Chapter5_KEY

What is lichen?

A symbiotic relationship between fungi and algae.

How do lichens contribute to soil formation?

They attach to rocks and trees and help in the formation of soil.

What role do mosses play in northern coniferous forests?

They are important for water retention and nutrient cycling.

What is a herb in the context of northern coniferous forests?

A non-woody dicot; angiosperms that are usually sparsely developed.

What are two benefits of conifers retaining their needles?

1. Photosynthesis during a short growing season; 2. Nutrient conservation.

What adaptations do conifer leaves have to reduce moisture loss?

Needle-like leaves with a thick protective layer and sunken stomata.

What provides an environment for shade intolerant species in forests?

Tree fall gaps.

What is the problem affecting white cedar regeneration?

Heavy browsing by deer is preventing cedar recruitment.

How old are the old growth forests of Itasca State Park?

200-250 years.

Why were the original forests of Itasca a mosaic of red and white pine?

Dry sites were prone to fire, suppressing white pines, while wetter areas supported them.

How have perceptions of forest fire roles changed in the last 45 years?

Fires are now understood to be integral to forest ecosystems.

What are some types of evidence for the history of forest fires?

Tree rings and sediments from charred wood at the bottom of ponds and lakes.

List three reasons that pines survive and reproduce after fire.

1. Thick, fire-resistant bark; 2. Resin to seal wounds; 3. Tall trees withstand ground fires.

What effect does prescribed burning have in managed pine ecosystems?

Fire prevention policies can hurt forest maintenance by preventing necessary ecological processes.

How does aspen reproduce?

Aspen often reproduce asexually through clones from roots or via seeds.

What limits the perpetuation of mature aspen forests?

Shady conditions inhibit seed germination and promote fungus growth that kills young seedlings.

What are the two major limiting factors of northern coniferous forest productivity?

Low nutrient levels and cold climate.

What are the productivity and biomass differences between early and late successional stage forests?

Early successional: High productivity & low biomass; Late successional: Low productivity & high biomass.

How does the worm parasite P. tenuis affect deer and moose?

It has little impact on deer but is fatal to moose.

What is the social structure of a timber wolf pack?

They live in packs led by an alpha male and female, with non-reproductive members helping hunt and rear young.

How can yellow-bellied sapsuckers be recognized?

They make evenly spaced holes in tree trunks to obtain sap.

Why are there more bird species in a 60-90 year forest stand?

Higher structural diversity allows for more niches.

Why do ruffed grouse need different habitats?

Different habitats meet their food and protective cover requirements.

How do ruffed grouse avoid winter predation?

They burrow into deep snow to evade predators.

What changes have occurred in northern forests over the last 100 years?

Pine forests have been replaced by maple-basswood-birch forests due to logging and fire regime changes.

What are three perspectives that will define future changes in northern forests?

1. Economic value; 2. Aesthetic value; 3. Ecological values of soil and water conservation.