Dalea formosa Torr.

by Kirsten Larsen, Native Plants of Arizona 2004
Common names: Featherplume, feather dalea (1,2,3,4,9), feathery dalea (3), indigo bush, pea bush (4), feather indigo (6).
Family: Fabaceae (1) (alt. Leguminosae) (10)
Synonymy: Parosela formosa Vail (7)
Etymology: Dalea honors the English botanist Samuel Dale; formosa refers to the “pretty flowers” (2) or meaning finely formed, handsome, beautiful, shapely, in reference to flowers (8,9).

Identification
Growth form: Shrubby, stems 25-60 (70) cm. tall, intricately branched (3,4,6,7).
Roots:
Stem: Divaricately branched, rigid (8), glabrous (3), bark light gray to brown (9), thorns none (7).
Leaves: Odd-pinnately compound, dark green (4), leaf seldom more than 1 cm. long, sessile or very short petiolulate (9), leaflets 7-11(15) narrowly obovate, 1-3 mm. long, thick and often conduplicate, glaborous, dotted with glands (3).
Inflorescence/flowers: Flowers in 2-10 flowered head-like spikes (3), axis 1-2 mm. long (7). Corolla rose-purple, free banner sometimes yellowish or cream-colored (4) mostly on claw, blade of banner 2-4 mm. long, claw about as long, blades of the keel and wings longer but the claws shorter. Wings and keel attached to 9-10 stamens (7,9), monadelphous (9). Calyx long villous, campanulate tube 3-4 mm., longitudinally ribbed, the lobes 5.16-5.40 in. long, ovate-attenuate bract subtending each flower, glabrous on back, silky on margins, glandular (3,7,9).
Fruit: Obovate flat pod, 3 mm., pillose on apical margin, (6,7), glandular-dotted (3,6), enclosed in calyx (7,9) indehiscent, 1-2 seeded (9) .
Similar species: There are 58 species in the genera Dalea (10). Dalea formosa is distinct from other species of Dalea due to the rose-purple color of the flower and long villous lobes on the calyx.

Ecology
Life history: Low perennial woody shrub to subshrub (2,3,10).
Native/introduced: Native to the Southwestern United States and northern Mexico(10).
Photosynthetic pathway:
Phenology: Flowers April to June (3) sometimes March to September (4, 5).
Distribution: Colorado, southern Utah, western Texas and Oklahoma, New Mexico, Arizona (2,3,5), and northern Mexico (5). 2,000 to 6,500 (7,000) feet elevation (3,4,5,6) on dry, rocky hillsides (2,6), mountains, dry plains (4), mesas, southern canyons (6). Gravelly or rocky slopes in upper Mojavean, Arizona, and Chihuahuan deserts, desert grasslands, and southwestern oak woodland. In Arizona below the Mogollon Rim from Yavapai County southeastward to eastern Pima, Santa Cruz, and Cochise counties.

Uses
Browsed by deer and lightly by livestock (2,4,7), kangaroo rats eat the seeds (8), pollinated by bees (4). Pueblo Indians dried the flowering branches for a sweet tea to relieve aches and growing pains. Hopi used as a remedy for influenza and viral infections (a “cold” herb for fevers) (6). The Acoma and Laguna Indians infused leaves as an emetic before breakfast, and to increase endurance and long wind for runners, as well as using it for firewood. The Jemez Indians used decoction of leaves as a cathartic (11). Sometimes used as an ornamental (7).

References

1. Retrieved [November, 12, 2004], from the Integrated Taxonomic Information System on-line database, http://www.itis.usda.gov.

2. Johnson, F. L., and B. W. Hoagland. 1999. Catalog of the Woody Plants of Oklahoma: Descriptions and Range Maps. (http://www.biosurvey.ou.edu/shrub/dafo.htm). University of Oklahoma and Oklahoma Biological Survey, Norman, Oklahoma 73019 USA.

3. McDougal, W.B. 1973. Seed Plants of Northern Arizona. The Museum of Northern Arizona. Flagstaff, Arizona.

4. Epple, A. O. 1995. A Field Guide to the Plants of Arizona. Falcon Publishing. Helena, Montana.

5. Kearney, T. H., R. H. Peebles, and collaborators. 1960. Arizona Flora 2nd Edition. University of California Press, Berkeley and Los Angeles, California.

6. Carter, J. L. 1997. Trees and Shrubs of New Mexico. Johnson Books, Boulder, Colorado.

7. Benson, L. and R. A. Darrow. 1981. Trees and Shrubs of the Southwestern Deserts (3rd ed). University of Arizona Press, Tucson.

8. Elmore, F. H. 1976. Shrubs and Trees of the Southwest Uplands. Southwest Parks and Monuments Association, Globe, Arizona.

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

10. USDA, NRCS. 2004. The PLANTS Database, Version 3.5 (http://plants.usda.gov). National Plant Data Center, Baton Rouge, LA 70874-4490 USA.

11. Moerman, D. 2003. Native American Ethnobotany Database (http://herb.umd.umich.edu/). University of Michigan, Dearborn, MI 48198 USA.