They face difficult decisions on how to use their limited resources. Land managers are tasked with controlling cheatgrass and medusahead, but resources are limited for invasive plant management. The conversion of a diverse native ecosystem to simple invasive grass-dominated ecosystems degrades the ecosystem processes leading to soil erosion, less water in the soil for plant growth, and changes in nutrient cycling, making a less productive land that is much harder to restore to what it was before the invasion. In addition, the thick thatch produced by annual grasses kills biological soil crusts (lichens, mosses and cyanobacteria) that once filled the soil interspaces between the native grasses and shrubs. In these areas, elimination of invasive annual grasses is very difficult because the limited number of remaining native plants are unable to produce seeds and seedlings that can compete with these invasive annual grasses. Plants native to the sagebrush landscape may not recover from disturbances that allow invasive annual grasses to over-run them, even decades later. Both species germinate in the fall and early spring, grow rapidly and in high numbers making them highly competitive with native species. in the mid- to late-1800's as a contaminant in seed and straw. Welty, USGSĬheatgrass originated in Europe or Eurasia and medusahead in the Mediterranean region. Visit Media to see details.Ĭheatgrass (Bromus tectorum) is the dominant exotic annual grass species on semi-arid rangelands of the western hemisphere. Sources/Usage: Some content may have restrictions.
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