chrysanthemum

Any of the ornamental plants that make up the genus Chrysanthemum, in the aster family (Asteraceae). The genus includes about 100 species native primarily to subtropical and temperate areas of the Old World. Cultivated species, often called mums, have large flower heads; those of wild species are much smaller. Most species have aromatic, alternate leaves. Some have both disk and ray flowers in the heads; others lack ray flowers. Costmary (C. balsamita), marguerite, Shasta daisy (hybrid forms of C. maximum), florists' chrysanthemum (C. morifolium), feverfew (C. parthenium), corn marigold (C. segetum), and tansy are popular garden plants. Feverfew is used in insecticides; feverfew and tansy were formerly used in medicines.

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