Idaho OnePlan recommends the website of the
Idaho Weed Awareness
Campaign as the best resource for up-to-date information about
Idaho's noxious weeds, and their control.
Source for this page: Idaho's Noxious Weeds by Robert H. Callihan & Timothy W. Miller
Common crupina (Crupina vulgaris) is a native of the eastern Mediterranean region. Although it was introduced to North America (and first discovered in Idaho) less than 30 years ago, it has spread to over 60,000 acres in Idaho and moved into Oregon, Washington, and California. It is usually found on dry south slopes and pastures. It spreads by seed.
Common crupina is a winter annualPlant that germinates, flowers, seeds, and dies during one growing season that grows up to 4 feet in height. CotyledonsThe first leaflike structures that appear after germination; seed leaves (or seed leaves) exhibit a bright purple midribThe center and usually most prominent vein on a leaf. Leaves are simple and up to 6 inches long, entire near the base of the plant, lobed on the lower stem, and finely dissectedDeeply and repeatedly divided into smaller parts on the upper stem. Up to 5 narrow cylindrical seed heads are borne on the branch tips in midsummer. Flowers are pink to purple and are followed by dark seeds about the size of a kernel of wheat with a ring of black, bristly hairs at the point of attachment.
Common crupina is found exclusively in the Pacific Northwest and in central Idaho counties.
No biological control agents are available for common crupina, but herbicides are available that can control this weed.