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The Recreation Fee Demonstration Program (RFDP) is a pilot program authorized by Congress in 1996. The RFDP allows the U.S. Department of Agriculture Forest Service, and the United States Department of the Interior Park Service, Bureau of Land Management, and Fish and Wildlife Service to experiment with new or increased fees at up to 100 recreation sites per agency. The RFDP has sparked a public debate about the merits and demerits of charging fees for recreation on public lands. This study analyzed the debate about the RFDP on national forests that is expressed in a large electronic...

The Missouri Ozark Forest Ecosystem Project (MOFEP) is an experiment designed to determine the effects of forest management practices on important ecosystem attributes. MOFEP treatments evaluated include even-aged, uneven-aged, and no management treatments. Forest vegetation provides a common ecological link among many organisms and ecological processes, and therefore monitoring forest vegetation before and after management treatments is a high priority on MOFEP. Between 1990 and 1994, 645 permanent vegetation plots were established on the nine MOFEP sites to inventory woody vegetation,...

Therefore, in this chapter we focus on ecosystem diversity, defined as the number, kind, and pattern of landscape and waterscape ecosystems in a specified area and the ecological processes that are associated with these patterns (Lapin and Barnes 1995). One can then characterize eeosysterns as to their composition, structure, and function -- the attributes Of diversity (Crow et al. 1994). Our objectives are to: (1) provide an example of a landscape ecosystem approach to characterizing ecosystem diversity in riparian areas by presenting a case study, (2) consider the importance of riparian...

The 1998 Indiana/Illinois forest inventory (USDA Forest Service, Forest Inventory and Analysis (FIA)) used Landsat Thematic Mapper (TM} data for stratification. Classified images made by the National Gap Analysis Program (GAP) stratified FIA plots into four classes (nonforest, nonforest/forest, forest/nonforest, and forest) based on a two pixel forest edge buffer zone. Estimates based on twophase sampling for stratification were made at the county level. This procedure differed from methods used in previous inventories where stratification was based on the stereoscopic examination of...

A plot selection approach is proposed based on experience from the Annual Forest Inventory System (AFIS) in the Aspen-Birch Unit of northestern Minnesota. The emphasisis on a mixture of strategies. Although the Agricultural Act of 1998 requires that a fixed 20 percent of plots be measured each year in each state, sooner or later we will need to vary the scheme to accommodate pressing user needs and budget constraints while still preserving the integrity of the annualized cycle. Differing probabilities of selection will need to be accommodated; variance and confidence interval estimation...

A critical component of any silvicultural treatment is the creation of suitable microclimatic conditions for desired plant and animal species. One of the most useful tools for examining the microclimatic implications of different vegetation treatments is the use of atmospheric boundary-layer models that can simulate resulting micrometeorological conditions within and above vegetation layers. A two-dimensional atmospheric boundary-layer model has been successful in sitmulating the atmospheric environments within and above, forest vegetation layers that have undergone different types of...

Three factors, human population density, topography, and culture interact to create temporal and spatial differences in the frequency of fire at the landscape level. These factors can be quantitatively related to fire frequency. The fire model can be used to reconstruct historic and to predict future frequency of fire in ecosystems, as well as to identify long-term changes in anthropogenic fire regimes. Topographic roughness is positively related by a regression equation to the length of mean fire intervals indicating that fires are less frequent in rough than in flat terrain during...

Established populations of the pine shoot beetle, Tomicus piniperda (L.) (Coleoptera: Scolytidae), were first detected in the US in 1992. As of January 2000, T. piniperda was known to be established in 271 counties in 11 US states (IL, IN, MD, MI, NH, NY, OH, PA, VT, WI, WV) and 25 counties in Ontario and 8 counties in Quebec, Canada. In a 1998 study, we found that marked and released T. piniperda were captured in traps up to 400m outside of operational sawmills and simulated millyards despite the abundance of brood material present in the millyards; 400m was the furthest distance to which...

Estimates of the total number of exotic (non-indigenous) organisms that are now established in the United States(US), range from 4,500 (US Congress1993) to more than 50,000 (Pimentel et al. 2000), of which more than 400 are insects that feed on trees and shrubs and another 20 are disease organisms of trees(Haack and Byler 1993, Mattson et al. 1994, Niemela and Mattson 1996). Several of these exotic tree-feeding insects-- gypsy moth (Lymantria dispar), smaller European elm bark beetle (Scolytus multistriatus), hemlock woolly adelgid(Adelges tsugae), and beech scale(Cryptococcus fagisuga)--...

When a gap forms in a forest canopy, the first and most immediate effect on the exposed area is an increase in radiative exchange near the ground. More sunlight reaches the ground during the daytime, and at nighttime the ground is more exposed to longwave radiation influences from the sky. These changes in radiation lead directly to a different near-ground temperature climate than what existed previously. Furthermore, spatial gradients in radiation and temperature now exist within the gap region that did not exist before the gap formed.