Treesearch

Severe wildfires often have dramatic short-term effects on water quality, although there is increasing evidence that in some catchments their effects can persist for many years. Forest recovery after the 2002 Hayman Fire burned catchments that supply drinking water to over a half million users in Denver, CO, has been extremely slow and has caused persistent water quality concerns. To evaluate whether postfire water quality changes increase the potential to form undesirable by-products of water disinfection, we compared stream water from eight burned catchments within the Hayman Fire and...

Integrated landscape management of key population areas along with the corridors linking them is important for tiger conservation in the Indian subcontinent. Relationships between gene flow and landscape patterns, however, cannot be generalized given that different limiting factors influence movement in different spatial contexts. Here, we study the landscape features affecting tiger gene flow in the Western Ghats, and examine how and why limiting landscape features differ between Central India and the Western Ghats. We also assess whether these landscape features have been altered by land...

A thinning study was established in 1967 in moist mixed forests on the Priest River Experimental Forest in northern Idaho, USA. The study design included three thinning intensities: low, moderate, and high intensity (1,976, 988, and 494 trees ha-1). This study examined short-term (11 years) and long-term (50 years) thinning effects on residual stand characteristics, growth, and yield. Since regeneration may occur after thinning, understory change was also addressed. Thinning decreased stand density immediately but improved the growth of residual trees. Shade-tolerant species were favored...

Bark beetles are responsible for large numbers of dead trees in ponderosa pine forests in the United States. The relationship between tree mortality caused by bark beetles and increasingly severe wildfires has been analysed by Carolyn Sieg and colleagues using a detailed physics-based fire behaviour model. The team seeks to understand if fires that follow beetles are more severe, that is if they leave less green foliage, or if the tiny beetles could have more complex interactions with subsequent wildfires than previously understood.

Landscape level species assessments are rarely available to inform conservation planning. Recent advances in multi-taxa survey techniques, however, have made them more obtainable by improving efficiency of collecting species occurrence data and genetic samples. Here, we used a multi-taxa survey technique to provide a landscape level portrait of fisher (Pekania pennanti) population status in a portion of the northern Rockies where the species’ history has been heavily influenced by humans. From 2010 to 2014 we deployed 497 winter forest carnivore bait stations across a 23,000 km2 study area...

Wildfires in southwestern US ponderosa pine (Pinus ponderosa Lawson & C. Lawson) forests have recently increased in size and severity, leaving large, contiguous patches of tree mortality, and raising concerns about post-fire recovery. Ponderosa pines are a dominant species in the Southwest and they evolved with low- to moderate-severity fire regimes. They are poorly adapted to regenerate after large, high-severity fires because they do not have serotinous cones, re-sprouting capabilities, or long-lived seed banks. Additionally, high-severity fires can favor competing understory plants or...

Herbicide treatments in viticulture can generate highly contrasting mosaics of vegetated and bare vineyards, of which vegetated fields often provide better conditions for biodiversity. In southern Switzerland, where herbicides are applied at large scales, vegetated vineyards are limited in extent and isolated from one another, potentially limiting the distribution and dispersal ability of organisms.

The Sunda clouded leopard is vulnerable to forest loss and fragmentation. Conservation of this species requires spatially explicit evaluations of the effects of landscape patterns on genetic diversity, population size and landscape connectivity.

Sagebrush ecosystems are a major component of western U.S. landscapes and they provide vital habitat to a wide array of wildlife species, including greater sage-grouse and pygmy rabbits. However, in recent decades, sagebrush ecosystems have been reduced or degraded by a wide range of disturbances, including human development, overgrazing, severe fires, and encroachment by cheatgrass and pinyon-juniper woodlands. These factors are expected to continue or worsen with anticipated climate change.

With concern over the health of aspen in the Intermountain West, public and private land managers need better guidance for evaluating aspen condition and selecting and implementing actions that will be effective in restoring aspen health. The Utah Forest Restoration Group collaboratively synthesized a step-by-step approach for aspen restoration that was applicable to western U.S. forests. In a successful case study in shared stewardship, these restoration guidelines were applied to a challenging real-world setting.