Digitaria flaccida Stapf

Gramineae, W. D. Clayton, S. M. Phillips & S. A. Renvoize. Flora of Tropical East Africa. 1974

Morphology General Habit

Densely tufted perennial, the base fibrous and tomentose; culms 30–100 cm. high, erect.

Morphology Leaves

Leaf-blades narrow, 5–30 cm. long, 1–3 mm. wide.

Morphology Reproductive morphology Inflorescences

Inflorescence loose or contracted, of 5–30 delicate racemes arranged on a central axis 10–30 cm. long, not whorled; racemes up to 5–10 cm. long, with a flexuous filiform rhachis naked for the lower 1/3–1/2 its length and bearing paired spikelets above (sometimes the larger branches bearing short secondary racemes); pedicels pubescent at the tip.

Morphology Reproductive morphology Inflorescences Spikelets

Spikelets narrowly elliptic, 2.5–4 mm. long; lower glume absent, or just discernible as a tiny hyaline rim; upper glume 1/2–2/3 as long as the spikelet, 3-nerved, bulging slightly downwards beside the pedicel-tip, appressed pubescent between the nerves or silky pilose all over, long ciliate on the margins with stiff silky purplish hairs; lower lemma as long as the spikelet, 5-nerved, with stiff silky purplish hairs on and between 1st and 2nd lateral nerves (often glabrous near the base), these becoming longer upwards and typically forming a long tuft at about the middle of the lemma, thereafter the nerves glabrous or pubescent but the margins becoming ciliate; fruit ellipsoid, pallid.

Habitat

Brachystegia wooded grassland; 900–1050 m.

Distribution

T7 T8 Zaire to South Africa

Morphology General Habit

Perennial; caespitose. Butt sheaths glabrous, or pubescent; persistent and investing base of culm; with fibrous dead sheaths. Culms erect; 30-100 cm long. Ligule an eciliate membrane. Leaf-blades 5-30 cm long; 1-3 mm wide.

Morphology Reproductive morphology Inflorescences

Inflorescence composed of racemes. Racemes 5-30; borne along a central axis; simply spaced, or closely spaced; flexuous; unilateral; 5-10 cm long. Central inflorescence axis 10-30 cm long. Rhachis wingless; angular. Raceme-bases filiform; 20-50 mm long. Spikelets in pairs. Fertile spikelets pedicelled; 2 in the cluster. Pedicels unequal; pubescent; hairy at tip.

Morphology Reproductive morphology Inflorescences Spikelets

Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; 2.5-4 mm long; falling entire.

Fertile

Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; 2.5-4 mm long; falling entire.

Morphology Reproductive morphology Inflorescences Bracts Glume

Glumes one the lower absent or obscure; shorter than spikelet; thinner than fertile lemma. Upper glume elliptic; gibbous; 0.5-0.66 length of spikelet; membranous; without keels; 3 -veined. Upper glume surface pubescent, or pilose; hairy generally, or between veins. Upper glume margins ciliate. Upper glume apex acute.

Morphology Reproductive morphology Flowers Florets

Basal sterile florets barren; without significant palea. Lemma of lower sterile floret elliptic; 1 length of spikelet; membranous; 5 -veined; pilose; hairy below; hairy between veins (1st and 2nd laterals); with dorsal tufts of hair; 2 hair tufts in all; ciliate on margins (above); bearing purple hairs; acute. Fertile lemma elliptic; 2.5-4 mm long; cartilaginous; much thinner on margins; pallid; without keel. Lemma margins flat; covering most of palea. Lemma apex acute. Palea cartilaginous.

Distribution

Africa: west-central tropical, east tropical, southern tropical, and south.

Reference

Paniceae. FTEA.

Gramineae, W. D. Clayton. Flora Zambesiaca 10:3. 1989

Morphology General Habit

A tightly caespitose perennial, bulbously thickened base surrounded by woolly cataphylls and old leaf sheath remnants.

Morphology Culms

Culms 40–70 cm., erect, glabrous, nodes dark, glabrous.

Morphology Leaves Leaf sheaths

Leaf sheaths glabrous.

Morphology Leaves Ligules

Ligule c. 0.5 mm. long, truncate, shortly ciliate.

Morphology Leaves Leaf lamina

Leaf laminae 5–10 × 0.3–0.4 cm., linear, flat, scaberulous on the superior surface, glabrous on the inferior surface, scaberulous on the margin.

Morphology Reproductive morphology Inflorescences

Inflorescence composed of (6)10–17 racemes, 2–7 cm. long (incl. pedicel), few-flowered, long pedicelled, sometimes branched, a few together or all solitary along a long, well developed common axis.

Morphology Leaves Rachis

Rhachis triquetrous, scarcely winged, up to 0.4 mm. broad, smooth with smooth to scabrous margins.

Morphology Reproductive morphology Flowers Pedicel

Pedicels 2-nate, 1–3 mm. long, triangular to compressed, basally smooth, asymmetrically broadened at the apex, bearing a setulose coronula.

Morphology Reproductive morphology Inflorescences Spikelets

Spikelets (2.5)2.8–3.2(4.1) mm. long, oblong.

Morphology Reproductive morphology Inflorescences Bracts Glume

Inferior glume absent or obsolete. Superior glume c. | of the spikelet, oblong-triangular, 3-nerved, the central nerve poorly developed, basally conspicuously spurred, appressed hairy, hairs white to purple, stiff, acute.

Inferior

Inferior glume absent or obsolete. Inferior lemma as long as the spikelet, oblong with recurved margins, 5-nerved, appressed hairy, densely on the inferior half, in 4 rows on the superior half.

Morphology Reproductive morphology Inflorescences Bracts Lemma

Superior lemma as long as the spikelet, oblong, acuminate, basally spurred, but not gibbous, pale yellowish green. Inferior lemma as long as the spikelet, oblong with recurved margins, 5-nerved, appressed hairy, densely on the inferior half, in 4 rows on the superior half.

Superior

Superior lemma as long as the spikelet, oblong, acuminate, basally spurred, but not gibbous, pale yellowish green. Superior glume c. | of the spikelet, oblong-triangular, 3-nerved, the central nerve poorly developed, basally conspicuously spurred, appressed hairy, hairs white to purple, stiff, acute.