Treesearch

We tested the prey-base hypothesis to determine whether selection of red squirrel (Tamiasciurus hudsonicus) midden sites (cone caches) by American martens (Martes americana) for resting and denning could be attributed to greater abundance of small-mammal prey. Five years of livetrapping at 180 sampling stations in 2 drainages showed that small mammals, particularly red-backed voles (Clethrionomys gapperi) and shrews (Sorex spp.), were more abundant at midden sites than at non-midden sites. However, logistic regression indicated that middens occurred in spruce– fir (Picea engelmannii -...

In October 2000, the RMRS Leadership Team attended a one-day seminar on leadership presented by Stephen Covey (1990). Covey talked about the role of a leader being respecting, integrating and developing body, heart, mind, and spirit. Integrating our physical, emotional, mental and spiritual selves is a popular theme (e.g. Leonard and Murphy 1995, Levey and Levey 1998, Murphy 1992, Wilber 2000). An example is Segal and Horne's (1997) "Human Dynamics," a personality assessment system similar to Myers-Briggs, but based on physical, emotional, and mental attributes. Covey also talked about...

Long-term monthly evapotranspiration estimates from Brutsaert and Stricker’s Advection-Aridity model were compared with independent estimates of evapotranspiration derived from long-term water balances for 139 undisturbed basins across the conterminous United States. On an average annual basis for the period 1962-1988 the original model, which uses a Penman wind function, underestimated evapotranspiration by 7.9% of precipitation compared with the water balance estimates. Model accuracy increased with basin humidity. An improved formulation of the model is presented in which the wind...

Increasingly more research has focused on characterizing diversity within forest pathogen populations using molecular markers but few studies have characterized features of the landscape that help create or maintain this diversity. Forest diseases commonly occur in patchy distributions across natural landscapes which can be reflected in the genetic composition of the fragmented pathogen populations. This metapopulation structure has seldom been examined by forest pathologists but we believe it offers a potential means to understand the genetic ecology of pathogens in natural landscapes....

Researchers using the eddy covariance approach to measuring trace gas fluxes are often hoping to measure carbon dioxide and energy fluxes for ecosystem intercomparisons. This paper demonstrates a systematic microprocessor- caused lag of 20.1 to 20.2 s in a commercial sonic anemometer-analog-to-digital datapacker system operated at 10 Hz. The result of the inadvertent negative lag (i.e., the digitized analog concentration signal is received before its corresponding instantaneous wind and temperature signal) is a loss in the magnitude of the recorded measured flux. Based on raw field data...

By law, wilderness areas are intended to be unmarred landscapes where evidence of modern civilization is generally absent. This presents a problem, since ecological wilderness conditions have been impaired by human activities. For example, some forest wilderness ecosystems have been altered by livestock grazing, logging, fire exclusion, and through other environmental manipulations. Additionally, there are socio-political factors that must be considered prior to discussing wilderness restoration methods. This paper focuses on the need for ecological wilderness restoration and presents...

Activities were initiated by The Nature Conservancy, the USDA Forest Service, and the Northern Arizona University School of Forestry and Department of Geology in 1996 to restore hydrologic and ecological function to a high-elevation Bebb willow (Salix bebbiana) and mixed grass riparian community in Hart Prairie, near Flagstaff, AZ. Initial restoration removed small water diversions above the willow community to restore hydrologic flow to the downslope community. Because of the small scale of this effort, the viewshed, recreation, and wildlife in the area were not affected. Subsequent...

From 1996 to 1998, the Ponderosa Pine Partnership conducted an experimental forest restoration project on 493 acres of small diameter ponderosa pine in the San Juan National Forest, Montezuma County, Colorado. The ecological basis and the financial analysis for this project are discussed. Specific financial results of the project including products sold, revenues collected, harvesting costs incurred, and profits or losses realized are reported. Restoration costs are also compared with fire suppression costs experienced both in Colorado and nationwide. Using data collected since the...

Ponderosa pine ecosystem restoration in Fort Valley (located east of Flagstaff, Arizona) has been proposed as a method of restoring ecosystem health and lowering the risk of catastrophic wildfire in Flagstaff's wildland-urban interface. Three methods of harvest are being used to carry out restoration treatments: hand harvesting, cut-to-length harvesting, and whole-tree mechanized harvesting. This paper presents a theoretical application of a cost / effectiveness analysis to aid in recommendation of an optimum method of harvest for restoration treatments. Harvest methods can be compared on...

The Grand Canyon Forest Partnership (GCFP), located in Flagstaff, AZ, has implemented a 16-inch diameter breast height cutting cap in the Fort Valley Restoration (Phase One) Project to secure the support of environmental organizations for urban interface forest restoration and fuels reduction projects. This paper provides insights into the economic impacts of this limitation by applying a simulated cap to realistic inventory, logging, and revenue models developed from an earlier representative project - the GCFP's 332-acre Fort Valley Research and Demonstration (R&D) project. The simulation...