Treesearch

We computed the dynamic response of an idealized thermometric net radiometer, when driven by an oscillating net longwave radiation intended roughly to simulate rapid fluctuations of the radiative environment such as might be expected during field use of such devices. The study was motivated by curiosity as to whether non-linearity of the surface boundary conditions implies the existence of a nonvanishing mean signal even when mean forcing (i.e. mean net radiation) vanishes. These simulations do not prove (and owing to discretization and roundoff error, cannot prove) such a bias is absolutel...

The key to stopping high-frequency or catastrophic wildfires in the western U.S. is the successful restoration of burned lands to native plant communities. Developing models of establishment for invasive and native species will help in the selection of species for restoration projects that are able to establish and compete with invasive species given the abiotic conditions of specific sites. Modeling germination is the first step in modeling seedling establishment. We incubated 10 revegetation species and 3 Bromus tectorum collections at constant temperatures to develop linear and curviline...

The lack of knowledge regarding social diversity in the Wildland Urban Interface (WUI) or an in-depth understanding of the ways people living there interact to address common problems is concerning, perhaps even dangerous, given that community action is necessary for successful wildland fire preparedness and natural resource management activities. In this article, we lay out the knowledge and preliminary case study evidence needed to begin systematically documenting the differing levels and types of adaptive capacity WUI communities have for addressing collective problems such as wildland...

Agropyron cristatum [L.] Gaertner (crested wheatgrass) continues to be seeded on burned wildlands. Effective control methods need to be developed to convert these seedings to more diverse native plant communities. This research was designed to determine effective ways to control A. cristatum and establish native species while minimizing weed invasion. We mechanically and chemically treated two sites followed by seeding native species. The study was replicated for 2 years as a randomized block split plot design with five blocks. Within each block, 0.4 ha main plots were either left undisturb...

Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis) is a dominant shrub throughout much of the interior western United States. It is a key component of sagebrush steppe ecosystems, which have been degraded due to European settlement, improper land use, and changing fire regimes resulting from the invasion of exotic annual grasses. Re-establishment of this shrub has relied largely on direct seeding, but success has been erratic; outplanting nursery grown seedlings may be a more effective method of establishment. This study was initiated to identify the effect of three...

This report traces the flow of Wyoming's 2005 timber harvest through the primary timber-processing industry to the wholesale market and residue-using sectors. The structure, capacity, operations, and conditions of Wyoming's primary forest products industry are described; and volumes and uses of wood fiber are quantified. Historical and recent changes in Wyoming's forest products industry, including harvest, production, and sales are also discussed.

Since 1990, native bark beetles have killed billions of trees across millions of acres of forest from Alaska to northern Mexico. Although bark beetle infestations are a regular force of natural change in forested ecosystems, several of the current outbreaks, which are occurring simultaneously across western North America, are the largest and most severe in recorded history.

Currently, Forest Inventory and Analysis estimation procedures use Smalian's formula to compute coarse woody debris (CWD) volume and assume that logs lie horizontally on the ground. In this paper, the impact of those assumptions on volume and biomass estimates is assessed using 7 years of Oregon's Phase 2 data. Estimates of log volume computed using Smalian's formula are known to be biased, overestimating volume. On the other hand, volumes estimated from the diameter at the point of intersection between the log and the transect are approximately unbiased, regardless of log shape, but may...

A growing recognition of the importance of downed woody materials in forest ecosystem processes and global carbon budgets has sharpened the need for efficient sampling strategies that target this resource. Often the aggregate volume, biomass, or carbon content of the downed wood is of primary interest, making recently developed probability proportional-to-volume designs such as line intersect distance sampling (LIDS) of interest. This research presents field results from LIDS and conventional line intersect sampling (LIS) inventories of coarse woody debris (CWD) in three stands in northwest...

Previous studies have shown a high correspondence between tree height measurements acquired from airborne LiDAR and that those measured using conventional field techniques. Though these results are very promising, most of the studies were conducted over small experimental areas and tree height was measured carefully or using expensive instruments in the field, which is not feasible in a practical forest inventory context. In this study, 105 plots located west of the Kenai Mountains, Kenai Peninsula, Alaska were measured and LiDAR data over the same set of field plots were acquired. Plot...