1. Old-Growth Forests and Deforestation

2. Old-Growth Forests Characteristics Ex: Pacific Northwest
Trees at least 250 years old
Multi-level canopy
Standing dead trees and fallen logs
Ex: Pacific Northwest
Noted for Douglas Fir trees that are hundreds of year old, but still have trees of all species and sizes

3. Old-Growth Forests
Variety of tree species and sizes help to make a healthy ecosystem
Healthy mature trees
Produce seeds to grow new trees and provide food
Dead and dying trees play an important role

4. Old-Growth Forests Snags
Standing dead or dying trees
When snags topple over, it opens up a canopy letting sunlight through
Fallen trees provide habitats for smaller organisms
Nurse logs
Young seedlings take root and grow
Provide evidence of natural recycling process

5. Logging Forests
Forests regulate climate by recycling water and carbon dioxide.
On hot days a large tree may absorb 5.5 tons of water from the soil and release it into the atmosphere through its leaves in a process called transpiration.

6. FORESTRY PRACTICES Forests are logged by two different methods:
CLEAR CUTTING – every tree is cut down whether it has value or not and the unnecessary trees are left
SELECTIVE CUTTING – only certain trees are cut down depending on what they are needed for ( firewood, paper, furniture or lumber)

7. EVALUATING A CLEAR-CUT
Company’s point of View
1. Less expensive – provide timber or pulp at a more competitive price
2. Company can choose which trees to plant – get better price for when the area is logged again in the future.

8. EVALUATING A CLEAR-CUT
Ecological Point of View
1. Soil erosion and runoff into local streams increases – increasing growth of algae
2. Eroded soil forms sediment in streams, affecting spawning areas of fish.
3.Removal of vegetation on the ground exposes the soil, increasing the warming of the area in summer and cooling in winter
Exposure also increases water loss from the soil.

9. EVALUATING A CLEAR-CUT
Clear-cut creates completely different abiotic and biotic conditions in the area.
Ecosystem must change – therefore the community must change.
Loss in forest plants – loss of forest animals

10. DEFORESTATION Is any removal of trees from the area of land.
Deforestation affects the environment in many ways:
1. Erosion – tree roots hold soil in place during heavy rains
2. Nutrient Loss – nutrients are washed away with the rain instead of being absorbed by the trees

11. DEFORESTATION
3. Temperature Change – the ground will absorb more energy and affect organism functions
4. Carbon Cycle Change - no trees to take in CO2 and to make O2
5. Food Web Changes – less producers at the beginning of food chains
6. Habitat loss – nesting areas and ground cover disappears

12. A logger would say that this tree was overmature
A logger would say that this tree was overmature. What would an ecologist say?

13. Multiple Use Management
Most old-growth timber on private land is already gone
Nearly all old-growth wood is in National forests and managed by government
U.S. Forests service can sell permits to log these areas

14. Multiple Use Management
There are roughly 191 million acres in our national forests
Law requires national forests to be managed for multiple uses
Timber
Mining
Watershed protection
Grazing
Recreation
Fish and wildlife habitats

15. Multiple Use Management
Local economy can be tied to “uses” permitted on federally owned land
Conflicts often occur with these multiple uses
Water quality can be damaged by improper disposal during oil and gas production
Critics of the Forest Service say timber harvest is given priority over other uses

16. Conflict in the Northwest
Logging is most controversial environmental issue in this area
Ecologists believe wood should stay in the forest
No such thing as waste in the forest
Death and decay of Douglas Fir tree provide life for other organisms
Foresters, hired by commercial timber companies consider these forests to be “overmature”
To foresters, timber is a crop and is ready for harvesting
Believe it is wasteful to allow valuable timber to decompose on forest floor

17. How much is enough? National Forest Management Act (1976)
Requires management plans to be made for every national forest
Timber companies were logging old-growth timber at a rate of 60,000 acres per year, in 1987
Court ruled service plans for Pacific Northwest were inadequate and logging was stopped

18. How much is enough? Northwest Forest Plan was adopted in 1994
Based on ecosystem management approach
Requires government agencies to survey and manage these forests
Permits logging only in areas that do not disrupt habitat of ecologically important organisms