SYNONYM INFORMATION

Coast indigo, scarlet pea and Texas indigo

Uses

Western indigo is used as a warm-season forage legume for livestock and deer forage in range seeding and pasture plantings. It can be used as revegetation of surface-mined soils, wildlife food and cover, range and pasture improvement, and stabilization of critically eroding areas, and cover for sandy soils with high erosion hazards and minimum levels of saline or alkaline sites. It is a host for about six species of butterflies and the Federal Highway Administration recommends it for roadside plantings.

Status

Please consult the PLANTS Web site and your State Department of Natural Resources for this plant’s current status (e.g. threatened or endangered species, state noxious status, and wetland indicator values).

Description and Adaptation

Legume Family (Fabaceae). A native, warm-season legume, either sprawling or trailing with grayish-green hairy perennial from woody taproot. Stems solitary or several, usually much branched, from 1-4 feet long. Flowers are three-quarters of an inch long with brick-red to dark rosy-red, and five petals with the upper petal erect. Flowers are 8-25 inches in terminal spike (raceme), from axils of leaves and spike longer than subtending leaf and with 7-10 blooms per spike. The leaves are alternate, short-stalked with blades divided into five to nine leaflets, and rarely each leaflet to one-inch long. With a deep root system, it is drought tolerant and normally prostrate to 50-inches long, and equipped with tendrils for climbing. The mature seed pods range from one-two inches long, with a sharp point. Pods have an average of 10 square seeds, which are 2 mm wide and 3 mm long. Seed pods are harvested with the combine and threshed with the hammer mill before cleaning. There are approximately 97,000 seeds per pound.

Adaptation: Western indigo is found in native grassland throughout much of central and east central Texas, where it is recognized as one of the valuable native legumes. It is apparently adapted to moist soil types, from sandy loam through clay loam. It will compete with other plants and has a tendency to flatten out under grazing pressure. Plants range from Kansas south to Texas, Florida, Mexico, and Cuba.

Establishment

Western indigo should be seeded as early in the spring as possible. It can be planted in range and pasture mixtures, especially where a drought tolerant legume is needed. Mechanical and acid scarification and soaking in hot water can enhance germination. Native grass drills equipped with coulters and legume box such, as Truax, Great Plains, or Tye are the best units for planting. If a drill is not available or cannot be used due to undulating terrain, broadcasting the seed and after tracking the ground with a bulldozer is also an excellent planting method.

Management

Western indigo has few management needs, except to not overgraze so that it can produce seed for new plants to grow.

Cultivars, Improved, and Selected Materials (and area of origin)

There are currently no cultivars of western indigo in the commercial production.

Prepared By and Species Coordinator:

Rudy G. Esquivel, USDA NRCS Plant Materials Center, Knox City, Texas

Edited: 23mar2006 jsp; 060801 jsp

For more information about this and other plants, please contact your local NRCS field office or Conservation District, and visit the PLANTS Web site<https://plants.usda.gov> or the Plant Materials Program Web site <https://Plant-Materials.nrcs.usda.gov>

Attribution: U.S. Department of Agriculture