(Ranunculus repens L.)
Family: Buttercup Family (Ranunculaceae)
Native Range: Eurasia
Creeping buttercup is an herbaceous perennial that grows along the ground. Plants have thick stems and may be as much as 1 foot tall. Leaves and stems are usually hairy. Leaves at the base of the plant have long petioles; leaves that are higher on the stem have shorter petioles or lack petioles. The leaves, which are dark green with white, blotchy markings, are divided into nine sharply toothed segments (technically, each leaf is divided into 3 leaflets, and each leaflet is subdivided into three subleaflets).The central leaflet has a stalk. Leaves range from ½ to 3 1/3 inches long and up to 4 inches wide. The plant flowers from May through July or August. Its bright yellow flowers are about 1 inch in diameter, grow singly on long stalks, with 5 (occasionally 7) petals and spreading sepals. Creeping buttercup prefers moist fields and meadows where the soil is rich; it also grows along roadsides and in moist sand or gravel.
Creeping buttercup has long stolons, runners that can produce new roots and flowering stems. It also produces tiny (about 0.1 inch in diameter) spherical fruits (achenes) that have sharp edges and a short, curved beak at the end. The fruits are dispersed by hooking onto passing birds and mammals, or are carried by wind or water.
Creeping buttercup is similar to several other species of buttercup (Ranunculus spp.); it may be mistaken for the native swamp buttercup (Ranunculus hispidus) or a few other non-native buttercups, such as the tall buttercup (Ranunculus acris). The white markings on the leaves and its creeping, densely colonial growth form help to distinguish creeping buttercup.
Creeping buttercup grows rapidly and can form thick carpets that crowd out native plants, particularly in wet soils. It also depletes potassium in the soil, reducing the nutrients available for native plants. Creeping buttercup can be toxic to grazing animals, but livestock generally avoid it because it has a bitter taste.
Native to Eurasia, Creeping buttercup may have been introduced into to North America from England as an agricultural weed. It is now found throughout New England and most of the other states.
Sources and Links:
Invasive Plant Atlas of New England (IPANE)
USDA Plants Database
Noxious Weeds of King County, WA