Creeping buttercup (Ranunculus repens) is the most common species of buttercup.  Level of control will vary with species.

Propagation

Buttercups establish from the seedbank in new grass leys, and where gaps occur in the sward. Once established, creeping buttercup can spread by stolons.

Impact on Grazing

Creeping buttercup is often a severe problem in horse paddocks, where close grazing tends to open the sward. It is not generally grazed by stock, but animals will eat it when there is insufficient grass available. Fresh buttercup can be toxic to livestock when eaten in large quantities, but is palatable when in hay. Typically grazing animals rarely consume buttercups if other forage is available.