Treesearch

Fire-dependent lodgepole pine stands comprise significant acreages of midand upper-elevation forests in the Northern Rockies, providing wood products, wildlife habitat, livestock forage, water, recreational opportunities, and expansive viewsheds. Many lodgepole pine stands are in late-successional stages and at risk to pests and catastrophic-scale fires. Tenderfoot Creek Experimental Forest is located on the Lewis and Clark National Forest in the Little Belt Mountains of Central Montana. Twenty percent of the lodgepole pine stands on the experimental forest were found to be two-aged and...

A new biophysical model (FORFLUX) is presented to study the simultaneous exchange of ozone, carbon dioxide, and water vapor between terrestrial ecosystems and the atmosphere. The model mechanistically couples all major processes controlling ecosystem flows trace gases and water implementing recent concepts in plant eco-physiology, micrometeorology, and soil hydrology. FORFLUX consists of four interconnected modules - a leaf photosynthesis model, a canopy flux model, a soil heat-, water- and CO2- transport model, and a snow pack model. Photosynthesis, water-vapor flux and ozone uptake at...

Assume for the moment that you are the supervisor of the Roosevelt National Forest (it’s located near our town of Fort Collins, Colorado). You have been asked by the Chief of the Forest Service how you would spend a specified increase in your budget. You could spend the increase on such projects as improved campgrounds, better roads for reaching the backcountry, reduction in forest fuels to lower the risk of wildfire, and watershed management to lower erosion and thereby improve fish habitat. You know your chances of getting an increase depend on how well you support your proposal. You can...

The effect of a population's location on the landscape on genetic variation has been of interest to population genetics for more than half a century. However, most studies do not consider broadscale biogeography when interpreting genetic data. In this study, we propose an operational definition of a peripheral population, and then explore whether peripheral populations of Canada lynx (Lynx canadensis) have less genetic variation than core populations at nine microsatellite loci. We show that peripheral populations of lynx have fewer mean numbers of alleles per population and lower expected...

After wildfires in 1996 in the sagebrush(Artemisias pp.) and pinyon-juniper (Pinus spp.-Juniperus spp.) zones of west-central Utah, the USDI-BLM attempted to reduce soil erosion and cheatgrass proliferation (Bromus tectorum L.) through rehabilitation treatments. We compared the vegetation of aerially seeded, chained treatments with aerially seeded but non-chained treatments for 3 years following seeding. Vegetation cover increased significantly in both treatments between the first and second year, concurrent with above-average precipitation. By the second year, seeded grasses, primarily...

Conservation of native fishes and changing patterns in wildfire and fuels are defining challenges for managers of forested landscapes in the western United States. Many species and populations of native fishes have declined in recorded history and some now occur as isolated remnants of what once were larger more complex systems. Land management activities have been viewed as one cause of this problem. Fires also can have substantial effects on streams and riparian systems and may threaten the persistence of some populations of fish, particularly those that are small and isolated. Despite...

Tree age and fire history were studied in an unlogged ponderosa pine/Douglas-fir (Pinus ponderosa/Pseudotsuga menziesii) landscape in the Colorado Front Range mountains. These data were analysed to understand tree survival during fire and post-fire recruitment patterns after fire, as a basis for understanding the characteristics of, and restoration needs for, an ecologically sustainable landscape. Comparisons of two independent tree age data sets indicated that sampling what subjectively appear to be the five oldest trees in a forest polygon could identify the oldest tree. Comparisons of...

Prior to the 20th century, low intensity fires burned regularly in most arid to semiarid forest ecosystems, with ignitions caused by lightning and humans (e.g., Baisan and Swetnam 1997, Allen et al. 2002, Hessl et al. 2004). Low intensity fires controlled regeneration of fire sensitive (e.g., grand fir [Abies grandis]) species (Arno and Allison-Bunnell 2002), promoted fire tolerant species (e.g., ponderosa pine [Pinus ponderosa], Douglas-fir) [Pseudotsuga menziesii], maintained an open forest structure (Swetnam et al. 1999), reduced forest fuel loads, decreased the impacts of insects, and...

Burn severity (also referred to as fire severity) is not a single definition, but rather a concept and its classification is a function of the measured units unique to the system of interest. The systems include: flora and fauna, soil microbiology and hydrologic processes, atmospheric inputs, fire management, and society. Depending on the particular system of interest, the unit of measure changes. For example, in fire management the units of measure include consumption of organic material, flame length, torching index and other indicators of risk and fire behavior. For the atmosphere the...

Wildfires of 2000 and 2001 burned thousands of hectares in the Northern Rocky Mountains. Within the fire parameters, 162 Forest Inventory and Analysis (FIA) plots burned in Idaho and Montana where pre-wildfire information on forest structure, vegetation composition, soil productivity, and surface fuels was documented; thus providing a unique opportunity to assess wildfire effects on forest resources at multiple spatial scales. This is a collaborative effort among FIA-Interior West, Rocky Mountain Research Station, and FHM. To date, crews have characterized burn severity on forest floor,...