Rhus copallinum L.

Winged Sumac

© SRTurner

Family - Anacardiaceae

Habit - Shrubs or small trees, rhizomatous, dioecious, sometimes incompletely so.

Stems - Ascending, 1.5-6.0 m long, single or multiple, branching. Young branches densely hairy, becoming glabrous or nearly so with age, the older branches woody, with prominent lenticels.

	Stem and nodes.
© SRTurner

Leaves - Alternate, petiolate, pinnately compound, with 7-13 leaflets. Petioles 3-6 cm long, densely hairy, the rachis narrowly to broadly winged between leaflets (the wing interrupted where the leaflets are attached). Leaflets 3.0-8.5 cm long, 1.5-3.0 cm wide, sessile, broadly lanceolate to oblong, the margins entire or with a few teeth distally, the upper surface dark green, glabrous or nearly so except for the densely hairy main veins, shiny, the undersurface light green to grayish green, sparsely to moderately felty-hairy and with scattered, minute, reddish-brown glandular hairs. Terminal leaflet sometimes divided, abruptly contracted at base and appearing to have a petiolule.

	Leaf adaxial. The winging along the leaf rachis is characteristic, though variable.
© SRTurner

	Leaf abaxial.
© SRTurner

	Pressed leaf (adaxial).
© DETenaglia

	Pressed leaf (abaxial).
© DETenaglia

Inflorescence - Terminal, dense, ovoid panicles 12-18 cm long, 6-8 cm wide, the axis and branches tomentose.

	Inflorescence (staminate).
© SRTurner

Flowers - Sepals 5, basally fused, 0.8-1.1 mm long, ovate, bluntly to sharply pointed at the tip, moderately to densely hairy. Petals 5, 1.5-2.5 mm long, oblong, rounded at the tip, yellowish green. Stamens 5, erect, exserted, alternating with petals, the filaments white, to 1.5 mm long, the anthers ovoid, yellow-orange, 1 mm long. Styles 3. Ovary globose, tomentose to puberulent, 0.9 mm in diameter, unilocular.

	Staminate flowers.
© SRTurner

	Staminate flowers.
© DETenaglia

	Pistillate flowers.
© SRTurner

Fruits - Drupes 4-6 mm long, 4-5 mm wide, somewhat flattened, red, with dense, minute, stout, red glandular hairs and sparse to moderate, longer, white to colorless nonglandular hairs, the outer layer and resinous fleshy to waxy middle layer readily detachable from the smooth stone.

	Fruits.
© SRTurner

	In this species, older fruit clusters tend to droop.
© SRTurner

Flowering - May - November.

Habitat - Glades, upland prairies, degraded prairies, savannas, mesic to dry forest openings, old fields, railroads, roadsides, open, disturbed areas.

Origin - Native to the U.S.

Other info. - This species occurs throughout Missouri except for the far northern counties of the state. Missouri lies near the westernmost extent of the plant's range, which extends southward and eastward to the respective coasts. It is easily recognized by its shrubby habit, odd-pinnate leaves, and the winging found along the leaf rachis. This winging can vary from narrow to fairly broad. The leaves turn a brilliant crimson red in the fall. The species can also be recognized during the winter by its fruit clusters, which are unique in the genus in that they droop downward in old plants.

Winged sumac "berries" have been used to make a pleasantly tart tea not unlike lemonade. People who are highly allergic to poison ivy should sample this beverage cautiously, since the two plants belong to the same family and tiny traces of urushiols can be present in sumac tissues. Like other members of the genus, this plant was used by Native Americans to treat ailments such as dysentery and mouth sores.

Rhus copallinum is an example of a native species which can become invasive under certain conditions. Degraded prairies are sometimes overrun with the shrubs as a first stage toward conversion to a wooded environment. Excessive soil nitrogen is one factor implicated in this pathology, which is a focus of current ecological studies. The issue is of concern due to the dwindling amount of high-quality prairie habitat remaining in Missouri.

Photographs taken at Dave Rock Conservation Area, St. Clair County, MO., 7-27-00, at Logan Creek, Reynolds County, MO, 7-3-04 (DETenaglia); also at Crowley's Ridge Conservation Area, Stoddard County, MO, 7-17-2009, Hughes Mountain Natural Area, Washington County, MO, 10-29-2018, Meramec Conservation Area, Franklin County, MO, 7-14-2020, Taum Sauk State Park, Iron County, MO, 8-04-2020, and Shaw Nature Reserve, Franklin County, MO, 7-10-2021 (SRTurner).