Treesearch

Over the past decade, native bark beetles (Coleoptera: Curculionidae) have killed billions of trees across millions of hectares of forest from Alaska to Mexico. Although bark beetle infestations are a regular force of natural change in forested ecosystems, several current outbreaks occurring simultaneously across western North America are the largest and most severe in recorded history. Bark beetle ecology is complex and dynamic, and a variety of circumstances must coincide for a large scale bark beetle outbreak. While outbreak dynamics vary from bark beetle species to bark beetle species...

The purpose of this study is to examine the effects of visible visitor-caused impacts as characterized by user-created campsites on judgments about the perceived restorative character in natural areas. User-created campsites were inventoried using mapping-grade mobile Geographic Information Systems (GIS) technology and photography. Photography of user-created campsites was accomplished by collecting high-resolution spherical panoramic imagery at select user-created campsites. Collected data were postprocessed and added to a GIS. This technique not only overcomes the challenge of locating...

Biological control of noxious weeds is an effective and widespread method often used by rangeland managers in the western United States. However, once biological control agents, usually insects, are released onto public and private lands there are few, if any, programs to follow up and monitor the effectiveness of these agents. A technique being used by some land managers is the use of student crews to implement monitoring programs. The Southern Idaho Bio-Control (SIBC) program is one program that has successfully used student crews during the past 10 years for this purpose.

Wildland fire is one of the most important vegetation- shaping factors that land managers deal with. It is our highest risk, most complex, and potentially highest consequence program. Wildland fire management policy is the most important element in defining the direction, scope, and focus of the program. What is policy? If we look it up in Merriam-Webster's dictionary, it is a "high-level overall plan embracing the general goals and acceptable procedures, especially of a governmental body." It is interesting to see that the dictionary defines policy as a province of a government. Fire...

Since its origin as a defined functional activity, wildland fire management has been the natural resource management program with the highest risk, complexity, and greatest potential for serious negative outcomes. During this time, this program has continually grown in temporal and spatial extent, operational complexity, ecological significance, social, economic, and political magnitude, and seriousness of potential consequences. With this level of importance and dynamic stature, the value of a strong, accurately focused policy to guide programmatic development and implementation cannot be...

PLEASE NOTE: PDF IS ONLY A SAMPLE OF BOOK. A practical volume for the home or business owner on landscaping with native, drought-tolerant plants in the Rocky Mountain West. Filled with color illustrations, photos, and design sketches, over 100 native species are described, while practical tips on landscape design, water-wise irrigation, and keeping down the weeds are provided.

Cheatgrass (Bromus tectorum) is an invasive weed in western North America found primarily growing at elevations less than 2200 m. We asked whether cheatgrass is capable of becoming adapted to a marginal habitat, by investigating a population at a high elevation invasion edge. We used a combination of methods, including reciprocal field transplants, controlled environment studies and molecular analysis. High levels of SSR gene diversity (0.50 vs. 0.43) and comparable variation in phenotypic traits were observed at both the invasion edge and a low elevation, high-density population. Three...

A principal goal of seed germination modelling for wild species is to predict germination timing under fluctuating field conditions. We coupled our previously developed hydrothermal time, thermal and hydrothermal afterripening time, and hydration-dehydration models for dormancy loss and germination with field seed zone temperature and water potential measurements from early summer through autumn to develop predictions of germination timing for Bromus tectorum at a semi-arid site in north-central Utah, USA. Model predictions were tested with a validation dataset based on concomitant seed...

We describe a geoarchaeological survey of a 5-km reach of the Rio Puerco channel and its tributaries, centered on the Guadalupe Ruin, a pueblo of the late 10th-12th centuries A.D. in north-central New Mexico, with associated pollen, charcoal, micromorphological, and radiocarbon analyses. Severe erosion has drastically bisected the Puerco valley with four primary arroyos entering the western side of the Guadalupe reach of the valley: Tapia, Salado, Guadalupe and "No Name." We recorded an 11-m-tall alluvial sequence marked by four phases of cumulic soil development, interrupted by six major...

Climate scientists agree that the earth is undergoing a warming trend, and that human-caused elevations in atmospheric concentrations of carbon dioxide (CO2) and other greenhouse gases (GHGs) are among the causes of global temperature increases. The observed concentrations of these greenhouse gases are projected to increase. Climate change may intensify the risk of ecosystem change for terrestrial and aquatic systems, affecting ecosystem structure, function, and productivity.