Sporobolus silveanus

Swallen
Common names: Silveus' dropseed
Endemic
Treatment appears in FNA Volume 25. Treatment on page 137.

Plants perennial; cespitose, not rhizomatous. Culms 70-120 cm. Sheaths shiny and indurate basally, glabrous or appressed hairy elsewhere, hairs to 4 mm; ligules 0.2-0.8 mm; blades 15-52 cm long, 1-2.5 mm wide, flat, folded or involute, bluish-green, remaining so well into winter, glabrous on both surfaces, margins scabridulous. Panicles 21-50 cm long, 5-12(15) cm wide, longer than wide, open, not diffuse, pyramidal to ovate, with few spikelets; lower nodes with 1-2(3) branches; primary branches 6-20 cm, ascending, spreading 20-50° from the rachis, not capillary, without spikelets on the lower 1/4–1/2; secondary branches appressed to loosely spreading; pulvini glabrous; pedicels 3-8(14) mm, longer or shorter than the spikelets, appressed, glabrous, scabrous. Spikelets 4.5-7(7.2) mm, purplish. Glumes subequal to unequal, linear-lanceolate to lanceolate, membranous; lower glumes 3-4.6 mm, 0.6-0.9 times as long as the upper glumes; upper glumes 4-7.2 mm, from slightly shorter to longer than the spikelets; lemmas 4.4-6.5 mm, lanceolate, membranous, glabrous, acuminate to acute; paleas 4.5-6.7 mm, lanceolate, membranous, glabrous; anthers 3, 3.5-5 mm, purplish. Fruits 1.8-2.2 mm, obovoid, laterally flattened, light brownish. 2n = unknown.

Distribution

Okla., Fla., Ga., Tex., La.

Discussion

Sporobolus silveanus is restricted to the southeastern United States. It grows in wet to mesic pine woodlands and adjoining glades and barren openings, and in black-land prairies, at elevations of 5-200 m.

Selected References

None.

Lower Taxa

None.