This exam is an opportunity to demonstrate your abilities to think creatively and to integrate all the various topics we have covered in both quarters thus far. Take this as an opportunity to shine and really show me what you know. While you need to give me enough details to fully support your answer, don’t give me extraneous ones. Please try to limit your answers to one side of a page for each question.

1. Clearcuts most likely will continue to be a favored method of harvest.
1. Outline the ecological and economic arguments in favor of clearcuts.

Economic arguments--The economies of scale and harvest favor clearcutting. Harvesting all the trees with one entry into the forest gives the highest rate of return with this harvest method. Fewer roads are needed per volume of timber harvested so this decreases costs. Also makes replanting the trees much easier and less costly. No high-grading so forest that grows back will be valuable. Safer for woods workers so it will decrease L & I claims and costs.

Ecological arguments--Clearcuts mimic natural disturbances, like fire, windthrow, disease, that create openings in the forest canopy. There are a number of shade-intolerant species that will not regenerate under a closed canopy, for example Douglas fir on the west side of the Cascades. This will have the net effect of increasing the biodiversity of the entire forest. Clearcuts also increase the forage for large mammals such as deer and elk. Fewer roads are needed per volume of timber harvested so this decreases erosions associated with roads and road building. Can benefit the forest by removing and/or isolating diseased trees to control/minimize impacts of diseases and pests.

2. Outline the ecological and economic arguments against clearcuts.

Economic arguments--Loss of other uses for forest e.g. recreation, grazing etc.

Ecological arguments--There are a number of different levels that you could answer this on. The basic level is from a system view; removal of all that biomass is going to disrupt the local ecosystem and displace all the animals and understory plants in the forest. A number of different cycles within the forest will be impacted--the hydrologic cycle, the nitrogen and carbon cycles--as well as changes in the physical characteristics of the forest. Increases the probability of invasive species.

Hydrologic cycle--removal of the forest will decrease the amount of transpiration, will decrease percolation, increase surface runoff, all of which will cause greater peaks in the surface rivers. Erosion and landslides will increase both in the former forest, as well as along the rivers and streams. In some areas, trees harvest water vapor from the atmosphere and this ability would be lost.

Nitrogen cycle--Clearcuts remove a great deal of nitrogen from the site, decreasing future productivity until those nitrogen levels can be replaced. Nitrogen is removed in the trees, by burning the slash and through removal of the trees which could take up any nitrogen released by decomposition of the foliage. Without plants to take up the N, it will converted to NO₃^- which will be rapidly leached from the soil due to its negative charge.

Carbon cycle--removal of the biomass will decrease the amount of large wood debris in the forest. LWD serves as a refuge and habitat for fungi, small mammals, as well as an important reservour of water in the dry season.

Physical changes--the most obvious one is the increased solar exposure which can dry the soil, warm it up and increase the rate of decomposition of organic matter. This can have long-term consequences on soil fertility due to decreased organic matter. This will also change the types of plants that will be able to survive and colonize the clearcut. The new forest will be all the same age which can increase the impact of diseases and pest outbreaks.

3. Discuss how you might plan a clearcut to minimize the negative effects you described above.

Use site-specific management planning. Limit the size of the clearcut so that it more closely mimics a small disturbance. Leave large woody debris and most of the understory. Leave sufficient buffers to protect streams from erosion. Leave/create coarse woody debris, standing snags. Leave all foliage and branches to decay. Leave some green trees and all shrubs to retain nutrients and minimize nutrient loss from site.. Replant immediately and actively manage for several years to insure survival of the trees. Use an overhead logging cable system to reduce soil compaction.

2. The forest surrounding campus formerly was old-growth Douglas fir/hemlock and following logging is now second growth. What types of restorative ecological management measures could be implemented to "restore" it to old growth characteristics as rapidly as possible?

Do background research to find out what the plant community was in the past. Survey current forest to know where you’re starting. Some thinning and small clearcuts could be done to increase the age-diversity of the forest. Minimize any removal of trees, leave to develop into snags, nurse logs etc. Manage for biodiversity. Leave/create coarse woody debris, standing snags. Remove all non-native species. Try to minimize/manage human impacts throughout the forest. Let time do its work.