نتایج جستجو برای: bromus sewerzowii
تعداد نتایج: 1400 فیلتر نتایج به سال:
Within the oak woodlands of California there is often a distinct shift in the botanical composition between the open grassland and the herbaceous understory beneath oak canopy. Botanical sampling at two woodland sites indicated that the annual grass Bromus diandrus was dominant under deciduous blue oak canopy, while a congener, Bromus hordeaceus, was dominant in open grassland. We examined the ...
Woodland ecosystems of the world have been changed by land use demands, altered fire regimes, invasive species and climate change. Reduced fire frequency is recognised as a main causative agent for Pinus–Juniperus L. (piñon–juniper) expansion in North American woodlands. Piñon–juniper control measures, including prescribed fire, are increasingly employed to restore sagebrush steppe communities....
Widespread invasion by Bromus tectorum (cheatgrass) in the Intermountain West has drastically altered native plant communities. We investigated whether Elymus multisetus (big squirreltail) is evolving in response to invasion and what traits contribute to increased performance. Seedlings from invaded areas exhibited significantly greater tolerance to B. tectorum competition and a greater ability...
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,...
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...
Stampfli A. 1992. Effects of mowing and removing litter on reproductive shoot modules of some plant species in abandoned meadows on Monte San Giorgio. Bot. Helv. 102: 85-92. Reproductive shoot modules have been counted in a permanent plot experiment on Monte San Giorgio (Southern Switzerland) since 1988. The 8 species presented here, including the dominant grass (Molinia arundinacea) and seven ...
Stampfli A. 1992. Effects of mowing and removing litter on reproductive shoot modules of some plant species in abandoned meadows on Monte San Giorgio. Bot. Helv. 102: 85-92. Reproductive shoot modules have been counted in a permanent plot experiment on Monte San Giorgio (Southern Switzerland) since 1988. The 8 species presented here, including the dominant grass (Molinia arundinacea) and seven ...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید