Aspen communities in the western U.S. are considered at risk because of low levels of disturbance and high levels of herbivory by wild and domestic ungulates. There appears to be a trend toward the loss of aspen-dominated stands West-wide. In some cases the loss is caused by succession, with shade-tolerant conifers becoming dominant. On dry sites where aspen is considered to be the climax, dete...

A spen (Populus tremuloides) provides important habitat for mammals and birds 1–3 , improves water retention in watersheds, 4 and has high aesthetic appeal in autumn. However, the amount and quality of aspen cover in the West has been declining for many years. For example, aspen cover in the Dixie and Fishlake National forests in Utah has decreased by more than 60% from historic levels, and in ...

Overview Quaking aspen is generally considered to be a fire-adapted species because it regenerates prolifically after fire, and it can be replaced by more shade-tolerant tree species in the absence of fire. As early-successional aspen stands transition to greater conifer-dominance, they become increasingly fire prone, until fire returns, and aspen again temporarily dominate. While this disturba...

research conducted at Utah State University that identified factors to improve the success of regenerating aspen in southern Utah. Evaluating past si lvicultural regeneration treatments indicated that the presence of pre-harvest advance reproduction, site preparation by broadcast burning, and decreasing browsing pressure could increase the quantity of aspen regeneration. The outcomes are genera...

Question: How does competition between quaking aspen (Populus tremuloides) and white fir (Abies concolor) affect growth and spatial pattern of each species? Location: The northern Sierra Nevada, California, USA. Methods: In paired plots in mixed aspen(n5 3) or white fir-dominated (n5 2) stands, we mapped trees and saplings and recorded DBH, height, species, and condition and took increment core...

Quaking aspen (Populus tremuloides) biomass has declined in Yellowstone National Park (YNP) in the past century. We installed permanent belt transects (plots) for long-term monitoring of aspen stands both within and outside of established wolf pack territories on YNP’s northern range to determine if reintroduced wolves are influencing elk browsing patterns and aspen regeneration through a troph...

Ecologists have debated over the past 65 years whether quaking aspen (Populus tremuloides Michx.) has or has not declined in abundance, vigor, or regeneration in western North America. Many studies have provided divergent interpretations of the condition of aspen forests, leading to difficulty in translating this ecological information into management recommendations. To reconcile these contras...

In western North America, quaking aspen (Populus tremuloides) is the most common hardwood in montane landscapes. Fire suppression, grazing and wildlife management practices, and climate patterns of the past century are all potential threats to aspen coverage in this region. If aspen-dependent species are losing habitat, this raises concerns about their long-term viability. Though lichens have a...

Age-structure analysis of aspen (Populus tremuloides) was conducted on Rocky Mountain elk (Cervus elaphus) winter range in the northern Yellowstone area by collecting increment cores from aspen trees in Yellowstone National Park, the Gallatin National Forest, and the Sunlight/Crandall area of the Shoshone National Forest. Our goal was to compare aspen age structure for elk winter range in the p...

We examined bird-habitat relationships within and across a range of aspen habitats in four major watersheds in the eastern Sierra Nevada mountains of California and Nevada to identify habitat features of importance to aspen-breeding birds. Using point counts and vegetation assessments from 462 individual stations between 2001 and 2003 allowed us to investigate important habitat features at wate...