Physocarpus (Ninebark) is a genus of about ten species of flowering plants in the family Rosaceae, native to North America (most of the species) and northeastern Asia (one species).

They are deciduous shrubs growing to 1-3 m tall. The name comes from the appearance of the bark, which is flaky, peeling away in many layers. The leaves are maple-like, palmately lobed, 3-15 cm long and broad, with an irregularly serrated margin. The flowers are white with five petals and numerous stamens, produced in corymbs. The fruit is a cluster of inflated follicles, which turn dry and brown and then split open to release the seeds.

• Physocarpus alternans (Dwarf Ninebark)
• Physocarpus amurensis (Asian Ninebark)
• Physocarpus bracteatus
• Physocarpus capitatus (Pacific Ninebark)
• Physocarpus glabratus
• Physocarpus malvaceus (Mallow Ninebark)
• Physocarpus monogynus (Mountain Ninebark)
• Physocarpus opulifolius (Common Ninebark)

External links

• USDA Plants Profile: Physocarpus
• Jepson Flora Project: Physocarpus
• Flora of China: Physocarpus