Crataegus, commonly known as hawthorn, is a genus of several hundred species of shrubs and trees in the family Rosaceae. Native to temperate regions of the Northern Hemisphere in Europe, Asia, North Africa, and North America, it has been introduced in many other parts of the world where it can be an invasive weed.

Hawthorns are all small, bushy trees growing on a single trunk. In European species, the alternate leaves are deeply lobed, from three to nine lobes, while in American and Asian species, the leaves are oval and straightforward. The grey bark is fluted and rough. The white, pink, or red flowers, depending on the species or cultivar, with five petals, bloom in May and are grouped in corymbs.

Rosaceae, the rose family, is a medium-sized family of flowering plants, including 4,828 known species. The family Rosaceae includes herbs, shrubs, and trees. Most species are deciduous, but some are evergreen. They have a worldwide range, but are most diverse in the Northern Hemisphere.

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