For the last fifty years, meadow foxtail (Alopecurus pratensis L.) has been
invading native flood meadows throughout the Harney Basin in southeastern Oregon.
The expansion of this grass species has been the result of its broad climatic requirements
and ability to withstand drought while thriving in saturated soil conditions for...
Many streams in eastern Oregon are listed as water quality impaired on the
basis of water temperature. However, it is often difficult to predict water
temperature for these streams even if there are no anthropogenic impacts. We
measured air and water temperature and stream characteristics on three Type C and...
Crested wheatgrass (Agropyron cristatum [L] Gaertm), an introduced bunchgrass, has been seeded on over 5 million hectares of degraded rangeland in western North America because it establishes more readily than native bunchgrasses. Because crested wheatgrass stands are associated with native species displacement and low biological diversity, there is substantial interest...
Seasonal trends in forage quality and production were studied on improved
and unimproved portions of four plant communities in eastern Oregon. The range
improvements consisted of seeding and/or thinning. Improvement doubled forage
production on the lodgepole pine site (thinned but not seeded), tripled production
on the grassland and moist meadow...
AUTHORS: TonySvejcar, former graduate student of Oregon State
University, Eastern Oregon
Since the late 1880's western juniper has expanded in range and
increased in density in sagebrush-bunchgrass, riparian, and forested plant
communities of the Pacific Northwest. Succession to western juniper
woodland has been shown to reduce the productivity and diversity of the
understory component, result in concentration of soil nutrients beneath...
In the Northwest Great Basin, aspen (Populus tremuloides) communities
uniquely contribute to the biodiversity of a semi-arid, sagebrush-dominated
landscape. In this same region, western juniper (Juniperus occidentalis) is
encroaching into aspen stands. This study determined the timing, extent, and some
of the effects of this expansion.
Aspen stands below 2,133...
Crested wheatgrass (Agropyron cristatum [L] Gaertm) has been seeded on more than 5 million hectares in
western North America because it establishes more readily than native bunchgrasses. Currently, there is
substantial interest in reestablishing native species in sagebrush steppe, but efforts to reintroduce native
grasses into crested wheatgrass stands have...
Western rangelands are currently under severe threat from exotic annual grasses. To successfully manage rangelands that are either infested with or susceptible to exotic annual grasses, we must focus on increasing resilience to disturbance and resistance to exotic annual grass invasion. Here, we present a fuel-based model and research framework...
Water potential, leaf conductance, growth, nitrogen
content, and seedling survival of Wyoming Big Sagebrush
(Artemisia tridentata ssp. wyomingensis) following
defoliation of the herbaceous understory were assessed
during two growing seasons. Precipitation was 107% and 63%
of the long-term mean (283 mm) in 1989 and 1990,
respectively, which presented an opportunity...