Digitaria sanguinalis

hairy crabgrass, purple crabgrass, hairy crab grass, large crabgrass, crabgrass, redhair crabgrass, northern crabgrass


Leaf Arrangement


Leaf Type


Leaf Shape


Growth Form


Flower Color


Flower Month

July - December

Height (meters)

0.2 - 1.1

Milky Sap








Growing Season

Warm season

Wetland Class


Prairie Coefficient of Conservatism


Field Characters

The most common of the southern crabgrasses. It is easily mistaken for D. ciliais which is also widespread but has hairless to sparsely papilose-pilose foliage and hairless nerves on the sterile lemma, while the foliage of D. sanguinalis is densely hairy, and has short, transparent spines on the nerves of the sterile lemma.

Cultural Information

Produces a heavy seed crop 15-24 inches from the ground. This species germinates best with alternating temperature of 68-86 F (20-30) C. Moist prechilling at 35-40 F (2-5 C) for 2-4 weeks, and acid scarification with concentrated sulfuric acid for 1/2-3 minutes both speeded germination. Seed germination improves over time as seeds after-ripen during dry storage. Light appears to increase germination (Toole and Toole 1941). Seed dormancy can also be broken by scarification and soaking (Gianfagna and Pridham 1952). There are 825,000 seed/lbs.

Animal Use

This information is for the genus Digitaria with note that D. ischaemum, D. anguinalis, and D. filiformis are especially valuable to wildlife. This species spring growth is preferred by cattle. Animals that eat its seeds: Ground dove, Mourning dove, Bobwhite quail, Wild turkey, Cowbird, Slate-colored junco, American pipit, Chipping, field, savannah and tree sparrows, Clay-colored and english sparrow, Pine-woods, song, swamp and white-crowned sparrows. Animals that eat the plants: Cottontail rabbit (Martin et al. 1951).

Natural History

A warm-season, shallow-rooted annual that reproduces by seed and by rooting where nodes touch the soil. Bunches of this grass are somewhat flattened with many branches that grow and root along the ground, eventually turning upward. This growth habit protects the plant from grazing and mowing. Infrequent cultivation actually spreads the vegetative, rooted nodes. This species grows on a wide variety of soils throughout the United States at low altitudes. It has become a lawn and garden weed in the East and South. It invades overgrazed and disturbed range but is palatable to livestock and if moisture is right can be productive. Geese have been used to graze crabgrass out of cultivated crops. The genus name Digitaria refers to the Latin word "digitus" or finger-like and describes the type of seed head common to this group. It is a northern European species now widespread in temperate areas. It usually grows in disturbed soil along roads, in fields, ditches and gardens and occurs in north-central and eastern Texas and rarely in the northern part of Louisiana.


Fields, roadsides, and waste places.