Tree Biology, Ecology, and Forest Management in Oregon

What is the primary function of leaves in a tree?

make up the canopy and help supply food and release oxygen through photosynthesis.

How do the branches of a tree support its structure?

support leaves, flowers, and fruits, and transport nutrients from the trunk to the canopy.

What role do roots play in a tree's growth?

take in water and nutrients from the soil, keep the tree stable, and store food.

What are the main layers of a tree from outer to inner?

Outer bark → Inner bark (Phloem) → Cambium Cell Layer → Sapwood → Heartwood → pith

What is the function of bark in a tree?

protects the tree and regulates moisture and temperature.

What does phloem do in a tree?

transports nutrients throughout the tree and eventually dies to join the outer bark.

What is the cambium layer responsible for?

supports new growth + produces and moves cells to create new layers in the bark.

What is sapwood and its function?

the new layers of the tree that transport water throughout.

What is heartwood?

supports structure + the central pillar of the tree, consisting of dead tree layers.

What is pith?

stores nutrients

What are the stages of a tree's life cycle?

Germination → Seedling → Sapling → Mature tree (producing fruits/flowers).

What is photosynthesis and its chemical equation?

the process by which plants convert carbon dioxide and water into glucose and oxygen: 6CO2 + 6H2O → C6H12O6 + 6O2.

What is cellular respiration and its chemical equation?

the process of converting glucose and oxygen into carbon dioxide and water: C6H12O6 + 6O2 → 6CO2 + 6H2O.

What is a dichotomous key used for?

used to identify tree and shrub species by comparing features.

What are the typical layers of a forest structure?

Canopy, understory, and ground layers.

What is found at the ground level of a forest?

Leaf litter and invertebrates that break down organic matter.

What defines the understory layer in a forest?

contains herbaceous plants and woody debris.

What is the significance of crown classes in a forest?

determine the amount of sunlight received by trees, affecting their growth.

What factors affect forest ecology?

Soil type, tree communities, regeneration, competition, and succession.

What is primary succession?

occurs on previously uninhabited land where pioneer species establish soil.

What is secondary succession?

occurs in areas that were previously inhabited, allowing for ecosystem recovery.

What are abiotic factors in a forest ecosystem?

Nonliving factors such as rocks, temperature, sunlight, water, and soil.

What are biotic factors in a forest ecosystem?

Living factors such as plants, animals, and microorganisms.

How does climate affect forest ecosystems?

determines which species can thrive and the productivity of the ecosystem.

What is silviculture?

the practice of managing and nurturing trees for growth and sustainability.

What is the purpose of forest health thinning?

To remove smaller, suppressed trees to reduce competition and promote healthier growth.

What is prescribed burning?

A technique using controlled fire to clear land and promote forest health.

What is single-tree selection in harvesting?

A method where individual trees are examined and chosen for removal, commonly used in uneven-aged stands.

What type of forests dominate Oregon?

Primarily dominated by coniferous trees like Douglas-fir, Western hemlock, Sitka spruce, and Ponderosa pine.

What is Group Selection in forestry?

A practice used to remove an entire group of mature trees to allow younger, suppressed trees to grow.

What is Shelterwood in forestry?

A method based on stand maturity where trees are gradually removed to encourage shade-tolerant species.

What does Clear-cutting involve?

The removal of all trees in an area to allow for regeneration and create an even-aged stand.

What tool is used to measure tree height?

Clinometer

What is the purpose of an Increment Borer?

To evaluate the age and volume of a tree.

What does Diameter Tape measure?

The diameter and linear dimensions of a tree.

How does forest health affect biodiversity?

Low productivity can hinder food and plant growth, negatively impacting both plant and animal biodiversity.

What practices can promote forest health and biodiversity?

Reforestation, replanting, and wildlife habitat creation.

How does forest fragmentation occur?

Through unhealthy forests that weaken over time, leading to increased vulnerability and decreased biodiversity.

How can air quality be affected by forest health?

Struggling forests with low photosynthesis or respiration can alter oxygen and carbon dioxide levels, harming nearby organisms.

What is the impact of forest health on aesthetics?

Diseased or infested trees can create unattractive landscapes, while sustainable practices can enhance natural beauty.

How can fire risk be managed in forests?

By removing unnecessary and dying plants, understory vegetation, and combustible surface fuels.

What role do healthy forests play in climate change?

act as carbon sinks, absorbing carbon dioxide and reducing overall climate impacts.

What is sustainable forestry?

Management that focuses on mitigating and adapting to climate change to promote forest ecosystems for future generations.

What does the Oregon Forest Practices Act (FPA) regulate?

sets standards for all commercial activities involving trees on non-federal forestlands in Oregon.

Who administers and enforces the Oregon Forest Practices Act?

The Oregon Department of Forestry (ODF).

What is the primary focus of private timber companies in Oregon?

Timber production while adhering to FPA regulations.

How do economic factors influence forest management decisions?

Revenue demands can lead to practices like thinning and harvesting to maximize profit.

What social factors impact forest management?

Local community demands and public interests can complicate large-scale management techniques.

What ecological factors are considered in forest management?

Sustainability and biodiversity, including soil health and wildlife habitat efforts.

How is technology used in forest management?

Drones for surveys, cameras for wildlife monitoring, and sensors for early threat detection.

What are the benefits of trees in urban settings?

help fight climate change, improve air quality, provide shade, and enhance community well-being.

What economic products do forests provide?

Timber, fiber for housing and furniture, non-timber products like medicine and food, and biomass for energy.

What are ecosystem services provided by trees?

Food, raw materials, freshwater, and genetic resources essential for human health.

What regulating services do trees provide?

Climate regulation, air quality maintenance, water purification, and erosion control.

What cultural services do forests offer?

Recreation, spiritual and aesthetic benefits, and health improvements.

What supporting services do trees provide?

Soil formation, nutrient cycling, and habitat provision for various species.

What are the three elements of the fire triangle?

Oxygen, fuel, heat

What are the three sides of the sustainability triangle?

economics, environmental, social

Name two major forest certification systems used in Oregon

American Tree Farm System and Forest Stewardship Council

Define “SSBT”

Salmon, Steelhead, and Bulltrout

Define ladder fuels

Live or dead vegetation that allow fire to climb from the forest floor to the canopy

Two insect pests affecting Oregon forests

Spruce budworms and emerald ash borers

Why are trees considered a renewable resource

They can be replanted and harvested