Crown vetch is a perennial legume that has creeping stems which form dense mounds of vegetation. Each of the compound leaves bears fifteen to twenty-five leaflets. Pea-like pink and white flowers are produced in early summer and develop into narrow, leathery seed pods. Introduced to the United States for use in erosion control, crown vetch is very widely planted along roadsides in Indiana. Since it has a tap root rather than fibrous roots, it actually provides little erosion control. It spreads rapidly through seed and by underground stems, invading many of our open natural areas like prairies and savannas. Note – do not buy, sell, or plant crown vetch. <www.invasive.org>
In 100 Years of Change in the Distribution of Common Indiana Weeds by William and Edith Overlease (2002) reported that crown vetch was not found in Indiana in 1899 (Coulter’s Catalogue of Indiana Plants) and in 1940 (Deam’s Flora). However, in 2002 Overlease observe crown vetch spreading in all 92 counties in Indiana. Crown vetch was commonly spread from road shoulder plantings.