Yellow sweetclover is an introduced plant to North America. It is widespread in distribution, occurring in every state (USDA, 2014). Until recently it was a common addition to road side re-vegetation mixes as it establishes easy on disturbed sites and helps fix nitrogen in the soil.
It is a member of the pea family and completes its short life cycle as either an annual or a biennial. The yellow or white flowers occur prolifically on the many flowering stems. As with all members of the pea family the small flowers are bisymmetrical. The leaves occur in groups of three, like alfalfa leaves, but are comparatively smaller and narrower. Yellow sweetclover has a stout taproot. The plant has a generally sweet fragrance until later in the season when it cures out and has a sour smell.
Sweetclover can colonize disturbed sites and move into natural areas; it also can compete for resources with more desirable native vegetation. At the same time, it is an excellent resource for pollinators. Birds use the plants as cover and also eat the seeds. Wildlife commonly browse sweetclover as a forage especially early in the season when it has good nutritional value.
USDA, NRCS. 2014. The PLANTS Database (http://plants.usda.gov, 18 March 2014). National Plant Data Team, Greensboro, NC 27401-4901 USA.