Forestry
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Outline
•
World Forests
•
Tropical Forests
 Swidden Agriculture
•
Temperate Forests
 Harvest Methods
 Fire Management
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
WORLD LAND USES
•
Earth’s total land area is about 29% of globe.
 11% of landmass is now used for crop
production.

Half of present forests and grazing lands
could be converted.
-
Immediate and destructive impacts on
landscape and wildlife.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Uses of Landmass (29% of world)
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
WORLD FORESTS
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Forests play vital ecological roles
 Regulating climate, controlling water
runoff, providing food and shelter for
wildlife, and purifying air.
•
Provide valuable materials.
 Wood, paper-pulp.
•
Scenic, cultural, and historic value.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Forest Distribution
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1/3rd of original forests and woodlands have
been converted to other uses.
 Forests and woodlands cover 32% of
earth’s land surface.

Greatest concern is over protection of
Old-Growth Forests.
 Only 22% retain old-growth
characteristics.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
World Forests
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Forest Products
•
Wood plays a part in more activities of the
modern economy than any other commodity.

Industrial Timber and unprocessed logs
account for about half of worldwide wood
consumption.
- Developed countries produce less than
1/2 all industrial wood, but account for
80% of consumption.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Forest Products
•
US, Russia, and Canada are largest
producers of industrial wood and paper pulp.
 Japan is world’s largest wood importer.
- US is both major exporter and importer.
 Buy wood and paper from Canada
and processed wood products from
Japan.
 Sell raw logs to Japan and other
countries.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Forest Management
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Approximately 25% of world’s forests are
actively managed for wood production.
 Sustainable harvest is key to regeneration.
- Most countries replant far fewer trees
than were harvested.
 Many reforestation projects involve
Monoculture Cropping.
 Disrupts ecological processes.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
TROPICAL FORESTS
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Occupy 10% of landmass, and contain:

More than 2/3rds of all higher plant
biomass.

At least 1/2 of all plant, animal, and
microbial species.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Tropical Forests Shrinking
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0.8% of remaining forest cleared each year.
-
Countries have economic and political
reasons to hide extent of losses.

Brazil has largest rainforests, and
highest rate of deforestation.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Tropical Forests Shrinking
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Cattle grazing
Deforestation in
the Amazon Basin
Logging
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Tropical Forest Losses
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Amazon Deforestation Remains High
Even selective logging destroys canopy,
causes river siltation, opens roads
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Desertification threatens forest edges
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Chipko Movement in India
Women blocking
mass logging,
deforestation
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Swidden Agriculture
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Can be ecologically sound and sustainable if
performed carefully and in moderation.
•
Slash and Burn
 Small lot cleared, dried, and burned.
- Ashes used to prepare seedbed.
 Fast-growing crops planted to control
erosion, shade crops, and anchor soil.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Cropped intensively
for 1-2 years,
and then rested
10-15 years.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Logging and Land Invasions
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Other major source of forest destruction

Bulldozed roads make it possible for
people to move into the forest for farmland.
-
Forest clearing leads to river
degradation through increased silt and
sediment flow.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Debt-for-Nature Swaps
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Banks, governments, and lending institutions
hold nearly $1 trillion in loans to developing
countries.

Conservation organizations buy debt
obligations discount, and then offer to
cancel the debt if the debtor country will
agree to protect or restore an area of
biological importance.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
TEMPERATE FORESTS
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Northern countries have a long history of
liquidating forest resources.
 Siberia contains 1/4 of the world’s timber
reserves.
-
Asian companies cutting 10 mil. acres/year
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Temperate Forests in the U.S.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Ancient Forests of the Pacific Northwest
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Redwoods can reach 3-4 m in diameter, 90 m
in height and 1,000 years in age.
 Temperate rainforests are 2nd only to
tropical rainforests in biodiversity.
- Accumulate more biomass in standing
vegetation per unit area.
 Less than 10% of virgin temperate
rainforest remain
 (80% scheduled to be cut).
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Wilderness and Wildlife Protection
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Forest products industry employs about
150,000 people in the Pacific NW
•
Adds nearly $7 billion annually to the
economy.
•
Recreation has 16x jobs.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Spotted Owl controversy

1989 environmentalists sued USFS over
plans to clear-cut remaining old-growth
forests,

Argued spotted owls were endangered and
must be protected.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Spotted Owl controversy
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Spotted Owl controversy
-
Timber industry claims 40,000 jobs lost.
 Environmentalists dispute number.

Other reasons
 Mechanization
 Clear-cutting
 Export of logs to Japan
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Harvest Methods
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Clear-Cutting - Every tree in a given area is
cut regardless of size.
 Fast and efficient, but wastes small trees,
increases erosion, and eliminates wildlife
habitat.
Coppicing - Encourage stump-sprouts.
 Seed-Tree - Leave few mature trees.
 Shelterwood - Remove in series of cuts.

Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Harvest Methods
•
•
Strip Cutting - Harvesting all trees in a
narrow corridor.
Selective Cutting - A small percentage of
mature trees are taken in 10-20 year rotation.
 Can retain many characteristics of mature,
old-growth forests.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Menominee Sustainable Forestry
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Below-Cost Salvage Sales
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USFS has historically regarded its primary
job as providing a steady supply of cheap
logs to the nation’s timber industry.
 Often, timber prices have not been enough
to repay management costs.
- Hidden subsidy to timber industry.
 USFS builds roads in order for timber
companies to extract trees.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
FIRE
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Fires caused by poor logging practices
Wisconsin, 1871:
Deadliest forest
fire in recorded
world history kills
1,200-1,500
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Southeast Asian
Rainforest Fires, 1997
Palm oil plantations
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Mexico/Central America
Rainforest Fires, 1998
Cover for illegal logging
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Brazilian Amazon
Rainforest Fires, 1999
Land-hungry farmers
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Fire Management
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Recent studies show fire plays an important role in
many forested ecosystems.

Eliminating fire has allowed shrubs and small
trees to fill some forest floors.
- As woody debris accumulates, chances of a
major fire increase.

Often, attempts to stop fires cause more
ecological damage than the actual fires.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Fire Suppression:
Wisconsin River Bluffs at Sauk City, 1870s-1990s
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Fire Management
•
For 30 years, the NPS has followed a policy of
allowing some natural fires to burn, and even
setting some prescribed fires.
 But after 70 years of fire suppression, fuel has
now built up to a point where fires can easily
escape “control.”
- The dilemma is how to remove excess fuel
while protecting property, human life, and
forest ecosystems.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Yellowstone Fires, 1988
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.