Common smoketree (Cotinus coggygria) foliage explodes with color in May and June and its purplish-pink plume-like panicles (flower stalks) ignite the landscape throughout summer (Figure 1). Later, the native species, American smoketree (Cotinus obovatus) pops with spectacular yellow, orange, amber, red, and reddish-purple fall leaf color. Unlike most of Missouri's native trees, the American smoketree displays spectacular colors throughout the growing season. During winter, defoliated limbs are gnarled, providing an interesting feature in the landscape.

Figure 1 A specimen of common smoketree with its smoky panicles.

Figure 2 The green foliage of an American smoketree growing in St. Louis, Missouri.

Common smoketree is a non-native species introduced into North America in the mid-1600s. This species is similar to the American smoketree in growth habit and adapts to a range of soil types. Several cultivars of this species and hybrids of American and common smoketree have been developed with very large, "smokey" panicles. 'Pink Champagne', 'Purpureus', and 'Smokey Joe' are cultivars of common smoketree with blue-green summer foliage, tiny yellow flowers, and prolific panicles (Figure 2). 'Black Velvet', 'Flame', and 'Grace' are hybrids with dark purple foliage during the summer with puffy panicles up to one foot long and wide. 'Ancot', also known as Golden Spirit, has yellow to light green summer foliage that turns scarlet red in the autumn. Flowers have not been observed on Golden Spirit plants, nevertheless, pale pink panicles are conspicuous.

Figure 3 The tiny yellow flowers on a panicle of a purple-leaved common smoketree.

American smoketree is a hardy and adaptable small tree or shrub that grows to 15 to 30 feet at maturity. It thrives in full sun and in alkaline soils but tolerates slightly acidic and compacted soils. In the spring and summer, the foliage is blue-green in color and in May small, greenish flowers are produced on open, panicles that are 6 to 10 inches long (Figure 3). After the flowers fade, the purple hairs on the flower stalks become evident, resembling puffs of smoke. In autumn, the foliage of American smoketree turns an intense yellow-to-red color. American smoketree can be found growing in the wild in Polk, Taney, Ozark, and Douglas counties in Missouri. Trees for the home landscape can be purchased from nurseries that specialize in native plants.

Smoketrees are relatively drought-resistant and usually pest-free, requiring minimal care in the landscape. These plants can be trained and pruned to a tree form or left to grow as a multi-stemmed shrub. When needed, smoketrees can be pruned in late winter. Drastically pruning back stems of shrubs will temporarily reduce their size and promote the growth of colorful new foliage. However, the production of the billowy panicles will be sacrificed for the following growing season. When pruning, avoid contact with the wood sap by wearing gloves. The sap contains urushiol, which may cause a poison ivy-like, skin rash on humans with sensitivity to this compound. In contrast, leaves and panicles are safe to touch.