Digitaria filiformis is an annual (probably C4, see Waller and Lewis 1979) grass, 5-90 cm tall, branched from base, stems filamentous, not rooting at nodes; lower sheaths hairy.
Leaves 5-20 cm long, 0.2-0.6 cm wide, flat, often hairy below, rough above.
Flower spikelets about 0.2 cm, 1-flowered, 2-3 together, hardly overlapping, glumes glandular-hairy, lemma dark, brown or purplish, longer than glume; inflorescence of 2-6 thin spikes 1-15 cm long along the end of the flowering stem, spike axis 3-angle, hardly winged; blooms and fruits Aug.-Oct.
Wetland status: NL.
Frequency in NYC: Very infrequent.
Habitat: Open, sandy sterile soil.