2008 Final Synthetic question two plant communities

Transcription

1 2008 Final Synthetic question 1) Select two plant communities you have read about, discussed or visited during this course and use what you know about insects, fire, and disease in these communities to discuss the following question: Does the disturbance regime define the plant community or does the plant community create the disturbance regime? First list the dominant members of the community, and discuss the most important disturbances in these communities. You need not mention all insects, fire, or diseases interactions with a particular community, but be sure to cover at least two of the three agents of disturbance in each community, and discuss the effect of these agents on either maintaining or removing the dominant plants. This question will be graded primarily on the quality of your examples and your reasoning behind your answer. (16 pts) Questions from class readings Answer questions from 2 of the following 3 class readings below. If you presented the paper, you have to omit that one. 2) From the Lovett et al. reading on insect defoliation and nitrogen cycling in forests answer the following (6 pts): Does defoliation generally lead to retention or export of nitrogen from a forest ecosystem? (2 pts) What is the biggest change in the fate of foliar nitrogen as a result of defoliation? (2 pts) What is throughfall and how important do you think this would be in California forest ecosystems? (2 pts) 3) According to Stephens & Moghaddas in their paper on "Experimental fuel treatment impacts on forest structure, potential fire behavior, and predicted tree mortality in a mixed conifer forest" what are the pros ands cons of the retention of coarse woody debris before and after a fuels treatments as discussed in Stephens and Moghaddas (2005). (6 pts) 4) Using the information in the D'Antonio Vitousek paper on "Biological invasions by exotic grasses, the grass/fire cycle and global change" answer the following: Name two ecosystems in which invasive grasses have changed the fire cycle. (2 pts) Explain what parts of the fire regime grasses change and how they do it. (4 pts) Longer answers 5) Give three examples of heartrot fungi, for each list the host and the type of rot it causes, then briefly discuss ways in which heartrot fungi might enter the tree, and the effect they have on the host. (10 pts)

2 6) Briefly discuss the life cycle of brown spot needle blight. Include in your answer any relevant about types of spore, host tissue infected, and weather conditions, and then describe the unique interaction between brown spot needle blight, long leaf pine, and fire and. (10 pts). 7) Briefly discuss the way that Armillaria mellea behaves in California mixed conifer forests. How does a disease center usually start? What are its hosts, how does it spread? (10 pts) 8) Draw and describe, using an properly labeled illustration, the concepts of frontal, flanking, direct and indirect attack on a fire. (8 pts) 9) What types of treatments may be possible surrogates for wildland fire? Discuss why forest managers would embrace or reject these treatments in Sierran mixed conifer forests. (10 pts) 10) Fire hazard reduction assessment is a four step process. List & briefly describe the four ways to assess wildland fire hazards. What is the one political wildcard in this assessment? (10 pts) 11) Describe the effects of a low-intensity, low-consumption fire in coniferous forests. How would you ignite it? Be specific! (8 pts). 12) Answer the following questions about beetles (Scolytidae) in mixed conifer forests in the Sierra Nevada (10 pts): Which tree suffers most heavily from attack by cone beetles (Conophthorus spp.)? (2 pts) Name two trees that do not have tree-killing bark beetles (2 pts) From looking at the bark, how would you distinguish active galleries of ambrosia beetles from those of phloem-feeding bark beetles? (2 pts) note differences in host trees, maternal galleries and larval galleries of the mountain pine beetle and the western pine beetle (4 pts) 13) Answer the following questions about any one of the three main invasive forest insects that we discussed in class (10 pts): Give its name and the host trees that it attacks (2 pts) What damage does it cause and why? (4 pts) What efforts have been made to control it using natural enemies? (4 pts)

3 14) Answer the following questions about defoliators (10 pts): Name a specific defoliator and the trees that it is associated with? (2 pts) How would you classify the outbreaks of eastern spruce budworm, and what is the main factor that allows the development of outbreaks? (4 pts) What percentage of defoliators show population cycles, and what exogenous and endogenous factors could drive population cycles? (4 pts) Short answers 15) Define the term endophyte and give an example of one. (2 pts). 16) What is a cryptic species complex? Given and two examples of fungi that would qualify as one. (3 pts) 17) What limits the spread of hypovirulence causing virus in Chestnut blight (Cryphonectria parasitica), and how have people attempted to circumvent this problem? (2 pts). 18) What are extractives? what part of the wood has the highest concentration of these? (2 pts) 19) What are the three steps (or barriers) to successful invasion for all exotic organisms? (3 pts) 20) What are the four groups of natural enemies of forest insects? (4 pts) 21) Name two insects that are rapid colonizers after fire (2 pts) 2007 Final 1) Insects, plant pathogens, and plants have all been introduced to new settings via human commerce. a) List five specific examples of such introductions (five total with at least one insect, one pathogen, and one plant) (5 pts): b) For each of your examples briefly discuss the impact on plants or ecosystems and, if relevant, discuss the impact on the fire regime (15 pts). 2) Given a densely stocked, mid-elevation mixed conifer forest in the Blodgett area with ponderosa pine, sugar pine, white fir, Douglas-fir, incense cedar, and black oak in approximately equal numbers in the overstory answer the following questions:

4 a) Which species are likely to be in the understory and why? (2 pts) b) Over the long-term, which one of these species will be difficult to maintain at the current level under any reasonable management regime and why? (2 pts). c) Name two diseases that would increase in severity if white fir density increased substantially and explain why host density matters with these diseases. (4 pts) d) If you used prescribed fire to reduce the fuel loads and thin the understory, what insects would likely colonized the dead and surviving trees and which tree species would be most and least susceptible to insect attack? (6 pts). 3) Answer the following questions about blackstain, Leptographium wageneri, in ponderosa pine: What types are habitats or conditions are most conducive to this disease? (4 pts) What parts (be specific) of the tree does the disease infect, what does the fungus do in these infected parts, and how is this similar or different from blue stain fungi? (6 pts) How does the disease spread within sites and between sites? (2 pts) 4) What are the six feeding groups that forest insects belong to? For each feeding group provide an example insect and indicate what tree you would expect to find it on. (12 pts) 5) What are the three most important genera of bark beetles in California? Note for each genus whether it is monogamous or polygamous, and explain the significance of polygamy versus monogamy in scolytids. (10pts) 6) Why are conifer forests more prone to tree mortality from insect defoliators than hardwood forests? Provide an example of an important defoliator on each of the following types of tree (a) western fir and spruce forests, (b) Douglas fir and white fir in California, (c) lodgepole pine in California, (d) oaks in California, and (e) incense cedar in California. (10pts) 7)What types of treatments may be possible surrogates for wildland fire? How would these treatments be similar or different than fire? (6 pts). 8) Fire histories can be created using point and area frequency methods. Briefly describe both methods and give a forested ecosystem that is appropriate for each method. (6 pts).

5 9) Contrast the ecological affects of a large (3000 acre) high intensity (flame lengths 50 feet) wildfire in a coastal Bishop pine forest versus mixed conifer forests in a Sierra Nevada. (6 pts) 10) Fire can impact plants (in terms of producing injuries relating to death) in 3 broad categories, list them and give plant characteristics that have evolved to reduce the chance of death. (6 pts) 11) Answer all of the questions for 2 of the following 3 papers listed below (a,b,c). If you presented the paper you must answer omit it. a) From the Taylor & Carroll paper on mountain pine beetle outbreaks in British Columbia, answer the following: At what age does lodgepole pine become particularly susceptible to beetle attack and why (4pts)? Explain how fire history has influenced the current percentage of susceptible trees in the forests (4pts)? Roughly what acreage of forest has been affected by the current outbreak, and when is it expected to decline (2pts)? b)from the Slaughter and Rizzo paper on root disease and Yosemite Valley answer the following: Which root disease or diseases are the biggest problem in Yosemite, and what hosts are affected? (4 pts) (Slaughter and Rizzo paper) How has fire suppression contributed to these root disease problems (2 pts)? (Slaughter and Rizzo paper) What management actions, other than fire suppression exacerbated these root disease problems and how? (4 pts) c) From the Keeley paper on alien plants and fire management Give two examples of alien plants that Keeley mentioned and for each briefly discuss their interaction with fires and fire management (6 pts) According to Keeley will reestablishment of the pre-european fire regimes solve or exacerbate these problems and why? (4 pts). 12) Short answers What are the three responses that define the death rate of natural enemies? (3pts) What is the difference between a gradient and eruptive population outbreak and what type of feedback (density dependence) is associated with each? (3pts)

6 Which has the faster rate of nitrogen release on the floor of a hardwood forest, insect frass or fallen tree foliage? (2pts) Other than color, how can you tell a brown rot from a white rot and what is the real difference between the two? (4 pts) Give an example of a fungus that causes a brown rot and briefly describe what it does or where you would find it (i.e., is it a pathogen or saprobe and what trees would they colonize). (2 pts). Give an example of a fungus that causes a white rot and describe what your example fungus does in the forest (i.e., is it a pathogen or saprobe and what trees would it colonize). (2 pts.) Name a host that could be infected by a Phoradendron species, and explain how this pathogen is dispersed. (2 pts) Name a type of forest pathogen that is especially important at geographic edges of their host's range ( 2 pts). Name 3 tree species that associate with ectomycorrhizal fungi (3 pts) Wildland fires are influenced by three interacting classes of variables, what are they? (3 points): List and briefly define the new and old wildland fire terminologies used in the United States? Why was the terminology changed? (4 points) What are 3 common prescribed fire ignition patterns? Which would you use for a low intensity fire? Which for a high intensity fire? (5 points) What weather variables are critically important regarding wildfire behavior? ( Final 1. Describe the sequence of death of a mature pine species using combinations of fire, insects, and disease. Be as specific as possible. A) First select of species of pine that is being killed, describe where its living, which species of trees would be its likely competitors in this setting, and how shade tolerant it is relative to these competitors. ( 6 pts) B) Give two common diseases that might have weakened the tree, indicate where they are located in the tree, what their effect on the tree is, and whether the competing trees species that are listed in part A are likely to have them. (6 pts.)

7 C) Give two common insects that might have weakened the tree, indicate what they feed on, what their effect on the tree is, and whether the competing trees species listed in part A are likely to have them. (6 pts.) D) Describe two different fire scenarios that could kill this tree either directly or indirectly. Which, if any, of the competing tree species (from section A) would be more likely to survive. What type of fuels and weather conditions would you need for each type of fire you describe? (6 pts) E) As the tree is dying what specific insects will arrive?, in what order? and what parts of the pine will be attacked? (6 pts) F) What secondary pathogen(s) could arrive and how? (4 pts) G) Give examples of two wood decay fungi that you might expect to colonize the dead pine and describe the type of rot they would cause (4 pts) H) Give two examples of insects that would colonize the dead wood. (2 pts). 2. Answer 3 of the following 4 questions, and if you lead the discussion on one of these papers you have to exclude that one. (30 pts) A) How do grasses change fire regimes (give some specifics here), and how do these change lead to a positive feedback to create a system conducive to more grass? B) List three hypotheses that Niemela and Mattson put forth to explain why more European insects have invaded North America than visa versa. For each hypothesis briefly discuss evidences that supports or contradicts the idea. C) What are the main root disease problems (be specific) in Yosemite Valley? And according to Slaughter and Rizzo how have human actions (plural) exacerbated these? D) Explain the behavior of Phellinus weirii and fire regime with respect to mountain hemlock, Pacific Silver fir, Lodgepole pine in Oregon forests as discussed in the Dickman chapter. 3. List three canker diseases, for each give the host, and the environmental setting where the disease would likely be important. (10 pts) 4. Diagram the disease cycle for Red Band or Brown Spot blight, indicate the hosts that are involved, and the environmental conditions necessary for a serious

8 disease problem to develop, and explain the main differences between needle blights and needle casts. (10 pts).

9 5. Briefly note the three steps necessary for successful invasion of an introduced insect, the three main sources of materials that carry invasive forest insects into the country, and the four management options that can be used to minimize the damage potential of these invasions. (10 pts) 6. Consider the forest insects that are associated with white fir in the Sierras. Give examples of a cone insect, two defoliators, a bark beetle, and two woodborers. Which two would you consider to be the most damaging and why? (10 pts) 7. You are working for the US Forest Service in the El Dorado National Forest in the Sierra Nevada. You have been asked to produce a plan to reduce potential fire behavior in a 5000 acre area of mixed conifer forests. This forest area has been partially harvested 3 times over the last 50 years and fire suppression has been in place for 100 years. What fuel components and forest structures would you propose to modify? Which components are the most critical? Explain (10 points) 9) Discuss the advantages and disadvantages for the installation of shaded fuel breaks (Defensible Fuel Profile Zones) versus Strategically Placed Area Treatments (SPLAT s). In which settings do each of these landscape fuel modification methods make the most sense? Why? Would you expect the dispersal of invasive species to me different in these 2 strategies? Why or why not? (10 points) Short answer: A host for Swiss needle cast and the region where the disease is native. (2 pts) Why is lignin difficult to digest? and how is it digested? (2 pts) An example of a common heart rot of true firs? and a different common heart rot of hardwoods (oak for example). (2 pts) Two ways Dutch Elm disease is transmitted to uninfected trees. (2 pts) Two rusts of pine other than white pine blister rust. (2 pts) Four different ignition sources for forest fires in western North America? (4 pts) Three interacting classes of variables that determine wildfire behavior. (3 pts) What are 3 common prescribed fire ignition patterns? Which would you use for a low intensity fire? Which for a high intensity fire? (4 pts) Incident Commanders must be aware of many issues during a prescribed fire, list 5 of these issues. (5 pts)

10 Name the two most important invasive forest insect pests to have arrived in the U.S. since (2 pts) What are the two responses that in combination determine the death rate imposed by natural enemies on their host populations? (2 pts) Which of the above factors is thought to be responsible for generating cycles in the population abundance of southern pine beetle and gypsy moth? (2 pts) Which two groups of forest insects require the assistance of microbial symbionts to assist in the acquisition of a suitable supply of food? (2 pts) Final Spring 2004 In your blue books or paper, make sure you write your name and the number and letter of each question you are answering. 1) Explain how three agents: insects, fire, or disease could facilitate four of the five processes listed below. Discuss: 1) the relative importance of all three agents for each process, 2) give a total of two specific examples for each process (not two for each agent for each process), and 3) explain how your examples work to facilitate the given process. (40 pts) For example If the process was "maintenance of monocultures", you might say that fire is the most important of the three agents, followed by insects and disease. You could cite Bishop pine and Lodgepole pines fire regimes as two examples, and then go on to explain how closed cones, and dense fuel loads interact with crown fires to maintain these monocultures. Your answer to each process is worth 10 pts, so some depth is expected. Select four of five to answer: a. Maintenance of geographic ranges b. Maintenance of species diversity c. Selection for genetic diversity within species d. Maintenance of forest structure (i.e., species composition and stocking levels) e. Driving force in removing pioneer species in succession 2) Answer any 2 of the 3 following questions

11 a.(20pts) Discuss five different adaptive features of insects indicating how they may account for the success (species richness and diversity of lifestyles) of this group of organisms. b.(20pts) Discuss four different mechanisms that may contribute to the population cycles of forest insects. c.(20pts) Provide brief details of the biology of a named insect from each of five different feeding groups that you would expect to find on pines in the Sierras 3) In mid altitude west-side Sierra mixed conifer forest, mortality is occurring in Ponderosa pine, while all other trees seem to be unaffected. The mortality is an a hectare- sized area and seems to have occurred over many years. (10 pts) Which insect or disease would you expect to be the primary causal agent or agents. Explain your reasoning, and describe any other information or observations you might want to obtain from the site to confirm you diagnosis. Name three other insects or diseases that you might expect to find as significant secondary that would contribute directly to the mortality. 4) Name five different types of natural enemies that you would expect to find associated with conifer sawflies, with very brief explanation of the form of the interaction. (10pts) 5) Fire and fire surrogates treatments have been proposed to reduce fire hazards and reintroduce basic ecosystem processes into Sierra Nevada mixed conifer forests. Compare the similarities and difference of prescribed fire alone, mechanical alone, and mechanical followed by fire treatments in terms of the impacts on potential wildfire behavior and effects, forest insect dynamics, pathogen interactions, and economics. (20 points) 6) Contrast the ecological affects of a large (1000 ha) high intensity (flame lengths 50 feet) fire in a Bishop pine forest versus in a Sierra Nevada mixed conifer forest. (10 points) 7) Give two examples of the way in which introduced plants have altered fire regimes and explain the impacts these changes have had on plant community structure. Be specific about how the components of the fire regime that changed and these changes fire behavior. (10 pts)

12 8) Short answers (2 pts each) a)the primary root disease responsible for mortality in Yosemite (be specific) b)the host on which white pine blister rusts sporulates in the summer c)a native rust fungus that attacks pine d)what is a hypersensitive response e)two primary hosts of the S strain of Heterobasidion. f)two diseases that involve insect vectors. 9) What are the three approaches to biological control of forest pests and which is the most commonly used approach in forest ecosystems (4pts) 10) What are the three features of the mountain pine beetle that make it an aggressive tree killing pest (3pts) 11) Give the names of the four principle insect groups that are attracted to fire damaged trees (4pts) 12) Give the names of two important insect pests of seed orchards (2pts) 13) What is the old and new wildland fire terminology? Why was this changed about 3 years ago? (5 points) 14)What weather variables are critically important regarding wildfire behavior? (3 points) 15) The President recently signed the Healthy Forest Restoration Act. It proposes thinning as the major answer to reducing fire hazards in millions of ha of western forests. What do you think of this idea? Be specific. (10 points) 16) What are 3 common prescribed fire ignition patterns? Which would you use for a low intensity fire? Which for a high intensity fire? (3 points)

13 Final Spring 2003 In your blue books, answer any 3 of questions 1 through 4. Clearly indicate the number of the question you are answering and be sure to answer all parts of each question selected. 1) (20 pts) Given a mixed conifer Forest in the mid Sierras answer the following questions: A) Name the six dominant tree species? B) How has fire suppression changed the composition the density of these forests? explain briefly both the current pattern and the processes that produced it. C) Discuss three pathogens that have probably become more common or have an increased impact in these fire-suppressed forests, and discuss the ways in which the changes induced by fire suppression have increased the importance of these pathogens. D) Discuss three insects that have become more common or have an increased impact in these fire-suppressed forests, and discuss the ways in which the changes induced by fire suppression have increased their importance. E) How has the behavior of fire changed in these forests as a result of fire suppression? and what factors directly effect this behavior. F) Discuses two ways that the process or success of tree regeneration changed in fire suppressed forests. 2) (20 pts) Select two of the following three goals and discuss the problems that make these goals difficult to achieve and the options available for achieving them. a) Reducing the impact of introduced pathogens and insects, b) Reducing risk of catastrophic fire in our current forests, c) Restoration of plant communities in Yosemite Valley, 3) (20 pts) Select two of the following three large severe fires : 1) Pt. Reyes, Mt. Vision fire 2) Yosemite, Foresta fire

14 3) Colorado, Hayman fire Now answer the following questions about them: i) What are the dominant species in the community involved. a. Were these fires typical of the fire regime for the community type? if not describe that regime. b. Is the pre-fire community likely to regenerate? if so, how? And if not, why not? 4) (20 pts) What are four possible factors that could predispose ponderosa pine in the Sierra Nevada to attack by bark beetles? List the potential primary attackers of the tree and the important secondaries. Give the sequence of their arrival at the tree. You may use common, scientific or family names but be as specific as possible. Answer questions either question 5 or 6 in your blue book 5) (10 pts) Discuss at least two possible explanations for why more exotic pests from Europe invade North America than vice-versa?. List three important exotic forest insect pests in North America (common or scientific name). 6) (10 pts) Define biological control. Give an example of a mass rearing and release program in forestry. In your opinion, what is the best biological control approach in forestry? 7) Short answer (fill them in below) (1 pt) Name a pathogen of Douglas-fir that is common in foreign plantation settings. (3 pts) Name a disease where a hypovirulent double-stranded RNA virus effects the virulence, explain how the virus spreads, and what limits this spead in a fungal population. (3 pts) Name three primary hosts of the S strain of Heterobasidion annosum (2 pts) Name two trees that you would not be hosts for dwarf mistletoe (3 pts) Name three introduced forest pathogens (3 pts) Name three trees or shrubs that form ectomycorrhizal symbioses. (3 pts) Name the three fundamental variables that influence fire behavior (5 pts) List the components that are used to describe a fire regime

15 (5 pts) list 5 issues that Incident Commanders must be aware of (6 pts) List 3 common ignition patterns used for prescribed fire and indicate which would be used for low intensity fires, high intensity fires, or both. (2pts) Give two characters that distinguish the arthropod subphyla Chelicerata from Mandibulata (3pts) Give an example of a chelicerate arthropod that can become a pest of trees in forests or plantations. Under what circumstances do these organisms become pests? (4pts) Give the common, scientific or family name of the four principal insects or insect groups that are attracted to fire damaged trees. Final 2002 I) Importation of green logs is considered from Korea, and as part of the risk assessment a list of known insect and disease problems in Korean forests is presented. The study concludes that the risk is miminal because most of insects and diseases are not serious pests, and those that are, have already been introduced into North America. Discuss the three glaring errors in this assesment, and include specific examples of introduced insects or diseases to illustrate your points. (20 pts) II) Answer one of the following two: A) In a situation where you have an overstocked stand of 50 year old white fir in the western Sierra, what kind of insect and disease problems would you expect to encounter with these trees. Give two diseases and six different insects in five families and discuss the sequence of their arrival. Give the common or scientific name of the insects and be sure to indicate which family they belong to (20pts.). B) In a prescribed burn in a west side Sierra mixed conifer stand that is uneven aged with both large and small trees, what insects might be found following the burn. Give the common or scientific name and associate these insects with the tree species that they would be found on. Be sure to indicate the sequence and location of attack by the insects. (20pts.). III. Answer one of the following two: A. You are a resource manager at Yosemite National Park and are charged with developing prescriptions to re-introduce fire into this ecosystem. Fire suppression has occurred for the last 70 years and this has produced high fuel loads and forests that are dominated by shade tolerant conifers. Your objective is to lower the fuel levels and gradually return the forest to a Pine/oak dominanted woodland with a moderate stocking level. What types of treatments do you propose? What types of insect, disease, or plant community interactions are possible in response to these treatments? (20 pts)

16 B. You are the fire management officer on a large area (50,000 acres) of US Forest Service land in a western Sierran mixed conifer forest. The area is diverse with a small community near the center. Your goals are to maintain a mixed conifer forest, to produce timber, and to reduce fire risk to the town. What would you propose? and what are the potential problems you could envision. Be specific with respect to types of treatements and when possible mention species by name. How would you deal with such a large area? _IV. Answer two of the following 3 questions: A) Give two possible explanations of why more exotic pests from Europe are successful in North America than vice-versa and give the common or scientific names of three important exotic forest insect pests. (10pts.) B) Describe two ways in which introduced grasses have altered fire regimes, and give specific example of locations where this has been important, and effects this has had on plant communites and ecosystem function (10 pts). C) Briefly describe the interactions between Mountain Hemlock, Lodgepole pine, Pacific Silver Fir, Phellinus weirii and Fire regime (10 pts) V. Answer any 10 of the following 12 short answer question. Draw a line through the two that you omit, otherwise the first 10 will be graded. Each are worth 2 pts. You find a small patch of white-fir saplings in the understory and when you examine the lower limbs you notice that the needles from 3 years ago are missing on most of them, even though older and younger needles are present and appear to be healthy. What happened to the year three needles and why did it only effect a single year? Young incense cedars have blackened bark, but none of the surrounding trees appear to be charred. What is the likely cause? What is the essential difference between a white rot and a brown rot? Give an example of a species for each. Give an example of a fungus that spread primarily by mitotic (Asexual) spores, and one that spreads primarily by meiotic (sexual) spores). Give two important forest insect pests (common or scientific name) of seed orchards Give two important forest insect pests (common or scientific name) of urban forest Give two important forest insect pests (common or scientific name) of seedlings in a nursery Give two important forest insect pests (common or scientific name) of 10 year old pine plantation

17 Give an example of a biological control program and explain it briefly. Give an example of a pheromones or semiochemicals control program and explain it briefly. What are the components of a fire regime? Why is this concept important? What are the common firing patterns used in prescribed fires? How are they different? Final Fall 2000 Answer one of the following two: (20 pt) Briefly describe the present plant communities in the Liminatour road area of Pt. Reyes and discuss how the relative frequency of the dominant species would be affected by i) a 5-year fire return interval of low intensity ground fire ii) a 200-year fire return interval with high intensity crown fire. For each scenario discuss the ways in which the major insects and diseases that would interact with these changes. or Briefly describe the present plant communities in the Lake Tahoe basin and discuss how the relative frequency of dominant species would be affected if i) total fire suppression was maintained, or ii) a program of mechanical thinning (i.e., logging) and prescribed understory burning was instituted. For each scenario discuss the ways in which the major insects and diseases that would interact with these changes. Name the three most important Genera of bark beetles, and name the common or scientific name of two outbreak species of defoliators. Now contrast the differences between defoliators and bark beetles with respect to impact on stands and their interaction with disease and fire. (20 pt) Define and contrast Biological Control and Integrated Pest Management. (10 pt)

18 Discuss four adaptations to fire exhibited by plants. Include in your discussion the appropriate name for the adaptation, the tissue or tissues being protected and how the adaptation helps the plant to survive and or benefit from fire. Give specific plant examples whenever possible. (16 pt) \List five examples of introduced pathogens or insects that have had a dramatic effect on forest communities. For each example give the primary host or hosts in its new setting, the way it disperses, and if known, give its place of origin and discuss how it was introduced. (20 pt) Short answer: Given a gene-for-gene system list two pathogen genotypes that could infect a host plant with r 1 r 1, R 2 R 2, R 3 r 3, r 4 r 4 (2 pt) Which plant community is likely to have the higher ph soil, a mixedconifer forest or grassland? How does soil ph change following fire in these communities? (2 pt) List four atmospheric products of fire. (4 pt)

19 Briefly discuss potential fire effects on water quality in a watershed (3 pt). (5mins) True or False: Biomass, flowering and seed production decrease following fire. (1 pt) Organic matter content is a property of soils that can be altered by fire. (1 pt) The fruitbody of Heterobasidion is an example of a coral fungus 1) Answer either A or B: (25 pts) Final 1999 A) Given a bishop pine forest in the Pt. Reyes area, discuss two plausible scenarios involving insect, fire and disease interactions that could push it toward A) a coastal scrub community in one case and B) a Douglas-fir forest in a different case. Be as specific as possible in terms of plant species and recolonization strategies that are relevant, and insect, diseases and fire regimes involved. B) Given a mixed conifer forest at about 4000 ft. on the west side of the Sierras with a high component of white fir and incense cedar discuss two plausible scenarios involving insect, fire and disease interactions that could push it toward A) a pine dominated forest and B) a shrub dominated community. Be as specific as possible in terms of plant species and recolonization strategies that are relevant, and insect, diseases and fire regimes involved.

20 2) Discuss how soil properties and the soil microbial community may be altered by fire. In forested areas of the mixed-conifer, what are the major management concerns with respect to fire and soil properties? (10 pts) 3) Select a western forest type and discuss fire and forest conditions that are likely to result in the following landscape scale patterns: (18 pts) a. large fires in spatial extent, but with small patch sizes b. medium size fires, medium size patches c. small fires in spatial extent, large patch sizes 4) Briefly describe the life cycle of an Ips bark beetle. Which sex attacks first, describe the egg gallery, what parts of the tree are attacked, and what associated bark beetles would you expect to find and where on the bole of the tree. (10 pts,) a b What influence would fire have on these beetles? (2pts.) Discuss at least 4 interactions, positive or negative, that these beetles have with fungi. (8 pts.) Short answer: What is the difference between the way that "early-stage" and a "late-stage" ectomycorrhizal fungi colonize a tree. (2pts) Given a gene for gene system list two pathogen genotypes that could infect a host with the following genotype R1r1,r2r2,R3R3,r4r4. (2 pts) Give four examples of introduced species of pathogens or insects. (4pts) Excluding all of the introduced pathogens used in the above question give an example of two pathogens that often have their greatest effects outside the natural range of their hosts or in plantation settings. (2 pts) Give an example of fire synergism which shows that you understand the meaning of the term (2 pts). How does the amount of soil organic matter influence soil temperature during a fire (2 pts)?

21 Give the common or scientific name of one important hymenopteran and one lepidopteran forest defoliator. (2pts) Excluding Ips name two genera of bark beetles that are important in forestry and give the family to which each belongs. (4 pts.) Give an example of a successful biological control program in forestry, either the common or scientific name of the insect controlled. (2pts.) True or False (1 pt each): Standing-replacing fires are always high-intensity fires. Redwood stands are highly susceptible to crown fires. Final 1996 I. Answer either A or B but not both (12 pts) A) Assuming Siberian Logs are imported into this country and treated as currently required (i.e., debarked in Siberia and fumigated on the docks in North America within 8 weeks of arrival), name four specific types of insects or pathogens would you expect to survive this treatment, and briefly discuss why you believe each is likely to survive. B) In the Hemlock, Silver fir, Lodgepole pine ecosystem discussed by Dickman (i.e., the paper you read in the Can. J. Bot.) what predictions would you make for tree species composition given the following twofire return intervals. For each discuss how these plant community changes are mediated through specific insects and disease interactions. 1) total fire suppression (assuming this is possible); or 2) a fire return interval of 100 years. II. For 2 of the following 3 statements (i.e., omit one), state whether each is true or false and then defend your answer. (12 pts) a) Bishop pine that survived the Pt. Reyes fire are less likely to produce seedlings than those which were killed directly by the fire. b) Given the type of fire required for Bishop pine to reproduce it will not be possible to manage for this species in Pt. Reyes. c) The salvage logging rider is a reasonable way to deal with the legitimate problems of rapidly removing dead or dying trees while they still have commercial

22 value. III.. Gypsy moth, chestnut blight, Dutch elm disease, and white pine blister rust have been introduced into North America, and pitch canker has been introduced into California. Select two of these organisms and briefly describe their biologies, the effects they have had on the forests in which they are active, and their likely interactions with these forests over next 100 and 10,000 years. (12 pts) IV. Answer one of the following two questions: (10 pts) A) Contrast the skeletal, respiratory, excretory, circulator, and digestive systems of insects and humans. B) Discuss five attributes of insects that contribute to their diversity and ubiquity in terrestrial ecosystems. V. Select a setting from one of the fieldtrips and discuss at least 6 interactions among tree species, humans, insects, rodents, pathogens, mutualistic microbes, other plants, or other biotic or abiotic components of the ecosystem. Which if any of these interactions are likely to affect forest composition. (12 pts). VI. Contrast the fire regimes of Pseudotsuga menziesii and Pinus ponderosa. Which species is more negatively affected by fire suppression and why? Use at least one of our three field trip sites to illustrate this discussion. (12 pts) VII. Name one specific effect of fire on each of the following: vegetation, soil properties, hydrology and atmospheric chemistry. Be sure to include whether the effect is short or long-term temporally. (12 pts) Final 1995 (early version) 1) This course has emphasized the interactions between insects, pathogens, fire, humans, and forests. Select a specific site from one our field trips in which all of these factors played a role in creating the present forest. Describe in detail what the specific factors were, how they interacted, and project ahead 100 years to what the forest at this site might look like. (50) 2) When relevant in the questions below give examples of specific plants, insects, disease, fire regime, and fire characteristics. (25) Describe a situation in which an insect problem would be increased from fire. Describe a situation in which an insect problem would be reduced from fire.

23 Describe a situation in which an disease problem would be reduced from fire. Describe a situation in which shrubs would be increased from fire. Describe a situation in which shrubs would be reduced from fire. 3) From the general papers handed out at the beginning of the course and from what you have learned since, what is the prognosis for maintaining of the worlds forests? Give your specific reasons for being either optimistic or pessimistic, and provide recommendations that would improve the chances of maintaining healthy forests. (25) 4) Classify and discuss insects in terms of the type of damage they cause on a tree, and give a specific example of an insect for each type of damage you discuss. 25 pts. 5) Give an example of a needle cast, a needle blight, and needle endophyte, contrast their life cycles and their impacts on forest systems. (25 pts). 1. Fire components (10 pts) 1994 final questions A) Describe fireline intensity and fuel consumption (verbally and mathematically) B) Which will have the greatest direct effect and why on: i) the forest floor? ii) the crown of a 100' tree with the lowest branch no closer the 60' from the ground? iii) the base of the tree within the duff layer? 2) Synthesis of Sierra forest systems (20 pts.) A) Given a mixed conifer forest on the west side of the Sierras (A) such as the one that likely dominated the Blodgett area before 1850, give a set of plausible human actions, insect, fire and/or disease interactions that could

24 have driven the community in each of the directions indicated over a time scale of less than 150 years (i.e., arrows 1,2,3). Be specific about the fire regimes and species of insects or pathogens involved. (12 pts) B) Discuss four major insect or disease problems that would have a greater impact in communities B and/or C than in the original community A, and discuss your reasoning for each. Be specific in your examples. (4 pts) C) Presumably regeneration of the mixed conifer community (cycle 4) was a common pattern in the past. Discuss two reasons why this cycle may be difficult to restore without human intervention in the present. (4 pts) 3) Briefly discuss the biochemical difference between a white rot and a brown rot and the ecological impact of this difference. Then list one example of a fungus that causes each type of rot (a total of 2 fungi). (5 pts) 4) "Insects are the earth's most varied organisms. Almost exactly half (50.8 %) of the species of living things are insects. They occur in a enormous variety of habitats" (from Daly et al.) Describe 5 adaptations of insects that contributed to their success and allowed them to occupy these diverse habitats. (5 pts). 5) Short ecological mysteries - Answer 5 of the following 6 (i.e., omit one of your choosing); only a short answer is required for each. (10 pts. total) As you walk down a gentle slope dominated by a lodgepole pine monoculture toward a meadow at the bottom of the hill you notice that a high percentage of trees near the meadow are infected with stalactiform rust, while the trees at the top of the hill were free of infection. What could explain this pattern? (2) In a different lodgepole pine forest the majority of the trees have large galls caused by Western Gall rust, and almost all of these are at about head height. Why is there such uniformity in height? (2) A single seed of dwarf mistletoe is carried long distance by a bird and successfully establishes an infection in an area where no other members of this species of Arceuthobium exists. It is safe to say that this infection will never spread to other trees or even to other branches of the same tree. Why? (2) You enter a new plantation with 10 year old Douglas-fir and notice that most of last years needles are missing from the lower branches, yet this years needles, the needles from three and four years ago, and needles of all

25 ages on the upper branches are fine. What could explain this pattern? (2) You enter a naturally -regenerated 20 yrs-old ponderosa pine stand. The average diameter of the trees is 25 cm. You see a small group of trees (10) with yellow foliage and no green needles. What is the most likely agent or agents that have caused these symptoms. (2) As you stand on a beach on the west shore of Lake Tahoe and look back at the hills behind you, you see large areas of grey-colored (i.e., dead) trees. The forest is comprised primarily of white fir. What agent is likely to be responsible for this mortality and what human actions lead to the composition of this forest. (2)_