(spirea), a genus of plants of the family Rosaceae. The plants are deciduous shrubs measuring 0.5–3 m tall. The alternate and simple leaves are usually dentate or serrate. The flowers, which are gathered in cymose, umbellate, or panicled inflorescences, are bisexual and have numerous stamens. The fruit is a follicle with tiny flat seeds.
There are about 100 species of spiraea, occurring in the northern hemisphere, mainly in the temperate zone. About 25 species are found in the USSR. The species S. media, which has smooth-margined or dentate leaves at the apex and white flowers in cymose inflorescences, grows in the northeastern part of the European USSR, in Southern Siberia, and in the Far East. It grows as part of the underbrush of arid forests and forms a dense cover on open slopes. S. salicifolia, which has sharply dentate leaves and pink flowers in pyramidal panicles, grows in Siberia and the Far East along riverbanks and in meadows and bogs. Both 5. media and S. salicifolia are ornamental shrubs commonly found in gardens and parks. Many other species and hybrids are cultivated as ornamentals.
V. N. GLADKOVA