Treesearch

We examined the influence of stand density and genotype on transpiration and water use efficiency in high productivity plantations. Three widely planted Eucalyptus clones that differ in drought tolerance and productivity (E. urophylla, E. urophylla x E. grandis and E. grandis x E. camaldulensis, clones IP, B2 and C3, respectively) were measured at four densities (590, 1030, 1420, and 2950 trees ha-1). Over the 1-year study period (1.5-2.5 years after planting), individual biomass increment decreased with increasing density, from 21 kg tree-1 at 590 trees ha-1 to 6 kg tree-1 at 2950 trees...

Increasing the pace and scale of fuel treatments to protect social and ecological values from severe wildfire is a major initiative of numerous land management agencies, organizations, and collaborative groups throughout the western United States, including the Colorado Front Range. Broadcast prescribed fire is a relatively low-cost, effective management tool for achieving fuels reduction at scale but is often challenging to implement due to complex socio-ecological factors. We present results of a multi-criteria suitability analysis intended to identify need, opportunities, and constraints...

The large wildfires of January 2017 burned more than 500,000 ha, including areas of high conservation value native forest, in central Chile. Runoff, streamflow and water balance were measured in a native forest catchment for 7 years before and 2 years after the fires. The annual peak flows and runoff coefficients decreased after the fire as did summer flows and total streamflow. These reductions in flow were despite rainfall being higher in the two years after the fire than in the two years before the fire. The forest re-sprouted vigorously after the fire and evapotranspiration in the...

Theory predicts that species requiring multiple habitat types simultaneously should have heightened sensitivity to anthropogenic pressures, yet tests of this prediction are especially rare. We tested whether breeding site occupancy of the threatened marbled murrelet (Brachyramphus marmoratus) was driven by the synergistic effects of nesting habitat loss in forests, and changing ocean conditions. We paired 70,700 murrelet surveys at 19,837 sites across 20 years from the Oregon Coast Range with annual data on the extent of old forest and biophysical ocean conditions. Dynamic occupancy models...

When the Wildlife Society Bulletin published an article in 1990 based on three years of northern goshawk (Accipiter gentiles) nest monitoring on the North Kaibab Ranger District in Arizona, it ignited a conflict between the timber industry and environmentalists on how to best manage forests.

It is increasingly important to understand how different management actions affect public lands and renewable resources. In response to a lack of standardized monitoring, the Bureau of Land Management (BLM) developed the Assessment, Inventory, and Monitoring (AIM) strategy (Toevs et al. 2011). The AIM approach is based on five key elements: 1) a standardized set of core and contingent indicators, 2) a statistically valid sampling design, 3) a structured implementation process, 4) electronic data capture, and 5) integration with remote sensing. This strategy can help to more efficiently...

Pinon-Juniper (Pinus edulis-Juniperus spp.) woodlands cover approximately 40 million hectares of the western United States (Romme et al. 2009) and provide habitat for a diverse suite of avian species. Several U.S. Fish and Wildlife Service (FWS) Birds of Conservation Concern (BCC) depend on Pinon-Juniper habitats for breeding, including the Gray Vireo (Vireo vicinior). Gray Vireos breed within a limited range only in the hot, arid southwestern USA (Barlow et al. 1999). In New Mexico, they occupy the Pinon-Juniper habitats of foothills, canyons, mesas, and rolling hills. Their populations...

Elk (Cervus elaphus) and mule deer (Odocoileus hemionus) differ in nutritional and structural habitat needs; consequently, management of pinyon-juniper (Pinus spp.-Juniperus spp.) woodlands to provide optimal habitat differs for these herbivores. Diet quality requirements are higher for deer, and are highest for both species during late gestation, lactation, and antler growth. Properly timed treatments, especially prescribed burning, can enhance forage quality and alter forage species composition, providing dietary benefits during these times. Late-winter burns provide a nutrient flush...

Montezuma quail (Cyrtonyx montezumae) are unique among quail with respect to clutch size, diet, covey dynamics, and habitat use. With the exception of a few notable early studies, there is relatively little information on the ecology of Montezuma quail. Previous research has indicated that one of the primary habitats utilized by Montezuma quail is pinyon-juniper woodlands. Throughout many areas of the southwestern United States, pinyon-juniper woodlands are often targeted for thinning projects. Many studies have been conducted on the amount of tree canopy cover needed by other quail...

Pinon-Juniper woodlands, the third largest vegetation type in the United States, encompass 40 million ha of western North America, and occur in 10 western U.S. States (Tausch and Hood 2007, Romme et al. 2009, West 1984, Laylock 1999). Pinon-Juniper thinning and mastication treatments have been used by public lands managers and private landowners throughout the western United States to mitigate fire risk, reduce encroachment, enhance wildlife and livestock forage production, and improve wildlife habitat. The Bureau of Land Management along with private and public partners have treated...