Birdsfoot Trefoil


bloom-fell, cat's-clover, crow-toes, ground honeysuckle, sheep-foot, hop o' my thumb, devil's-claw

Lotus corniculatus

Birdsfoot trefoil is a common perennial broadleaf plant in under-fertilized, minimal maintenance turfgrass sites. It is well distributed across Michigan and the Great Lakes Region. Trefoil is often found in culture with white clover and black medic. All three species host rhizobacteria that fix atmospheric nitrogen into plant available nitrogen making them particularly adapted to boundary and waste areas. Trefoil seems to be better adapted to slightly warmer soils than clover or medic and is often seen along curbs, driveways, and sidewalks. Trefoil becomes conspicuous in late-June when it produces large yellow flowers.

  • Crops Affected: turf


    The most effective cultural practices for members of the pea or bean family are routine nitrogen fertilization and consistent mowing. Together, these basic cultural practices will improve the growing conditions for the turf and reduce the presence of trefoil, clover, and medic. Frequent, heavy rains throughout the spring can leach nutrients from the rootzone creating favorable conditions for germination, establishment, and spread of trefoil, medic, and clover.

    Similar Species

    Birdsfoot trefoil resembles black medic with very dark green elongated leaflets. However, the center leaflet on black medic has a separate petioliole. The leaf margins on birdsfoot trefoil are entire whereas black medic and white clover have small serrations on the leaf margins. Birdsfoot trefoil's yellow flowers yellow resemble buttered popcorn or that of a snap dragon and are larger and less numerous than that of black medic.