Midterm 2008Answer the following questions about Chestnut blight

What part or parts of the tree does it infect (be specific on tissues infected)? (2pts)

What two ways does it spread to new host trees - be specific about sporestages and the ways in which each is dispersed. (4 pts)

Give two examples of other canker diseases and briefly discuss how theirmode of spread and their effects on their host are similar or different toChestnut blight. (6 pts)

Briefly explain the difference between horizontal and vertical diseaseresistance in plants, and indicate how could you tell them apart. Which is morecommonly observed in natural ecosystems? (5 pts).

Name the three aggressive tree-killing Dendroctonus species found in Californiaand describe two key characteristis of each. (9 pts)

For the western spruce budworm, briefly describe the life cycle (giveseasonality), the host trees, and the dispersal stages. (8 pts)

Outline and briefly describe the 5 components of a fire regime. What otherdisturbance factors contribute to the regime? (10 pts)

List and briefly describe weather and topologic or geographic factors that canalter fire behavior. (10 pts)

Wildland fuels are divided into four classes. List and briefly describe them.Which of these classifications is most likely to show time-lag fuel moisturechanges during daily shifts in temperature and humidity? (10 pts)

Where might you find each of the following and what would it be doing - bebrief, but as specific as possible with your answers (2 pts/each):

Phoradendron sp.

a member of the Glomeromycota

Frankia sp.

Give an example of each of the following:

a plant disease caused by bacterium (1 pt)

a fungus that produces an apothecium (looking for genus or common namehere) (1 pt)

A group of fungal-like pathogens that produce biflagellate zoospores and anexample of a disease caused by one (2 pt)

For pine trees, name one cone & seed insect, one shoot & terminal insect, andone sap-sucking insect. (3 pts)

Name two ecosystem services provided by arthropods in forest ecosystems. (2pts)

Name two ways that nitrogen is recycled from foliage to soil during defoliationof a hardwood forest. (2 pts)

Answer 2 of the following 3 questions about the readings, and if you were inthe group presenting the reading you must omit that question (10 pts/each)

From Powell’s article on responses of Lepidoptera to the fire at Point Reyes, whatwere the three groups (cohorts) of Lepidoptera, and how did the response ofthese groups post fire differ between the main types of vegetation (Bishop pineforest, chaparral and riparian). (9 pts)

For the Romme et al paper entitled "Are Large, Infrequent DisturbancesQualitatively Different from Small, Frequent Disturbances?" Describe the threepatterns of responses of plant communities to disturbance and give an exampleto illustrate each. What was the authors' answer to the title question and whatwas their reasoning.

According to Nuss et al. In their article entitled " Managing fire-prone forests inthe Western United States" what type vegetation was most adversely effected byfire suppression, and alternatively, which was least effected. What are the mainoptions for managing these systems?

Midterm 2007Questions about the readings: Answer 2 of the 3 and if you presented the paperin class you must omit it.

1) Answer the following about the Lovett et al. article on insect defoliationand the N cycle in hardwood forests. (8 pts)

During defoliation, foliar N is diverted to what three components?

For the 15N tracer experiment in small trenched plots, what were the twotreatments?

How did the fate of the recovered 15N differ between treatments?

2) Answer the following about the Noss et al. article on managing fire-poneWestern ecosystems (8 pts)

What types of areas did they focus on?

how did their management recommendations differ with fire regime?

what was their recommendation for post-fire logging?

what did they state as a "common sense goal"?

3) Answer the following about Powell's study of post-fire insect recovery atPt. Reyes (8 pts)

What group or groups of insects did he study?

How did he go about looking for them?

What were some of the problems he encountered?

Name two major findings

4) Describe the general life cycle of Brown Spot Needle blight, the conditions(plural) under which it is likely to be problem, and its interaction with Long LeafPine and fire. (10 pts)

5) Douglas fir tussock moth is the most important forest defoliator in California.Which two conifers are affected, how many generations does it have each year,what is the dispersal stage in the life cycle, and what is the most importantnatural enemy? (8 pts)

6) Outline and briefly describe the 4 wildland fuel categories. Which of thesetypes of fuels is most often the major concern in terms of producing wildfiresthat are uncharacteristically severe in ponderosa pine and mixed conifer forests?(10 points)

7) You are the fire management officer on US Forest Service lands in a portion of theTahoe National Forest. This area is dominated by mixed conifer forests and it covers100,000 acres. You have been asked to develop a plan to reduce fire hazards in this area.You cannot treat all of this area in 1 or 2 years. Outline the procedure and briefly describesteps that you would take to address this problem. (10 points)

8) The impact of Dendroctonus bark beetle species can vary from being tree killersto obligate tree parasites. Give an example of a tree killer, a secondary species,and an obligate parasite and briefly explain how the use of aggregationpheromones, fungal associates, and egg niches differ between these three groups.(9 pts)

Short answers

In a gene for gene system, where capitol letters indicate dominant genes, given apathogen genotype of A1a1 a2a2 a3a3 circle all host genotypes that could beinfected by it (4 pts):

R1r1, r2r2, r3r3R1r1, R2r2, R3r3r1r1, R2r2, r3r3r1r1, R2r2, R3r3r1r1, r2r2, R3R3r1r1, r2r2, r3r3;

Other than geographic range, what is different between eastern and western gallrust? (2 pts)

What is the shortest time period needed for an dwarf mistletoe (Arceuthobiumspecies) to go from seed to seed? (2 pts).

What are two ways Arceuthobium species are dispersed and approximately howfar can they move by each (4 pts).

What type of forest composition and structure would be ideal for the spread ofArceuthobium and why (4 pts)

How is ozone formed in the lower atmosphere and what the common humancomponents and sources in this process (4 pts)

What are the two main groups (Phylla) of true fungi that make up the majorityof plant pathogens? (2 pts)

Which of the above groups of fungi are the major causal agent for wiltdiseases? (2 pts)

Which of the above groups of fungi are the major causal agent for cankerdiseases? (2 pts)

What two different types of spores are often used by these fungi? (2 pts).

Name two different forest insect feeding groups that use symbionts to augmenttheir nutrition; briefly indicate the role of the symbionts in each case. (4 pts)

What ages of foliage are used by conifer sawflies for (1) egg laying and (2) larvalfood? (2 pts)

Name one cone insect, one sap-sucking insect and one wood borer that can befound on lodgepole pine in the Sierras. (3 pts)

Midterm 2006

What is pyrodiversity? How has it changed in the last 100 years in SierraNevada mixed? conifer forests? How has this change affected forest insects anddiseases? (8 pts)

What are the 2 general methods that can be used to reconstruct fire history inforests? What forest types are appropriate for these methods? Why? (8 pts).

What are the 3 fundamental variables that influence fire behavior? Give abrief explanation on how each of them impacts fire behavior. (9 pts).

Briefly define the Climax view of plant communities, give two major problemswith it, and discuss the main components of the modern view of plantcommunities. (8 pts).

Briefly describe a gene-for-gene model of plant resistance and in your answerexplain 1) how a resistant plant reacts to infection, 2) the genetics behind thisreaction for both the plant and the pathogen; 3) and a simple model for howthese genes (or their products) interact. (8 pts).

Briefly describe 3 different groups of wood boring insects, whether they haveknown fungal associates, and where the larvae feed. (9 pts)

What is the difference between complete and incomplete metamorphosis ininsects, why has it been important to the success of insects, and name 2 groups(orders) of insects that have complete metamorphosis. (8 pts)

List 4 different ways in which disturbance by insect defoliators increases thephotosynthetic rate of forest trees. (8 pts)

Answer 2 of the following 3 questions about the readings. If you lead thediscussion on the paper listed you must omit that question and answer the twoothers.Clearly indicate which questions you are answering with A, B, C.

A) How would Romme et al. (the paper you read last week) define athreshold versus a continuous response to disturbance – give a plantcommunity example for each. (8 pts)

B) According to Agee how did patch size and edge historically interact withfire severity? What has changed in this interaction with fire suppression? (8pts)

C) Briefly describe the significance of the three cohorts (functional groups) ofinsects that Powell considered in monitoring the recovery of Lepidoptera afterthe fire at Point Reyes, and explain how Powel sampled the area for these (8pts)

Midterm 1 2004

List six components used to describe a disturbance regime, and briefly defineeach with a short phrase. (12 pts)

Name two pools of nitrogen that are typically unavailable to plants, and brieflyprovide four examples of ways in which interactions of insects, microbes or firecan make these pools more available. (10 pts).

Briefly define or give an example of each (2 pts each) ;A phoenicoid fungus

An Oomycete

A shade tolerant tree

An early-stage ectomycorrhizal fungus

An epiparasitic plant

Given a gene-for-gene system, a pathogen genotype that could cause diseaseon plant with following genotype R1r1, r2r2, R3R3,

A modification of insect mouth parts that adapted it to a specific food.

A key function for the epicuticle layer of the exoskeleton of insects.

fly discuss four of the six key explanations for the success of the insects as agroup of organisms? (12pts)

List four ways in which insects can be beneficial in forest ecosystems. (8pts)

Provide two examples in which symbionts enhance the nutritional status of plantfeeding insects. (4pts)

List three groups of sap sucking insects found on forest trees, and indicate whichgroup is most likely to kill trees. (8pts)

Your goal is to quantify the past fire regimes in 2 forest types, ponderosa pine inthe Sierra Nevada and Rocky Mountain lodgepole pine near YellowstoneNational Park. What methods would you use and why? (10 pts)

What is pyrodiversity? How has this changed in coastal Bishop pine forests innorthwest California? Explain. (10 pts)

List 4 of the 5 most common types of wildland fire ignition sources. Is it possibleto predict where these types of ignitions will occur most often? (10 pts)

What variable would you use to quantify the flamming front of a fire? Why? (5pts)

Midterm 2 2004List the three most important genera of bark beetles that attack conifers inCalifornia, and indicate for each genus whether attacks are initiated by male orfemale, whether mycangia are present, and whether they are monogamous orpolygamous. (9 pts)

Briefly describe the life cycle and biology of horntails (Siricidae). (6 pts)

Briefly describe the following (3pts each):The two most important groups of wood feeders found on trees logged inlate summer

The three different larval feeding niches found among sawflies found onhardwoods

The three dispersal stages of Choristoneura budworms

An eruptive population outbreak

An idiobiont parasitoid

Three trees that could be hosts for dwarf mistletoes

An example of a fungus that causes a brown rot, and an explanation of whata brown rot does to the wood.

What does a laminar rot do? and what is an example of fungus that causesone.

How is leafy mistletoe dispersed, where are you likely to find it in the tree,and name a tree that could be a host.

Provide the names, host tree associations, and voltinism of one defoliator fromeach of the three main groups (sawflies, moths and beetles). (6 pts)

Briefly describe, with examples, the three main types of factors that influence thefavorability of the environment for a forest insect population. (9 pts)

List the four different groups of insect pathogens, the mode of infection for eachgroup, and explain why only one of these groups is found on sap sucking insects.(6 pts)

Answer the follow short questions are insect/disease interaction in Yosemitevalley.

What was the main root disease and insect involved (be specific as possible) (2pts)

What tree species were involved and how did they interact with the insect anddisease that you list above. (4 pts)

Briefly discuss three management decisions or past human activities that affectedthis interaction and explain the effect of each. (6 pts)

Briefly discuss the differences in the ways that heartwood and sapwood aredefended against wood decay. (4 pts).

Briefly discuss the spread of dwarf mistletoe through a forest. How does itoccur? What factors of the pathogen lifecycle and forest structure could limit oraccelerate the rate of spread. (4 pts)

Describe at least three different factors that could create an ideal setting for aserious problem with Red band needle blight, and explain your reasoning foreach in relationship the life cycle and behavior of this disease.

Briefly discuss three specific examples of diseases that might be expected toincrease as a result of other insect or disease problems. For each give an exampleof the specific type of predisposing agent, and tell how or when the diseasemight arrive at the site. (9 pts)

Midterm 1 2003

1. (10pts) Describe four ways that seed and cone insects damage the fruitingstructures of conifers. Give an example of each type of damage (commonname or Genus).

-1. (6pts) Define the urban forest and give two examples of the problems confronting a pest control manager in urban environments.

3.     (8 pts) Briefly describe four ways that insects and diseases benefit forestecosystems.

4. (8tps) Briefly compare dwarf mistletoe to leafy mistletoe in terms of:

1) mode of dispersal

2) host range and specificity

3) position in tree

4) effects on host trees

5. (8 pts) Compare ectomycorrhizal and arbuscular (endo) mycorrhizal in termsof:

plant hosts involved

Morphology

Fungi involved

Costs and benefits to plants

6. (2pts)What is an ascus? and where would you expect to find it?

7       (2 pts) What is a resupinate fruit body and which group of fungi makethem?

8. (4 pts) List the three main factors that directly or indirectly effect soil microbialcommunities in a post-fire environment. Of these three which one is likely to havethe least effect? Briefly explain.

9. (8 points) Fires are complex and variable. What concept can is used to describethe historical pattern of wildland fires in a given ecosystem? List the componentsof this concept.

10) (6 points). What are the 3 fundamental variables that influence fire behavior?Give a brief explanation on how each of them impacts behavior

11) (10 points)What is pyrodiversity? How this changed in Sierra Nevada mixedconifer forests over the last 100 years? How about coastal Bishop pineforests in northwest California? Explain.

                          MIDTERM # 2 – ESPM 134 – FALL’03

(6 pts) 1) There are three principal ways that damage caused by insects augmentslosses

to forest fire. What are they?

(4 pts) 2)  What are the four principal groups of insects that are attracted to firedamaged trees? Give either family or common name.

(2 pts) 3)  List the two most important insect pests of wood in use or service (drywood).

Common or family name.

(10 pts) 4) There are three important genera of Scolytidae (bark beetles) inforestry

world wide. List these genera. Discuss the differences in life history(at least

three) between polygamous and monogamous species of bark beetlesand

give an example (Genus) for each.

(4 pts) 5)  Bark beetles have a number of different types of associations withfungi.

Briefly describe four of them.

(6 pts) 6)  The life history of a defoliator must be considered in the developmentof any

pest management program. List three life history traits that could beimportant

and give an example for each (common or scientific name).

1)The 2002 Hayman fire in Colorado was characterized as an ecological disasterby most land management agencies. Was it a disaster? How would you describe itecologically?

7 points

2) What is the Historic Range of Variability and why is it important in land

management?

5 points

3) List and contrast the old and new terminology used to describe wildfire fires?Why was this changed?

7 points

4) List what prescribed fire incident commanders have to integrate when planninga prescribed fire.

5 points

5) What type of prescribed fire ignition pattern would you use to produce a lowintensity fire? A moderate intensity fire? A high intensity fire?

5 points

6) What is a fire surrogate? Why are they becoming common with forestmanagers? Do they have limitations?

7 points

7) You are designing a forest restoration plan for Sierra Nevada ponderosa pineforests. These forests one experienced low intensity fires every 5-10 years. Firesuppression has eliminate fires for the last 100 years. Your goal is to reduce fuelhazards and to promote natural pine regeneration in an area of 10,000 acres. Whatdo you propose? What are some problems and opportunities? 10 points

Give an example of a fire interaction that releases a tree from a pathogen and

briefly describe how it works.

When does gall rust infect and through what tissue?

How do blue stains infect a tree and what to they do to it.

Describe the basic disease cycle of Red band needle blight Scirrhia) pini,(Dothistroma pini) 10 Pts

 

 

Name a host and a geographic region where you expect this pathogen tokill its host.

Name a host and geographic region where you would expect to thispathogen to be present but have a minor impact on its host.

Briefly discuss two possible reasons for the difference in behavior.

Name three different root disease that are complexes of cryptic species or host

specific varieties, and for each give an example of two of the species or varietiesand the host preferences associated with them (9 pts).

11) Question from readings - Briefly outline the fate of nitrogen followingdefoliation of a forest by an insect like the gypsy moth. (4pts.)

Midterm 2spring 2002

I. Briefly outline the life cycle of dwarf mistletoes (Arceuthobium), indicate thetime it takes to complete, and discuss factors that limit its rate of spread in a forest.(10pt)

II. Describe the types of changes that are typical in the soil microbial communityfollowing a stand-replacing fire, and discuss some of the direct and indirect effectsof fire that drive these changes. (10 pts)

III. Compare the two organisms in each of the pairs with respect to the attributeindicated. (10 pts)

The way Rhabdocline weirii vs. Rhabdocline parksii interact withDouglas fir

The inoculum source for early-stage versus late-state mycorrhizal fungicolonize roots

The host ranges of Heterobasidion annosum S vs. P stains

The typical canopy position of Leafy mistletoes vs. dwarf mistletoes

The importance of conidia in needle blights versus needle casts

IV. For each of the defoliators listed below give the attributes of their biology thatmust be considered in any control or management attempt. (10pts.)

a) Larch sawfly - Pristiphora erichsoni

b) Spruce budworm - Choristoneura fumiferana

c) Lodgepole needle miner - Coleotechnites milleri

d) Fall webworm - Hyphantria cunea

e) Pandora moth - Coloradia pandora

V. Describe at least five different associations that the family Scolytidae have withfungi. (10 pts)

VI. Compare the polygamous species of bark beetles with the monogamousspecies and give the Genus that is an example of each type. (8 pts)

 

Midterm 1 spring 2002(6 pts)Briefly describe the difference between horizontal defense andvertical defense and give examples of the type of plant responses involved.

(10 pts)Briefly compare white pine blister rust (Cronartium ribicola) to Gallrust (Peridermium harknessii) in terms of:

host range

complexity of life cycle

conditions necessary for infection

site of infection on pine.

effect on pine host.

 

(6 pts) Briefly discuss the differences between the ways in whichheartwood and sapwood are defended from wood decay organisms.

(6 pts) For the three categories below list the fungal group (Ascomycetes,rust fungi, other Basidiomycetes) that are most responsible orcharacteristic for each disease type or process.

Wood decay

Foliage diseases

Spread by mitotic spores

 

(10 pts) Briefly discuss five beneficial ecological roles that insects play inforests.

 

(5 pts)Give five characteristics of the Class Insecta

 

(5 pts) List five attributes of the urban forest that a pest manager wouldhave to consider.

 

(2 pts) Give the Class of an organism in the subphylum Chelicerata andone in the Mandibulata (other than Insecta).

(2 pts)How do insects breath?

(2 pts)Give two examples of insect pests of forest regeneration, eitherscientific or common name.

2 pts)Give two examples of important insects in the urban forest, eitherscientific or common name.

 

(8 points)The following equations can be used to calculate firelineintensity.

 

I = hwr  I is fireline intensity, h is heat of combustion in kJ/kg, w is fuelload                              in kg/m2 and r is the rate of spread of the fire inm/sec.

 

I = 259L2.17 I is fireline intensity, L is flame length in meters.

 

Which equation or equations would you recommend to estimate firelineintensity in an understory prescribed fire in mixed conifer forest? Why?This forest has experienced fire suppression for the last 80 years.

 

(8 points)What is pyrodiversity? How has pyrodiversity of the coniferousforests in California changed in the last 80 years? Explain your answer.

 

 

(12 points) What are the 2 general methods that can be used to reconstructfire history in forests? What forest types are appropriate for thesemethods? Why? .

 

Midterm 2 Fall 2000

1) A. Discuss the stand structure, plantgrowth strategy and adaptations to fireexhibited in lodgepole pine forests (6).

B. What are three unique biological attributesof the lodgepole needle miner? What are thepossible bark beetle and disease interactionswith the needle miner? (6)

3) Give 3 reasons spruce budworm isdifficult to control with chemicalinsecticides? (6)

4) Discuss one direct and one indirectpotential effect of climate change on the fireregime of mixed-conifer forest of the SierraNevada. Please be specific about the changein climate scenario, forest type or communitycomposition and direct versus indirect effects.(8)

5) Briefly describe, or list, three ways a canker can formon a tree and give an example of an agent can could causeeach (6 pt)

6) Refer to the above figure and fill in the table indicatingwhether early or late stage ectomycorrhizae would beexpected and indicate likely inoculum source. (6)

Source of roots: late stage or early stagemycorrhizae ?

Likely source ofinoculum?

A: mature tree from theedge of the root system

B: mature tree near thetrunk

C: seedling planted inundisturbed soil neartrunk

D: seedling planted insmall sealed cylindernear the truck

E: seedling planted insoil removed from belowmature tree

mature tree

F: seedling plantedoutside root system ofmature tree

Briefly explain how your answers would change if the treewas Ponderosa pine and the seedlings were incense cedar?(2)

Short Answers --

1) Name two forest defoliators that are considered to beoutbreak species. (2)

2) List two forest defoliators that are examples ofsuccessful biological control programs. (2)

3) Name two pathogens that are serious problems primarilywhen their hosts are planted off-site. (2)

4) Name three types of plant tissue that requireprotection from fire. (3)

True or False (1pt each, and correct any falsestatements for an additional point.

1.     The lethal high temperature range for plant celldeath occurs between 50 and 60 o C with very littlevariation either among species or for different kindsof tissue.

2.    Lodge pole pine bark is very resistant to fire.

3) VAM fungi use the ability to degrade celluloseand lignin to scavenge Nitrogen from soil organicmatter.

4) Nematode trapping fungi are widespreadand common in soil.

5) Rhabdocline parksii is an important pathogen of

Douglas-Fir

6) Ericoid mycorrhizae dominant in settings withhigh pH, such as tropical rain forests.

7) Nitrogen is the most limiting nutrient in Sierramixed conifer forests

 

Midterm 1 Fall 2000

Name the major chemical components of wood and briefly discuss theway and relative ease with which each is degraded during the process ofwood decay (8 pts).

 

Discuss five factors that influence fire behavior, overall which is themost important and why (6 pts)?

Briefly discuss the differences or similarities between dwarf mistletoeand leafy mistletoe with respect to each of the following (6 pts):

mode of seed dispersal

host range

effect on hosts

Discuss five ways that insects and diseases benefit forest ecosystems. (10pts.)

 

Give a short definition of each of the following (2pt each):

rhizomorph

Climax forest

 

Head fire

 

Fire return interval

Give an example of each of the following:

Two abiotic pathogens (2 pt)

Two shade intolerant tree species (2 pt)

Two climatic factors that vary with altitude, and tell how they vary (2 pt).

A root disease that does not cause decay (1 pt)

 

The ignition source for most naturally occurring fires (1pt)

Two examples of insect outbreak species and their hosts. ( 4 pts.)

The common name of one mandibulate and one chelicerate arthropod (2pts.)

Short Answer:

 

How does flame length vary as a function of topography and/or wind (3pts)?

 

Why is fire danger highest in the late summer and fall in California (3 pts)?

List four ways that a ponderosa pine could be predisposed to bark beetle attack,and name two beetles that would be likely to be involved first. ( 6 pts.)

 

 

 

 

Midterm 2 1999

1) Discuss the major interactions of insects, fire, disease and human activities thathave lead to the transformation of Oak savanna and meadow communities intoponderosa pine/incense cedar forests in large parts of Yosemite valley. Be asspecific as possible with respect to the insects and diseases, and fire regimesresponsible (20 pts).

2. The initial composition of a forest is equally divided between Douglas fir andPonderosa pine. Describe the likely changes in species composition of this forestgiven the following scenarios. Include in your discussion what species is favoredunder these conditions and why, and if there are any likely insect or diseaseinteractions include them. (20pts)

A. The trees in the forest have reached pole size when a low-intensity ground fireoccurs.

B. The forest has reached a stage where there are mature trees, Ponderosa pine isthe dominant species and Douglas fir is abundant in the understory. A low-intensity ground fire occurs.

C. Same conditions as in B, but a high intensity crown fire occurs.

D. Pole size trees of both species with an equal mix and fire is suppressed.

3) Briefly discuss the benefits and risks of biological control programs. (6)

4) Give three families (scientific or common names) of insects that

would be found in fire salvage timber. (3)

5) Give two possible explanations for how bark beetle natural enemies

find their hosts. (4)

6) Give one unique or important aspect of the biology for each of the

following forest defoliators: (3)

A) Spruce budworm - Choristoneura fumiferana

B) Pandora moth - Coloradia pandora

C) Larch sawfly - Pristiphora erichsonii

5) List and briefly explain five beneficial effects of non-pathogenicmicroorganisms in forest systems. (5 pts).

6) What are the beneficial roles of pathogenic insects and diseases in forest

ecosystems; explain each briefly. (6)

7. .Many plant species have evolved adaptive traits that help them survive fires orreproduce after them. Discuss three different adaptations or strategies that plantsuse to survive and/ or persist after fire, and give examples of plants that use each(6 pts)

8. What are the atmospheric products of fire? Discuss the associated health and /orair quality concerns with smoke in general? (10pts)

The following questions relate to the articles about extinction ofectomycorrhizal fungi in Europe.

List three types of evidence that Arnold used to argue that many speciesof ectomycorrhizal fungi were becoming extinct in Europe. (3pts)

Briefly discuss three other possible explanations for Arnold'sobservations and data, and explain how Arnold argued against theseinterpretations and discuss any weaknesses you see in his arguments. (6pts).

Midterm1 1999

1) List the six most likely dominant trees species one would encounter in a "mixedconifer" forest in the central Sierras at about 4000 ft, and underline those speciesyou expect to find in the understory of an undisturbed forest (17 pts).

Which of these species can be hosts for dwarf mistletoe?

Select one potential host species and discuss the forest conditions suchas stocking level, age structure, and species composition, and climaticconditions under which dwarf mistletoe would be able to spread rapidlyand have the maximum detrimental effect on its host or hosts.

2. Using a diagram of a flame, illustrate and discuss the three stagesof combustion. How might flame characteristics vary with wind andchanges in topography? How might fireline intensity change as a result?(8 pts)

3. What are the major components that describe the fire regime of agiven ecosystem. What is the characteristic fire regime for mixed conifer

forests of the central Sierra Nevada (pre-fire suppression)? (10 pts)

4) List and discuss briefly five beneficial roles of insects in forestecosystems. (10pts.)

5) You receive a phone call from a forest manager and youare told that 50 acres of 100 year old ponderosa pine in theSierra Nevada at 5500 feet have been scorched by a fire. Sheasks are there any potential insect problems? Give the completescenario of what might happen insect-wise. (10pts.)

A.) She also has several root disease centers in white fir infectedwith the S-strain of Heterobasidion annosum. What are thepotential insect problems and what should she do? (5pts.)

6) Briefly compare the similarities and difference between the ways andconditions under which Blackstain root disease and Armillaria mellea infectionsare initiated, spread, and persist within a site. (8 pts)

Midterm1 1997

1) Give an example of a ideal setting for the initiation and spread of the P strain ofHeterobasidion annosum. Your answer should include details of the treecomposition, age structure, and disturbance history and a brief explanation of howthese parameters affect the disease. (8 pts)

In the forest you describe above which host would be mostsusceptible to a primary tree-killing bark beetle? List a likelybeetle. (2 pts)

Would this forest also be susceptible to Armillaria root

diseases? If not explain why and if so give a possible scenariofor an initiation of an Armillaria infection. (4 pts)

Briefly discuss how past fire history could either positively ornegatively affect the likelihood of Armillaria and its spread ratethrough a forest. (2 pts)

2) Other than mycorrhizae, list four positive functions of microorganisms in forestsystems. (4 pts)

3) Compare Ectomycorrhizal and VAM symbiosis with respect to the following:

contribution of the plants vs. contribution of the fungi

examples of the major groups of fungi and plants involved

dependence of the fungi and plants on the symbiosis

ecological settings where each mycorrhizal type dominates (8pts)

5)What is the basis of fire? Write the chemical equation. (4 pts)

6) Using a diagram of a flame, illustrate and discuss the three stages ofcombustion. (6pts)

7) Fire behavior is a function of several determinants. What are these determinantsand how might they influence fire behavior? (8 pts)

8) What are the major components which describe the fire regime of a givenecosystem. Use them to describe the typical pre-20th century fire regime for themixed conifer forests of the Sierra Nevada (8 pts)

9) Why are insects such a successful group of organisms ? Give at least four ofwhat you consider to be the most important reasons in your discussion. 7 pts.

10) Discuss the ecological roles that insects play in forest ecosystems. Cover atleast five different roles in your discussion. 10 pts

11) Discuss three unique aspects of the biology of the family Scolytidae- barkbeetles. 6 pts.

12 List the three most economically and ecologically important Genera of barkbeetles in the United States. 3 pts.

Midterm 2 1997

I. about those readings you did:

List three types of evidence that Arnold used to document the pattern ofextinction of ectomycorrhizal fungi in Northern Europe. (3 pts)

If you do not want to accept his hypothesis, that these fungi aredecreasing dramatically in abundance, does he make any assumptionsthat weaken his conclusions? (2 pts.)

What does Arnold think is the likely cause of the decline? Name twoother possible causes that he considered, and explain why he rejectedthem. (4 pts)

Mattson and Addy in their paper on forest insects as regulators ofprimary production discuss how insect grazing or feeding might affectthe rate of photosynthesis. Give three ways this might happen. (6 pts.)

 

More readings

Answer the following with True or False:

. Live and dead fuels in today's mixed-conifer forest are moreabundant and less continuous than in the past. (1 pt)

. In most low-elevation oak woodland and mixed-conifer foresttypes of the Sierra Nevada, presettlement fires were frequent, collectivelycovered small areas, and burned for months at a time. (1 pt)

. Timber harvest, through its effects on forest structure, localmicroclimate, and fuel accumulation has increased fire severity morethan any other recent activity. (1 pt)

II. Using a diagram, discuss the relationship among land- clearing, alien grassspecies invasion and the grass-fire cycle. Make sure to include the directionalchanges and potential feedbacks in the cycle as well. (8 pts)

III. Fire suppression in the Lake Tahoe Basin has had several directeffects on mixed conifer forest. Discuss three of these effects. (6 pts)

How might fire be safely and effectively reintroduced into this system?(3 pts)

 

 

 

IV. Using observations from the previous two fieldtrips, what is therelationship between fuel consumption and mortality of shrubs and trees?(4 pts)

V. Many plant species have evolved adaptive traits that help themsurvive fires or reproduce after them. Name the adaptations for thefollowing species (3 pts):

            Ceanothus

ponderosa pine

knobcone pine

VI. Give an example of a needle cast and a needle blight disease, contrast theinfection cycles of the two, and discuss conditions under which each mightbecome a serious problem. (10 pts)

VII. If you were given the job of trying to maintain a Lodgepole pineforest at Donner State park - primarily for aesthetic reasons - , whatwould you expect to be major insect and disease problems (name one ofeach), and how would you try to lessen these if fire was not an option? (6pts)

What is the natural fire regime for this forest and would it be possible tomimic it with the prescribed burning? If so, explain how you might goabout it and if not explain why? (4 pts)

Assuming you introduced a prescribed burning program in this forest,

name 3 specific insect related risks and discuss the sequence of insectarrivals in each of these. (6 pts)

continued Donner lake example

Give two examples of organisms other than insects that might be affectedby the use of fire in this system and briefly explain the impact of these onthe forest community. (4 pts)

 

List three families - scientific name preferred-- of insects that you wouldbe likely find in timber salvaged following a wild fire. (3 pts.)

VIII. Define biological control. (2 pts.)

a.) Give three reasons why biological control programs in forestry mightbe approached differently than those in agriculture. (3 pts.)

b.) What would you suggest as the best approach to biological control ofa forest pest and why? (2 pts.)

c.) Give one example of a successful biological control program inforestry. What approach was used? (2 pts.)

IX. Given a mixed conifer forest in Blodgett with approximately equalcomponents of Douglas-fir, ponderosa pine, sugar pine, white fir, incensecedar, and black oak. Answer the following questions:

Independent of any management decisions which of these species islikely to decrease in abundance over the next several hundred years andwhy? (2 pts)

If this forest was converted into an even-age, dense monoculture ofPonderosa pine which insects or diseases (name one each) would havethe greatest potential to wipe it out. ( 2 pts)

Midterm 1996

Given a ponderosa pine in the Blodgett or Yosemite area with redfoliage, Name four bark beetles that would be likely to be found within

the tree and specifiy what would their locations be? (8 pts)

Name a total of four pathogens that would be likely to have predisposedthis tree to attack or might have colonized as a direct or indirect result ofbeetle attack. (4 pts)

Discuss two plausible temporal sequences for colonization of these beetlesand pathogens. Each sequence should contain all of the beetles and at leasttwo of the pathogens. (8 pts)

II. Short answer 2 pts each:

Given a gene for gene system list two fungal genotypes that could colonizethe following host genotype:

R1r1 r2r2, R3R3, R4r4

Which of the following four plants could share the same mycorrhizalfungi, and types of mycorrhizae are shared:

Incense cedar, Douglas-fir, Ceanothus cordulatus, Arctostaphylos viscidus.

Which, if any of the above plants, have symbiotic nitrogen fixation andwhat is the genus of the associated nitrogen fixer.

Name two beneficial affects of microorganisms other than mycorrhizae ornitrogen fixation, and if possible give an example of an organism orspecific group of organisms for each.

III. Give three specific examples of fungal species that are actuallyspecies complexes composed of reproductively isolated cryptic speciesor varieties, For each list at least two of the sub-specific taxa. (6 pts)

Select one of the above examples and discuss the biological and ecologicaldifferences among the sub-specific taxa. (6 pts)

1995 midterm questionsContrast complete (holometabolous) and incomplete (hemimetabolous)metamorphosis in insects, and name three orders that are important inforests that exhibit each type of metamorphosis. (8)

Name the organ systems of insects (7)

Name two morphological structures that are used to classify the orders ofinsects. Give 3 examples of orders that are defined by one of thesemorphological structures and state what the order name of the ordermeans. (6)

List the 4 fire regime characteristics (4)

For 2 of the following 3 sites that we visited on the Yosemite trip discusswhich of these fire regime characteristics changed from the prehistoricalregime and briefly mention what the consequences of these changes havebeen on the vegetation present at these sites. (8)

Site 1 the Yosemite Valley site, the near campground.

Site 2 the prescribed burn near Crane Flats that was still smoldering.

Site 3 the 1991 Foresta wildfire site.

Given a forest dominated by ponderosa pine in which the pines areinfected with both Heterobasidion annosum and mistletoe answer thefollowing questions.

What strain of Heterobasidion and what type (or genus) of mistletoewould you expect on the Ponderosa pine? (2)

This forest would be likely be predisposed to what tree-killing insect?Name one other agent that could also cause such predisposition. (2)

The average rate for the mistletoe to spread through such a forest is 1 to 2ft/yr; this is almost identical the to rate of spread for Heterobasidionannosum How do each of these pathogens spread locally and why ismistletoes so slow? (4)

Assuming a similar forest without either pathogen what is the likely wayfor each to arrive at the site and initiate new disease (4)

If the forest had an understory of incense cedar and white fir what wouldyou expect the species composition to look like after both pathogens haverun their course. Explain you answer. (4)

If a stand replacing fire killed all of the tree in this forest would one orboth of these pathogens survive it? If so how. (3)

Briefly discuss the difference between the terms in each of the following

sets and provide an example an organism that would produce each:

hyphae/rhizomorphs (2)

Sexual spore/ asexual spore (2)

List four ways that plants survive a fire or recolonize after it and give anexample of a specific plant for each (8)

1994 midterm questionsI. Compare and contrast the P strain of Heterobasidion annosum to Armillariamellea in terms of each of the following:

What phylum of fungi to which each belongs (i.e., Ascomycota,Basidiomycota, Zygomycota). (2 pts)

What type or types of spores do each produce. For each spore indicatewhether it is sexual (i.e., produced via meiosis) or asexual (mitoticallyproduced), and if known, give the nuclear condition (haploid, diploid, etc.)(2 pts)

Host ranges of each (4 pts)

How does each spread within an infection center (4 pts)

How are new infection centers initiated (4 pts)

What are the symptoms of host infection (4 pts)

II. Name 3 ways insects can effect trees. What are the resultant changes instand parameters for these insect caused effects. (6 pts.)

III. How has human activity influenced insect-caused tree mortality inYosemite valley. (8 pts).

IV) Judging from the general information on forests passed out at thebeginning of the course, what are some of the consequences of theprojected increase in human populations on the sustainability of NorthAmerican forests and on forests elsewhere. (6 pts)

V) Describe the four characteristics of fire regimes and the relation of eachto the role of fire in ecosystems. (8 pts)

VI) Select two of the following four sites that we visited on the Yosemite

trip:

a) the stop just outside of Groveland (afternoon day 1)

b) the meadow and adjacent forest near the campground (after breakfastday 2)

c) the prescribed burn and adjacent unburned forest (valley on the wayout)

d) the wildfire on the top of the hill in west end of Yosemite (Floresta fire)

Then for each describe:

1) the observed pattern of survival and regeneration of plant species. (6pts)

2)Explain the patterns described (i.e., in part 1) in terms of thecharacteristics of each fire or fire history of the site and the fire survivalstrategies of the individual species. (6 pts)

Compare dwarf mistletoe to leafy mistletoe with regard to each of thefollowing: Host ranges, Mode of dispersal, common position in crown,effect on host tree. (12 pts).

Describe a forest in terms of species composition, stocking, and agestructure that you would expect to be especially prone to attack by dwarfmistletoe, and briefly explain why.

Where would you expect to find Oligoporus amarus (pecky rot)? Be specificin terms of host if any, and type or age of forest if this is important. (2 pts)

Is it an obligate parasite or a saprobe? What is the problem with classifyingit as one or the other? (2 pts)

What type of decay does it cause and what parts of the tree are effected. (2pts)

1993 midterm questions1 Compare Blackstain root disease and Bluestains in terms of the waysthey spread, the way they look, the tissues they colonize, and thepathogenicity. (8 pts)

2. What are the three necessary components for plant disease (i.e, thedisease triangle)? Select a forest tree disease other than Blackstain orBluestain and use it to discuss specific examples of each of thesecomponents. (6 pts)

3. In the Tahoe basin you observed large numbers of dead or dying whitefir trees. Name a specific insect and a specific pathogen that you expect tofind in most of these trees. (4 pts)

4. Name two human actions that have contributed to these problems atTahoe and briefly explain the effect of each. (4 pts)

5. Name the two body structures most frequently used to classify insectsinto orders. (4 pts).

6. What evidence is used by biologist to justify the the "success" of insectscompared to other life forms (2 pts)

7. Give three examples that support the following statement: " insects andpathogens are closely associated in nature" (6 pts)

8. Give three examples of ways in which fire or lack thereof influenceinsects and pathogens. (6 pts)

9. List and describe the four major characteristics of fire regimes. Give anexample of how each might affect the fire, insect, or disease interactions ina forest (Pick any wildland situation you want) (10 pts)

10. Describe the six attributes of fuels and discuss how each might affectfire behavior. (6 pts)

11. Define fireline intensity and fuel consumption. (4 pts)