farmer must

weigh the pros and cons of using controls, andestablish a threshold tolerance for pests.

Further Resources

As of this writing, very few companies in the

United States produce beneficial insects for stored

grain insect control. One is Biofac Crop CareinMathis, Texas. Contact them at their website www.

biofac.com, or toll-free at 1-800-233-4914.

Diatomaceous EarthSpecial thanks to Dr. David Weaver, MontanaState University, for providing information onDiatomaceous earth.

Diatomaceous earth (DE) can be used to controlstorage insects. DE works by clinging to insects

and adsorbing their protective surface-wax,allowing moisture to escape, and drying themto death. It works better at higher temperaturesbecause then insects are more active. DE may bea good option in warmer regions, where coolernights do not arrive until several weeks afterharvest. DE also works better in dry conditions,since it loses activity when it contacts water. Astate with a hot, dry climate, such as Arizona,might be an ideal place to use DE.

DE is made of fossilized marine diatoms and iscomposed primarily of silicon dioxide with somecalcium. Tere are different kinds of DEfresh-

water and saltwaterwith different characteris-tics. For a complete listing of various trade namesof DE, check the ARA Biorationals databaseat www.attra.ncat.org/attra-pub/biorationals/.

Use Certified Organic DE

When using DE, be aware that not all products

are certified for organic use. Some DE prod-

ucts may contain fillers or additives that are not

allowed under organic standards. Make sure you

document which DE product you use, and verify

that it is allowed in organic production. Contact

your certifier if you have any questions.

Te activity of DE varies with insect species.It doesnt work very well on the red flour bee-tle, but other insects are quite vulnerable to it.Experts are not sure why the effectiveness differsby insect species.


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ReferencesBhadriraju, Dr. Subramanyam. Kansas StateUniversity. 2009. Personal conversation.

Biocontrol News and Information. 2008.Endophyte Spices up Biofumigation. Vol. 28.No. 4. p. 69N 74N.

Burrows, Dr. Mary. Montana State University.

2009. Personal communication.Burrows, M. and R. Grey. 2008. Fusar-ium Head Blight (scab) of Wheat and Bar-ley. Montana State University. MontGuideM200806AG. http://msuextension.org/publications/AgandNaturalResources/MT200806AG.pdf

Canadian Grain Commission. 2009. Second-ary Insect Pests. www.grainscanada.gc.ca/storage-entrepose/sip-irs/sip-irs-eng.htm

Cook, R.J. and R.J. Veseth. 1991. WheatHealth Management. Te American Phyto-pathological Society. p. 57.

Cunningham, G. and M. Sampson. 1996.Grasshopper Integrated Pest Management UserHandbook. USDA-APHIS echnical Bulle-tin 1809. www.sidney.ars.usda.gov/grasshopper/Handbook/index.htm

Flinn, Dr. Paul. USDA-ARS. 2009. Personalconversation.

Flinn, P.W. 1998. emperature Effects onEfficacy of Choetospila elegans (Hymenop-tera: Pteromalidae) to Suppress Rhyzoperthadominica(Coleoptera: Bostrichidae) in StoredWheat. Journal of Economic Entomology. Vol.91, No. 1. p. 320-323.

Goates, B. and J. Mercier. 2009. Effect of bio-fumigation with volatiles from Muscador albuson the viability of ilettia spp. teliospores.Canadian Journal of Microbiology. Vol. 55. p.203-206.

Goosey, H.B., P.G. Hatfield, A.W. Lenssen, S.L. Blodgett, and R.W. Kott. 2005. Te Poten-tial Role of Sheep in Dryland Grain ProductionSystems. Agriculture, Ecosystems and Environ-ment 111 (2005) 349353. http://ddr.nal.usda.gov/bitstream/10113/35682/1/IND43759248.pdf

Grey, Dr. Bill. Montana State University. 2009.Personal communication.

SpinosadA final product that has gained some interest forgrain storage is spinosad. One formulation ofspinosad is the by-product of bacterial fermen-tation and is allowed for use in organic systems.It has proven effective in managing insects instored grain (Bhadriraju, 2009). As of this writ-ing, however, Spinosad is not labeled in the

United States to control stored grain pests, assome countries will not accept spinosad-treatedgrain under international Codex tolerances. Temanufacturer is waiting for trade negotiationsto be completed before labeling the product asacceptable for use on stored grain.

Te 2010 Organic Materials Review Institute(OMRI) Generic Materials List shows spinosadis an allowed nonsynthetic with restrictions. Itcan be used as a pest lure, repellent, or trap, andas an insecticide if the criteria of the pest man-agement rule are met. Since there is some grayarea on the of use of spinosad in stored grain,it is best to check with your organic certifierbefore using.

However, spinosad is accepted to treat in-cropinsect pests. o date, most use of spinosad isin vegetable systems. An Ohio State UniversityExtension publication gives information on rec-ommended application of spinosad for controlof armyworm and cereal leaf beetle at www.entomology.osu.edu/ag/images/Small_Grains.pdf.

Tere are several formulations of spinosad onthe market; some are organic and some are not.Make sure you choose the correct one for appli-cation in an organic system. For more informa-tion, see the ARA Biorationals database atwww.attra.ncat.org/attra-pub/biorationals/.

ConclusionWhen managing diseases and insects in anorganic system, prevention is truly the beststrategy. Many of the foundational practices

of organic production, especially crop rotation,help to minimize pest pressure and promote bio-logical diversity that suppresses pests. A farmermust stay ahead of outbreaks by implementing along, diverse rotation, practicing vigilant moni-toring, selecting resistant varieties, and beingattentive to management strategies.
http://msuextension.org/publications/AgandNaturalResources/MT200806AG.pdfhttp://msuextension.org/publications/AgandNaturalResources/MT200806AG.pdfhttp://msuextension.org/publications/AgandNaturalResources/MT200806AG.pdfhttp://msuextension.org/publications/AgandNaturalResources/MT200806AG.pdfhttp://www.grainscanada.gc.ca/storage-entrepose/sip-irs/sip-irs-eng.htmhttp://www.grainscanada.gc.ca/storage-entrepose/sip-irs/sip-irs-eng.htmhttp://www.grainscanada.gc.ca/storage-entrepose/sip-irs/sip-irs-eng.htmhttp://www.sidney.ars.usda.gov/grasshopper/Handbook/index.htmhttp://www.sidney.ars.usda.gov/grasshopper/Handbook/index.htmhttp://www.sidney.ars.usda.gov/grasshopper/Handbook/index.htmhttp://ddr.nal.usda.gov/bitstream/10113/35682/1/IND43759248.pdfhttp://ddr.nal.usda.gov/bitstream/10113/35682/1/IND43759248.pdfhttp://ddr.nal.usda.gov/bitstream/10113/35682/1/IND43759248.pdfhttp://msuextension.org/publications/AgandNaturalResources/MT200806AG.pdfhttp://www.grainscanada.gc.ca/storage-entrepose/sip-irs/sip-irs-eng.htmhttp://www.sidney.ars.usda.gov/grasshopper/Handbook/index.htmhttp://ddr.nal.usda.gov/bitstream/10113/35682/1/IND43759248.pdf


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Organic Materials Review Institute. 2010. Generic Materi-als List. Database search.www.omri.org/simple-gml-search/results/spinosad

Peairs, F.B., G. Hein, and M. Brewer. 2010. Russian WheatAphid. High Plains Integrated Pest Management website.http://wiki.bugwood.org/HPIPM:Russian_Wheat_Aphid

Planet Natural. 2009. Grasshopper Control.www.planetnatural.com/site/xdpy/kb/grasshopper-control.html

Schwartz, H.F., D. H. Gent, and W. M. Brown, Jr. 2009a.Spot Blotch. High Plains IPM website.http://wiki.bugwood.org/HPIPM:Spot_Blotch

Schwartz, H.F., D. H. Gent, and W. M. Brown, Jr.2009b. Damping Off and Seedling Blight in SmallGrains. High Plains IPM website. http://wiki.bugwood.org/HPIPM:Damping_Off%2C_Seedling_Blight_SG

Skoglund, L.G. 2010. Net Blotch. High Plains IPM website.http://wiki.bugwood.org/HPIPM:Net_blotch_%28barley%29

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Disease and Insect Management in Organic SmallGrains

By Susan Tallman, CCA

NCAT Agronomist

Published April 2011

NCAT

Tracy Mumma, Editor

Robyn Metzger, Production

This publication is available on the Web at:www.attra.ncat.org/attra-pub/smallgraindisease.html

or

www.attra.ncat.org/attra-pub/PDF/smallgraindisease.pdf

IP388

Slot 385

Version 041211

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Small Grain Disease