Spectacular Sumacs

Unfortunately, common names and misidentification get some plants in trouble. Sumacs are among those often persecuted. Our native sumacs in the genus Rhus are members of the cashew family, Anacardiaceae. They share this family with several familiar trees: cashew (Anacardium occidentale), mango (Mangifera indica), pistachio (Pistacia spp.), smoketree (Cotinus spp.), and the pernicious poison sumac (Toxicodendron vernix).

The desirable sumacs in Pennsylvania include staghorn sumac (Rhus typhina), smooth sumac (Rhus glabra), winged sumac (Rhus copallinum), and fragrant sumac (Rhus aromatica). They all share characteristics that make them valuable additions to our landscape. All are found in USDA Plant Hardiness Zones 4 through 8. Sumacs are happiest growing in areas with full sun to partial shade. They are not fussy about soil, growing in well-drained soil, and are drought-tolerant in urban, suburban, or rural environments. They spread by underground suckers, making them ideal for hedges, visual screens, and naturalizing. Sumacs also tolerate salt spray and salt runoff, so roads and walkways do not limit their placement.

Sumacs' large compound leaves open to bright green foliage in early spring. In late spring, clusters of creamy white to yellow flowers appear at the tips of branches. I've seen honey bees, native bees, butterflies, and even hummingbirds gathering nectar and pollen from the small blossoms. Native sumacs are dioecious, meaning that their male and female flowers are borne on separate plants. As the summer progresses, plants with female flowers bear clusters of small red fruits called drupes. These red fruits make a delicious tea or lemonade-like beverage. Later, songbirds examine the clusters for insects hidden among the nooks and crannies. Wildlife feeds on the seeds as winter progresses.

In early autumn, the long, compound bright green foliage of sumacs becomes brilliant shades of orange, scarlet, and crimson. During the winter, snow outlines the branches.

Perhaps the most familiar sumac is staghorn sumac with its fuzzy branches like a deer's antlers in velvet. It has a less commonly found relative, smooth sumac, that does not have fine hairs on its branches. Both grow up to 20 feet tall. For your yard, consider a variety of staghorn sumac called Tiger Eyes® (Rhus typhina 'Bailtiger') with golden, deeply cut leaflets. It grows more slowly than the species and is shorter, topping at 6 to 10 feet, so it is better suited for many home landscapes. Its striking, glowing foliage makes up for its smaller stature.

Winged or shining sumac is a small tree or shrub in Pennsylvania. The leaves are shinier than those of staghorn sumac. Its identifying characteristic is the wings along the central vein of the leaves.

My favorite sumac is the fragrant sumac, a naturally compact plant. Its spicy-citrus scented foliage makes it resistant to deer browse. It has only three leaflets. Its flowers and fruit clusters are small. A natural variety, 'Gro-Low', only reaches 1 to 2 feet tall, making it ideal along walkways. It spreads easily, making it perfect for erosion control on steep banks. A slightly taller variety, Lacette™, has finely dissected leaflets of three.

There are other plants, often called sumacs, that deserve their bad reputations. These are not in the genus Rhus. Stinking sumac is another common name for tree-of-heaven, Ailanthus altissima. This large landscape tree, purposely introduced from Asia, has become invasive. It is an old friend with the accidentally and newly introduced spotted lanternfly, Lycorma delicatula.

Perhaps the plant that gives the sumacs the worst reputation is the native shrub, poison sumac, Toxicodendron vernix. Its leaflet margins are entire (smooth), not serrated (toothed). Its flowers and white fruits are in loose clusters on the sides of branches, not the tips. Throughout my life, folks have shown me uncomfortable rashes they attributed to poison sumac. While urushiol in the sap of poison sumac does cause severe dermatitis, the causative plant has almost always been misidentified. The harmless staghorn sumac is blamed. Its ubiquitous cousin, poison ivy, Toxicodendron radicans, is the common source of urushiol. Poison ivy grows almost everywhere, while poison sumac is an obligate wetland plant. Rarely do folks venture into poison sumac's soggy habitat of open swamps, calcareous marches, and rich fens. One really must go out of one’s way to encounter poison sumac.

Take a moment to rethink the sumacs! Sumacs can be a beautiful and desirable addition to your landscape. Native plant nurseries stock sumacs; you may also find them in garden centers, especially the Tiger Eyes®, Lacette™, and 'Gro-low' varieties.