Ranunculus is a large genus of about 600 species of
flowering plants in the family Ranunculaceae. Members of the genus are
known as buttercups, spearworts and water crowfoots. The familiar and
widespread buttercup of gardens throughout Northern Europe (and introduced
elsewhere) is the creeping buttercup Ranunculus repens, which has
extremely tough and tenacious roots. Two other species are also
widespread, the bulbous buttercup Ranunculus bulbosus and the much taller
meadow buttercup Ranunculus acris. Buttercups usually flower in
the spring, but flowers may be found throughout the summer, especially
where the plants are growing as opportunistic colonizers, as in the case
of garden weeds
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