Published May, 2014

Common name: Buttercups
Scientific name: Ranunculus species

Life Cycle: Perennial
Origin: United States
Poisonous: Yes

Buttercup is the common name for several Ranunculusspecies distributed across much of the United States. Smallflower buttercup (Ranunculus abortivus), bulbous buttercup (Ranunculus bulbosus), tall buttercup (Ranunculus acris), and creeping buttercup (Ranunculus repens) are the most commonly occurring species. They can be difficult to identify depending on the growth stage. All buttercups are characterized by bright yellow flowers and most frequently grow in overgrazed pastures. Buttercups might overwinter as corms but primarily reproduce through seeds. In Kentucky, seeds germinate in early March and plants flower from April through June.

Buttercups can be poisonous to horses, but the plants are not palatable and animals usually do not eat them. The toxin is found in the leaves and stems, and flowering plants contain more of the toxin than younger plants.

Mowing is usually ineffective for controlling buttercups; however, buttercups are easily controlled with several herbicides. Consult a local Kentucky Cooperative Extension Service office for a list of herbicidal controls in your area.

William W. Witt, a retired professor and researcher in the University of Kentucky College of Agriculture’s Plant and Soil Science Department, provided this information.