Flora of the Hawaiian Islands
Monocotyledon Literature for Digitaria violascens
Wagner et al., 1990, 1999.
   Poaceae -- The Grass Family Bibliography
      Digitaria violascens

Common name(s): crabgrass, kukaepua`a uka, smooth crabgrass, violet crabgrass
General Information
DistributionNative to China, India, and Australia, now widely distributed in the Neotropics.In the Hawaiian Islands, naturalized on Kaua`i, O`ahu, Moloka`i, Lana`i, Maui, Hawai`i.

Annuals or sometimes perennials; culms erect or decumbent at base, slender, 20-60 cm tall, glabrous, leaves crowded near base.
Sheaths 1-6 cm long, compressed, keeled; ligule membranous, ca. 1 mm long; blades often red-tinged, flat, usually 2-6(-10) cm long, 3-6 mm wide, margins glabrous or scaberulous, upper surface occasionally sparsely pilose at base.
Inflorescence of 2-9 subdigitate racemes on an axis 2-5 cm long, racemes usually spreading or recurved, 3-12 cm long, slender, rachis narrowly winged, 0.5-0.7 mm wide; spikelets usually dark brown, in groups of 3, elliptic, 1.5-1.7 mm long, pedicels subterete, the longest one 1.5-2 mm long, scabrous, the others 0.7-1 mm and 0.2-0.5 mm long; first glume absent, second glume 1-1.2 mm long, 3-nerved, appressed silky pilose between the nerves, apex obtuse; first lemma 1.5-1.7 mm long, 5-nerved, obscurely appressed silky pilose between the nerves, apex obtuse; second lemma dark brown, 1.5-1.7 mm long, apex acute; palea similar to lemma.
Caryopsis whitish, 1-1.2 mm long, elliptic-ovate.
2n = 18, 36