Bromus tectorum

An area seeded to perennial grasses and an adjacent nonseeded area both within a burned Colorado pinyon/Utahjuniper (Pinus edulis Engelm./Juniperus osteosperma (Torr.) Little) com­ munity provided an opportunity to contrast frequency of plant species in the two treatments. Lower frequencies for cheatgrass (Bromus tectorum L.) and yellow salsify (Tragopogon dubius Scop.), which are introduced annuals, were found in the seeded

Many plants are adapted to an eroded landscape with a large proportion of virgin soil. Open and disturbed soils are today almost only restricted to agricultural fields with high loads of fertilizers. We conducted a pot experiment in order to investigate growth and nutritional constraints of one calcicole species, Anisantha (syn. Bromus) tectorum, and one calcifuge species, Rumex acetosella, in decalcified topsoil and recently exposed calcareous subsoil from a field experiment in sandy grassland. In the pot experiment we implemented one treatment where we limed topsoil with CaCO3 to the same amount as in subsoil.The subsoil had approximately 10% CaCO3 and both species grew less in this soil compared to the topsoil, which had less than 1% CaCO3. Germination rate of A. tectorum was higher in subsoil than in topsoil or limed topsoil. P fertilization of the limed topsoil counteracted the negative liming effect for A. tectorum, but only partly so for R. acetosella. P fertilization of subsoil increased the shoot biomass of A. tectorum, but not of R. acetosella. P concentration in plants was not reduced when growing on subsoil or limed topsoil compared to topsoil. The results show that lime addition may reduce the P availability also to calcicole species such as A. tectorum and we found indications for that Ca toxicity may be a causing factor for the calcifuge behavior of R. acetosella. The significance of the results for conservation management practices in sandy grasslands is discussed.

National Parks are hallmarks of ecosystem preservation in the United States. The introduction of alien invasive plant species threatens protection of these areas. Bromus tectorum L. (commonly called downy brome or cheatgrass), which is found in Rocky Mountain National Park (hereafter, the Park), Colorado, USA, has been implicated in early spring competition with native grasses, decreased soil nitrogen, altered nutrient and hydrologic regimes, and increased fire intensity. We estimated the potential distribution of B. tectorum in the Park based on occurrence records (n = 211), current and future climate, and distance to roads and trails. An ensemble of six future climate scenarios indicated the habitable area of B. tectorum may increase from approximately 5.5% currently to 20.4% of the Park by the year 2050. Using ordination methods we evaluated the climatic space occupied by B. tectorum in the Park and how this space may shift given future climate change. Modeling climate change at ...

Hydrothermal time models are often used to predict seed germination rates. In this study, soil water potential data from three resistance-type sensors (Colman cells, Watermark brand sensors, and Delmhorst gypsum blocks) and from a time-domain reflectometry (TDR) probe (Campbell Scientific 615) were input into a hydrothermal time model to predict seedling emergence in a growth chamber experiment for six desert

Cheatgrass (Bromus tectorum L.) has come to dominate millions of hectares of rangeland in the Intermountain western United States. Previous studies have hypothesized that one mechanism conferring a competitive advantage to this species is the ability to germinate rapidly at low ...

Grazing animals readily eat medusahead (Taeniatherum asperum [Sim.] Neuski) and cheatgrass (Bromus tectorum L.) during the short time when plants are green and succulent. Cheatgrass, the more important of the two, is a primary source of spring forage in the Great Basin. It is characterized by a short green-feed period, large yearly variations in yield, and declining forage quality as plants dry. However, cattle eat mature cheatgrass and gain as well as cattle grazing on matured perennial grasses growing in the same area.