Pacific ninebark (Physocarpus capitatus) is a member of the rose (Rosaceae) family and native to the Pacific Northwest. The shrub is erect, but it can spread, and typically grows 8-10 feet tall and 4-7 feet wide. Its bark is very distinct – it grows in layered pattern that peels off in long, thin layers hinting at its common name.
Pacific ninebark is a deciduous shrub with alternate leaves that are lobed, double-teethed, and deep-veined. The leaves are dark, shiny green at the top of the shrub and a lighter green at the bottom, with tiny star-shaped hair visible with a hand lens. Ninebark has clusters of small, white flowers, each with 5 petals and pink-tipped stamens, that bloom from April-July. The fruit of the Pacific ninebark is a red pod which dries out and splits open to release the long shiny yellowish seeds. The name of the shrub comes from the Greek words physa, or “bladder,” and carpos, meaning “fruit.”
The Native American tribe, Nuu-chah-nulth, used the branches to make bows for children, along with knitting needles and other small items. Other coastal tribes made a medicinal tea from pealed branches to use as a laxative and to treat sores.
Ninebark prefers partial shade but tolerates full sun and does well in wet areas with course, medium, or fine semi-acidic soil. The Conservation District has plenty of streams and riparian areas that are great habitats for Pacific ninebark. The shrub’s fibrous roots and ability to grow quickly from live cuttings make it a great option for streambank and slope stabilization. In addition, its shrubby form provides good nesting spots for birds, especially since small mammals, deer, and elk tend to avoid the ninebark. Finally, Pacific ninebark’s white flowers, brown pealing bark and great fall color makes it a great looking addition to the landscape.
By Dylan Carlson, WMSWCD intern (Summer, 2017)