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Crataegus ( //), commonly called hawthorn or thornapple, is a large genus of shrubs and trees in the rose family, Rosaceae, native to temperate regions of the Northern Hemisphere in Europe, Asia and North America. The name hawthorn was originally applied to the species native to northern Europe, especially the Common Hawthorn C. monogyna, and the unmodified name is often so used in Britain and Ireland. However the name is now also applied to the entire genus, and also to the related Asian genus Rhaphiolepis. They are shrubs or small trees, mostly growing to 5–15 metres (16–49 ft) tall, with small pome fruit and (usually) thorny branches. The most common type of bark is smooth grey in young individuals, developing shallow longitudinal fissures with narrow ridges in older trees. The thorns are small sharp-tipped branches that arise either from other branches or from the trunk, and are typically 1–3 cm long (recorded as up to 11.5 centimetres (4.5 in) in one case). The leaves grow spirally arranged on long shoots, and in clusters on spur shoots on the branches or twigs. The leaves of most species have lobed or serrate margins and are somewhat variable in shape. The fruit, sometimes known as a "haw", is berry-like, but structurally a pome containing from 1 to 5 pyrenes that resemble the "stones" of plums, peaches, etc. which are drupaceous fruit in the same subfamily.