|Mcdaniel, Kirk -|
Submitted to: Invasive Plant Science and Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 16, 2010
Publication Date: January 2, 2011
Citation: Ralphs, M.H., Mcdaniel, K. 2011. Broom snakeweed (Gutierrezia sarothrae): Toxicology, ecology, control, and management. Invasive Plant Science and Management. 4(1):125-32. Interpretive Summary: Broom snakeweed is an invasive native sub-shrub that is widely distributed across rangelands of western North America. In addition to its invasive nature, it contains toxins that can cause death and abortions in livestock. It establishes in years of above average precipitation following disturbance by fire, drought or overgrazing. This allows widespread even-aged stands to develop that can dominate plant communities. Although its populations cycle with climatic patterns, it can be a major factor impeding succession of plant communities. Snakeweed can be controlled with prescribed burning and herbicides, however a weed-resistant plant community should be established and/or maintained to prevent its reinvasion. Proper grazing and management to maintain competitive grasses is essential for suppression of this invasive weed.
Technical Abstract: Broom snakeweed is a native weed that is widely distributed on rangelands of western North America. Following disturbance from overgrazing, fire or drought, it can increase to form near monocultures. Dense snakeweed stands suppresses desirable forage production, but it is also toxic, and can cause abortions in livestock. This paper reviews broom snakeweed toxicology, and compiles recent information on its seed ecology, population cycles, control and management. Snakeweed germinates from seed that are partially buried near the soil surface and the soil surface must remain saturated for several days. Disturbance from fire or grazing reduces competition from other plants, allowing large expanses of even-aged stands to establish and dominate plant communities. Snakeweed can be controlled by prescribed burning and herbicides. However, a weed-resistant plant community should be established to prevent or minimize its reinvasion. Managing to maintain the dominant competitive grasses in the respective plant communities can prevent snakeweed dominance.