bird cherry (subgenus)

The bird cherries are a subgenus of the genus Prunus, characterised by having deciduous leaves, flowers 12-30 together on slender racemes produced in late spring well after leaf emergence, and small, sour fruit usually only palatable to birds, hence the name. They are native throughout the temperate Northern Hemisphere. Bird cherry is sometimes used as a food plant by Lepidoptera species including Brimstone Moth.
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