Other common names
Curveseed butterwort, little bur, testiculate buttercup
A small, 2‐ to 5‐inch tall plant that grows and flowers early in spring, bur buttercup produces stiff burrs that help spread this weed. It is toxic to livestock.
Small, yellow, with 2 to 5 petals. Blooms from late winter to early spring.
Grayish‐green, hairy, and attached at the base of the plant. Leaf blades look like fingers.
Short; extend outward from the base of the plant.
Forms many stiff, brown burrs. This is the point at which most people notice the plant.
Eurasia; naturalized throughout much of the western United States
Where it grows
Roadsides, vacant lots, in pavement cracks and other disturbed or unmanaged sites.
Winter annual (sprouts in fall and early winter)
Reproduces by seed
Bur buttercup should be controlled prior to seed formation. As this occurs very early in the spring, careful monitoring is needed to stop the spread of this weed.