Common name: Buttercups
Scientific name: Ranunculus species
Life Cycle: Perennial
Origin: United States
Buttercup is the common name for several Ranunculus species 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 occur in overgrazed pastures. Buttercups may overwinter (fleshy, bulblike stem bases) as corms but their greatest reproduction is 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 usually not eaten by animals. 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; they are easily controlled with several herbicides. Consult a local Cooperative Extension Service office for a list of herbicidal controls in your area.
Information courtesy of William W. Witt, PhD, a researcher in Plant and Soil Sciences at the University of Kentucky.