Forests

'Functions' of Forests

• wildlife habitat
• firewood, lumber, & paper products
• recreation
• important in global recycling of water, oxygen, carbon, & nitrogen
• forest ecosystems represent the most important CO₂ reservoir world-wide
• absorb, hold, & slowly release water, which reduces erosion & flooding

Status of the World's Forests

Major causes of loss in forest cover:

• expansion of agriculture
• logging
• cattle ranching
• expansionist government policies

Status of U.S. Forests

• Forests cover about one-third of the United States, about 70% of their extent at the time of European settlement.
• About 40% of U.S. forest lands are publicly owned. Of these, roughly 15 percent are in protected areas (primarily national parks and wilderness areas) where timber harvest is not allowed.
• Private forests (60% of U.S. forests) are owned by forest products companies, other firms, and individual landowners.

Source: USDA Forest Service

U.S. National Forests:

• 156 National Forests (including the Daniel Boone National Forest in Kentucky) managed by U.S. Forest Service

http://www.fs.fed.us/recreation/map.shtml

• currently managed under MULTIPLE USE SUSTAINED YIELD ACT of 1960 & the 1974 & 1976 FOREST RESERVES MANAGMENT ACTS
• Sustained yield - should be a balance between new planting & growth and the amount of wood removed by cutting, pests, disease, & fire
• Multiple use - forests should be used for a variety of purposes, including recreation, timber production, mining, grazing, and so on
• By law, the Forest Service must maximize the net social and economic benefits of its management programs for all Americans and fully account for the benefits of unlogged forests and the costs of logging in its timber sale program decisions. Unfortunately, the Forest Service ignores this type of analysis when justifying the timber sale program to Congress and the American people. At every level of planning, the Forest Service has typically ignored the vast ecosystem service values of unlogged forests and externalities of the logging program. Instead, the only economic benefits and costs quantified at any level of timber sale program planning are those benefits and costs attributable to the sale and processing of wood products. The result is a public lands logging program that operates at a net loss of nearly $1 billion each year. The American people pay for timber sale administration, logging road construction and repair as well as damage from floods, mudslides and forest fires caused by logging. Timber companies' contributions to these costs are minimal. From 1980 to 1991, the U.S. Forest Service timber program operated at a net loss of $7.3 billion. In fiscal year 1996, nearly $800 million was appropriated from the general fund of the U.S. Treasury and another $532 million was spent from off budget accounts for the timber sale program. None of these receipts were returned to the Treasury, resulting in a net loss to taxpayers of at least $800 million. (Hanson, Chad, "Ending Timber Sales on National Forests, The Facts," 1997.)

Forest Management

• Forests are harvested by selective cutting, shelterwood cutting, seed-tree cutting, or clear-cutting
• selective cutting
• careful removal of more mature trees
• provides more light for growth of remaining trees
• allows natural regeneration
• requires more care and produces lower profits
• preferred harvesting technique for wildlife, habitat stability & esthetics.
• “High-grading”, especially common in the tropics, is a environmentally-less-desirable variation because all the trees of a few valuable species are cut and because much of the remaining forest is damaged & diversity

is reduced.
• clear-cutting = even-aged management
• all trees are cut in patches, strips, or the entire stand
• produces high yields & profits
• sites are often burned then replanted in 1 species

• shelterwood cutting
• all mature trees are removed through a series of cutting over a 10-yr. period.  This opens the

canopy & lets in light to promote growth of remaining trees, which tend to be even-aged.
• seed-tree cutting
• most trees are removed, except for several mature, high quality trees of each species that provide seeds for future regeneration.
• Remaining seed trees are exposed to blow-down; habitat is very open following cutting.

Status of forests in the eastern U.S.:

• EASTERN FORESTS FACING MULTIPLE THREATS
• Forests in the southeastern U.S.
• Chip mills
• Appalachian mixed mesophytic forests
• Central U.S. hardwood forests
• Status of Kentucky's forests

Loss of tropical forests

• cover 6% of Earth's land area (roughly area of the contiguous U.S.)
• grow in equatorial Latin America, Africa, & Asia
• about 1/2 already lost (primarily since 1950)
• currently being lost at rate of 59,000 square miles per year (or 2 football fields/second)

Why should we care about tropical forests?

• home to 50-90% of Earth's species; most still unknown
• supply hundreds of food products (e.g., coffee, tea, cocoa, spices, nuts, chocolate, & tropical fruits)
• provide materials like rubber & dyes
• provide active ingredients for 25% of world's prescription drugs; 70% of the 3,000 plants identified by the National Cancer Institute as sources of cancer-fighting chemicals come from tropical forests
• most of the original strains of rice, wheat, & corn that supply more than half of the world's food were developed from tropical plants

• Population growth & poverty
• Unsustainable farming
• Cattle ranching
• between 1965 & 1983, Central America lost 2/3 of its tropical forests to cattle ranches ==> much beef exported to U.S., Canada, & Europe
• Mining
• gold mining is particularly damaging (pollutes streams & soils with mercury)
• Dams

Itaipu Dam

• Commercial logging
• about 75% of exported tropical timber comes from southeast Asia & this timber is largely imported by Japan (53%), Europe (32%), & the U.S. (15%)
• several large corporations (like Boise Cascade) are major destroyers of rainforests

• slow population growth & discourage poor from migrating to undisturbed tropical forest (by reducing poverty)
• help new settlers learn small-scale sustainable agriculture
• pressure international lending agencies (e.g. World Bank & Citigroup) not to lend money for environmentally-destructive projects (e.g., road building & dams)
• debt-for-nature swaps & conservation easements
• tighter timber-cutting regulations & reduced demand for timber

Useful links:

National Forest Protection Alliance

Tropical Deforestation

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