Changes in the species composition of biotic communities may alter patterns of natural selection occurring within them. Native perennial grass species in the Intermountain West are experiencing a shift in the composition of interspecific competitors from primarily perennial species to an exotic, annual grass. Thus traits that confer an advantage to perennial grasses in the presence of novel ann...

plant litter is an important factor for soil conservation and sustainability that could modify soil chemical properties and increase the plant biomass production. the aim of this research was to compare plant litter chemical composition and its effects on soil properties in three species including hordeum bulbosum, poa bulbosa, bromus tectorum. first, soil samples were taken in the depth of 0-3...

An annotated list of the non-native plant species found in eight eastern Wisconsin natural areas and their relative abundances in 1988 is presented. Except for European buckthorn, aliens were scattered and at low densities, several found mainly along trails. The most seriously invaded sites were Sanders Park and Muskego Park, areas with numerous hiking trails and relatively open, oak-dominated ...

Since the mid-1980s, sagebrush rangelands in the Great Basin of the United States have experienced more frequent and larger wildfires. These fires affect livestock forage, the sagebrush/grasses/forbs mosaic that is important for many wildlife species (e.g., the greater sage grouse (Centrocercus urophasianus)), post-fire flammability and fire frequency. When a sagebrush, especially a Wyoming big...

Timber is frequently salvage-logged following high-severity stand-replacing wildfire, but the practice is controversial. One concern is that compound disturbances could result in more deleterious impacts than either disturbance individually, with mechanical operations having the potential to set back recovering native species and increase invasion by non-native species. Following the 2002 Cone ...

Worldwide, the landscape homogeneity of extensive monocultures that characterizes conventional agriculture has resulted in the development of specialized and interacting multitrophic pest complexes. While integrated pest management emphasizes the need to consider the ecological context where multiple species coexist, management recommendations are often based on single-species tactics. This app...

Current paradigm suggests that spatial and temporal competition for resources limit an exotic invader, cheatgrass (Bromus tectorum L.), which once established, alters fire regimes and can result in annual grass dominance in sagebrush steppe. Prescribed fire and fire surrogate treatments (mowing, tebuthiuron, and imazapic) are used to reduce woody fuels and increase resistance to exotic annuals,...

................................................................................................................................ ii ACKNOWLEDGEMENTS .......................................................................................................... iv CHAPTER 1. BACKGROUND ................................................................................................... 1 History and Ec...