What It Is
Sumacs are plants from the genus Rhus that grow around the world, with over a dozen true sumac species in North America. Despite the name, poison sumac is included with species including poison oak and poison ivy in the Toxicodendron genus. Sumac’s dried, ground fruit is a common spice in Mediterranean and Middle Eastern cooking, and the dried berries can also be used to made a lemonade-like beverage.
There is significant variety in size and form in the genus, but Rhus glabra, smooth sumac, and Rhus typhina, staghorn sumac, are two of the larger forms that can be grown as small trees. Though they are nearly identical in appearance and growing conditions, Rhus glabra is native across North America, including the Spokane region, while Rhus typhina is native only to the eastern half of the continent. Both grow naturally as large, multi-stemmed shrubs forming large colonies, but a bit of yearly pruning will keep them trained into a tree form.
Why to Grow It
Smooth sumac and staghorn sumac are fantastic plants for four-season interest. In a garden setting, sumac’s bare lower trunks offer architectural interest in spring and summer, while its feathery compound leaves create a dense screen of green foliage. Fall and winter are its real time to shine, though. Large conical seedheads mature throughout the summer, arriving at a deep rust color by autumn.The contrast with the green foliage is stupendous, but even better is the brilliant orange-red fall color. Sumac is one of the first plants to change, making it easy to identify along roadsides and in its native habitat. After the leaves drop, the seedheads persist through the winter, offering a bright spot of color as well as important food for wildlife.
Where to Put It
Sumac is an excellent plant for naturalizing marginal areas, as it does well in extremely poor soils and is very drought tolerant. It can often be seen on steep hills or along the roadside, as it is also resistant to erosion and pollution. In a residential landscape, a single-trunked tree will grow to about 15’ high with a slightly wider spread. Sumac will take some shade, but prefers full sun, and has low water requirements. Because the foliage is massed towards the top of the plant, sumac can be complemented with low- to medium-height perennials and shrubs around it to provide a visual balance.