Forested Landscapes in Perspective Prospects and Opportunities for Sustainable Management of America's Nonfederal Forests (1998) / Chapter Skim
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Part Three: Major Policy and Program Level Issues Across the Landscape--5 Changing Conditions of the Forest
Part Three: Major Policy and Program Level Issues Across the Landscape--5 Changing Conditions of the Forest
Pages 55-71
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From page 57... ...
. These conditions include loss of biological diversity, diminished water quality, effects of global climate change, and increased timber mortality.
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From page 58... ...
Only about 15 percent of the original forests remain, mostly in Alaska; the structure and composition of other forests appear to differ from pre-European settlement forests. Even where forest cover has returned, for example in the Northeast, residential development has intruded on recovering forest areas and reproductive success of neotropical migratory bird species remains low (Friesen et al.
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From page 59... ...
1994~. The potential of nonfederal forestlands to contribute to the maintenance of biodiversity is great, given their extent, variety, potential management flexibility, and that they are the primary forest category subject to conversion to nonforest uses.
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From page 60... ...
Numerous studies of breeding birds in small urban woodlots and woodlots of the eastern United States have shown severe population declines, particularly of neotropical migrants, between the late 1940s and the late 1980s. Although the specific ecological mechanisms responsible are poorly understood, the studies attributed the decreases, in part, to forest fragmentation (Finch 1991~.
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From page 61... ...
Most of the habitat losses have occurred in the South, Northeast, Midwest, and California; these areas also have the highest proportions of nonfederal forests in the United States. The 10 most endangered forest types are southern Appalachian spruce-fir forest, longleaf pine forest and savanna, southeastern riparian forests, Hawaiian dry forest, California riparian forests and wetlands, old-growth eastern deciduous forests, old-growth Pacific Northwest forests, old-growth white pine forests, oldgrowth ponderosa pine forests, and southern forested wetlands.
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From page 62... ...
An additional constraint to shifting the timber harvest from federal to private lands is that many industrial private forestlands in the southern United States already are heavily devoted to producing pulp fiber for paper production, and nonindustrial forestlands of the region are decreasing in area (Table Am.
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From page 63... ...
Under any definition of "sustained yield management," increases in yield resulting from more intensive management should offset the additional inputs, and wood harvested over multiple harvest intervals should at least remain constant. One recent change in management practice that is viewed as positive according to most criteria is the enhanced training of loggers and the adoption of "reduced-impact harvesting," whereby residual trees and other aspects of long-term ecosystem functioning are minimally affected by logging operations (Mackay et al.
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From page 64... ...
It can be used as an effective management tool to maintain fuel loads at manageable levels, particularly in ecosystems where fire was historically frequent and low in intensity. Trade-offs between prescribed fire smoke and wildfire smoke might be necessary to defend prescribed burning because of the air-quality effects.
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From page 65... ...
property and natural and cultural resources based on relative values to be protected, commensurate with suppression costs. That redefinition implies a cutting back of urban-interface structural protection by federal fire fighting forces and a shifting of cost to state and local agencies.
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From page 66... ...
Air quality definitely is affecting tree and forest health in many urban forests and in forests in airsheds surrounding large urban areas. These areas deserve special attention, because they vividly show the acute long-term effects of air pollution on trees and forests (for example, ozone damage to ponderosa pine trees in the San Bernadino Mountains outside Los Angeles; Miller and Evans 1974~.
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From page 67... ...
(1988) determined that hydrocarbon emissions from pine forests in the southeastern United States could account for the fact that, although hydrocarbon and sulfur emissions from automobiles had been greatly reduced, NOx was still emitted in sufficient amounts to combine with biogenic hydrocarbons from pine forests so that ambient air concentrations of ozone in Atlanta had essentially not changed.
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From page 68... ...
Nonindustrial private forestlands offer the greatest opportunity for increasing terrestrial carbon storage in the United States, because of their availability (compared with land currently in cultivation) and underuse as illustrated by their low stocking density and volume estimates (Powell et al.
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From page 69... ...
Some, such as chestnut blight, have resulted in near extirpation of native species by killing the host. Other organisms will affect future losses: white pine blister rust damages mature and kills young whitebark pine, the seeds of which are a critical source of food for grizzly bears in the Rocky Mountains.
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From page 70... ...
Watershed integrity has been of concern to programs administered through the USDA and have often focused on watershed restoration (Agricultural Conservation Programs [ACP] and Conservation Reserve Program [CRP]
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From page 71... ...
SUMMARY OF FINDINGS AND RECOMMENDATIONS Fundamental sustainability of the ecosystems that are a part of nonfederal forestlands is critical to the production of goods and services that Americans are likely to expect from these forests in the future. The problems caused by forest fragmentation, land conversion, intensive land management, fire, pollution, climatic change, insects, disease, and alien plants are landscape-level and cross the boundaries of many ownerships.
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