Identification
Perennial; Flowers are borne in an umbel and are surrounded by yellowish-green bracts. These bracts turn yellow in late May making them easier to identify. Extensive root system.
Economics
Reduces rangelands to a monoculture. Forage carrying capacity may be reduced by 50 to 75% once established requires extensive program to contain or control.
Chemical Control
Residual herbicides are preferable due to the weed's ability to regenerate from the roots. In all cases repeat applications on an annual or semi-annual basis for 5 years plus will be necessary.
Biological Control
Several agents, mainly flea beetles, have been established in Eastern Oregon. The flea beetles defoliate the plant and bore into the crowns. Availability of agents should improve in the coming years.
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Field crop plant health challenges
