Securigera varia (L.) Lassen (Family: Fabaceae)
Origin: Crown vetch is native to the Mediterranean region of Europe, southwest Asia, and northern Africa. It was introduced to the United States in the 1950s for erosion control and is still sometimes sold as an ornamental.
Description: Crown vetch is a perennial herb of the pea family (Fabaceae) whose creeping stems can grow to be up to 6 feet long. Its alternate, pinnately compound leaves consist of 9-25 oblong leaflets, and its flowers are pink to purple to white, irregular, and borne in heads similar in appearance to large clover flower heads. Fruits are narrow, flattened pods which are 2-3 inches long and occur in crownlike clusters.
Distribution: Crown vetch prefers sunny, open areas. It tolerates drought, periods of heavy precipitation, and temperatures down to -28° F. It is commonly found along roadsides and right-of-ways, in open fields, and on gravel bars along streams.
Problem: Crown vetch seeds prolifically and spreads quickly by rhizomes. It is prone to forming large monocultures. It grows over and shades native vegetation and can even climb over shrubs and small trees. It is nitrogen-fixing and can alter the nitrogen cycle of plant communities that may depend on infertile soils.
Control: Crown vetch can be controlled by mowing in late spring for several successive years. For chemical control, use a 2% a.i. solution of triclopyr or a 1-2% a.i. solution of glyphosate applied to foliage in early spring.
USE PESTICIDES WISELY: Always read the entire pesticide label carefully, follow all mixing and application instructions and wear all recommended personal protective gear and clothing. Contact your state department of agriculture for any additional pesticide use requirements, restrictions or recommendations.