SAF Forest Ecology & Silviculture 2 — Questions and Answers
Question 1: Which silvicultural system is most appropriate for shade-tolerant species like sugar maple and American beech that regenerate best under a continuous forest canopy?
- Clearcutting
- Shelterwood
- Selection system (Correct answer)
- Seed-tree method
Correct answer: Selection system
The selection system maintains a continuous canopy cover, creating the shaded understory conditions that shade-tolerant species require for successful regeneration.
Question 2: What is the term for the process by which pioneer species modify the environment to make it more suitable for later successional species?
- Facilitation (Correct answer)
- Inhibition
- Tolerance
- Climax replacement
Correct answer: Facilitation
Facilitation describes how early successional species alter soil, light, and moisture conditions in ways that allow later successional species to establish and eventually replace them.
Question 3: A forester observes that a recently harvested stand has regenerated primarily with aspen via vegetative sprouting from root systems. This regeneration mechanism is called:
- Epicormic sprouting
- Coppicing
- Root suckering (Correct answer)
- Layering
Correct answer: Root suckering
Root suckering occurs when new shoots arise from the lateral root system, which is the primary regeneration mechanism for trembling aspen (Populus tremuloides).
Question 4: In even-aged silviculture, the preparatory cut in a shelterwood system is designed primarily to:
- Remove all overstory trees to expose the seedbed
- Improve the vigor and seed production of retained trees (Correct answer)
- Release advanced regeneration already established in the understory
- Remove competing understory vegetation before planting
Correct answer: Improve the vigor and seed production of retained trees
The preparatory cut thins the stand to improve crown development, vigor, and seed production of the trees that will be retained to provide seed and shelter during subsequent cuts.
Question 5: Which of the following best describes the concept of 'forest floor' in ecosystem ecology?
- The mineral soil layer directly beneath the A horizon
- The accumulation of organic matter including litter, duff, and humus on the soil surface (Correct answer)
- The herbaceous and shrub vegetation growing on the forest ground
- The zone of maximum root density in the soil profile
Correct answer: The accumulation of organic matter including litter, duff, and humus on the soil surface
The forest floor consists of organic layers (O horizon) including fresh litter (Oi), fermenting material (Oe), and well-decomposed humus (Oa) lying atop the mineral soil.
Question 6: Beech bark disease results from a complex interaction between which two organisms?
- Nectria fungus and beech scale insect (Correct answer)
- Armillaria fungus and bark beetle
- Phytophthora oomycete and aphid
- Hypoxylon fungus and wood borer
Correct answer: Nectria fungus and beech scale insect
Beech bark disease is caused by the beech scale insect (Cryptococcus fagisuga) creating wounds that allow infection by Neonectria fungi, ultimately killing American beech trees.
Question 7: In forest mensuration related to silviculture, 'site index' is defined as the average height of dominant and codominant trees at what reference age?
- 25 years
- 50 years (Correct answer)
- 75 years
- 100 years
Correct answer: 50 years
Site index is conventionally defined as the average height of dominant and codominant trees at a base (index) age of 50 years, though some species use a base age of 25 or 100 years.
SAF Forest Ecology & Silviculture 2
Which silvicultural system is most appropriate for shade-tolerant species like sugar maple and American beech that regenerate best under a continuous forest canopy?