Rhus glabra L.

by Manny Kropf, Native Plants Class
Common names:
Smooth sumac, common sumac, scarlet sumac (5, 7, 12).
Family: Anacardiacea
Synonymy: Rhus borealis Greene, Rhus calophylla Greene, Rhus glabra L. var. laciniata Carr., Rhus glabra L. var. occidentalis Torr. (13)
Etymology: The genus Rhus is the name for a bushy shrub. The epithet glabra refers to the smooth stems and leaves (7).

Identification
Growth form:
Usually a dense thicket-forming shrub from 1 m to 2 m tall, but may become a small tree, 7 m tall (4, 12).
Roots: Depended almost exclusively on root suckering for reproduction (14).
Stem: Stems are red brown to purplish, 4-6 mm in diameter, with prominent gray lenticels. Twigs and petioles are smooth, hairless and glaucous (2, 11).
Leaves: Leaves are alternate, pinnately compound, smooth, hairless and elliptic to narrowly ovate. Leaves are sharply serrated to occasionally sub entire, with the upper surface dark green and lustrous, and the lower surface whitened. Leaves turn bright red in the fall (2, 11, 12). There are typically 15-23 leaflets per leaf; leaflets are 7-9 cm long and 2-3 cm wide (11).
Inflorescence/flowers: Inflorescences are loose terminal pyramidal panicles 5-15 cm long (2, 11). Male and female flowers are in separate groups on different trees in many flowered, elongated, dense clusters. Flowers have 5 sepals and 5 white to yellowish green pedals, with the male flowers having 5 stamens and the female flowers a single pistil (3, 5).
Fruit: The fruit is a reddish brown, fleshy, elliptic or elliptic-ovate, 4-5 mm diameter berries covered with short velvety hairs (2, 7, 12). Each fruit contains one flattened stone and seed (3, 12).
Similar species: Rhus michauxii is a rare plant species of the southeastern U.S. that is very similar to Rhus glabra, with differences occurring in their DNA only (1). The fruits of Rhus aromatica Aiton are very similar to those of Rhus glabra, except Rhus aromatica has 3 leaflets and yellow flowers (7, 8, 9).

Ecology
Life history:
Short lived pioneer with a life span of about 30 years. Clones from root suckering can live longer (14).
Native/introduced: Native (2, 13).
Photosynthetic pathway: C3 (10).
Phenology: In the southwest sumac flowers from June to August (5, 12). Fruits ripen from September to October and are dispersed by birds and mammals (12) Fire typically promotes seed germination (14).
Distribution: Widespread throughout the United States, southern Canada and northern Mexico (10). In Arizona sumac is found in rich soils and along roadsides from Apache County to Coconino County, south to Cochise and Pima County, and at elevations from 5000 to 7000 feet (5, 6, 11).

Uses
Wildlife: Sumac is an important food for white tailed deer, rabbits and 32 species of birds (4, 12). Native Americans: All parts of the sumac have a wide range of uses including roots for dye, stems for basketry, leaves for tanning and smoking, berries for tea and lemonade, and the roots, shuts, and berries for food. Medicinally all parts of the sumac were used as an astringent to stop bleeding and for renal disorders. Sumac sticks were chewed to prevent tooth decay and to treat sore mouths and tongues (4, 7).

References
1. Burke, J. M. and Hamrick, J. L. 2002. Genetic Variation and Evidence of Hybridization in the Genus Rhus (Anacardiaceae). J. of Heredity. 93:37-41.

2. Cronquist, A., Holmgren, N. H., and Holmgren, P. K. 1997. Intermountain Flora: Vascular Plants of the Intermountain West, U.S.A., Vol. 3, Part A, Columbia University Press, New York.

3. Elias, T. S. 1980. Trees of North America. Van Nostrand Reinhold Company, New York.

4. Elmore, F. H. 1976. Shrubs and Trees of the Southwest Uplands. Southwest Parks and Monuments Association, Tucson, AZ.

5. Epple, A. O. 1995. A Field Guide to the Plants of Arizona. Flacon Publishing, Helena, MO.

6. Kearney, T. H. and Peebles, R. H. 1964. Arizona Flora. University of California Press, Berkeley and Los Angeles, CA.

7. Kindscher, K. 1987. Edible Wild Plants of the Prairie. University Press of Kansas, Lawrence, KA.

8. Li, X., Baskin, J. M. and Baskin, C. C. 1999. Comparative morphology and physiology of fruit and seed in the two shrubs Rhus aromatica and R. glabra (Anacardiaceae). American J. of Botany. 86:1217-1225.

9. Li, X., Baskin, J. M. and Baskin, C. C. 1999. Contrasting Soil Seed-bank Dynamics in Relation to Local Recruitment Modes in Two Clonal Shrubs, Rhus aromatica Ait. and R. glabra L. (Anacardiaceae). The American Midland Naturalist. 142:266-280.

10. McCarron, J. K. and Knapp, A. K. 2001. C3 woody plant expansion in a C4 grassland: are grasses and shrubs functionally distinct? American J. of Botany. 88:1818-1823.

11. Stephens, H. A. 1973. Woody Plants of the North Central Plains. University Press of Kansas, Lawrence, KA.

12. Vines, R. A. 1960. Trees, Shrubs and Woody Vines of the Southwest. University of Texas Press, Austin, TX.

13. http://plants.usda.gov/cgi_bin/refer.cgi. 2002. Plants: Source and Reference. The U.S. Department of Agriculture.

14. http://www.treeguide.com/Species.asp?Species|D=910. TreeGuide: Species Details. Athenic Systems.