Paspalum setaceum var. villosissimum (Nash) D. J. Banks (redirected from: Paspalum villosissimum)
Family: Poaceae
[Paspalum villosissimum ]
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Plants erect. Leaves conspicuously basal; blades to 15 cm long, 3-10 mm wide, recurved, hirsute, usually with long stiff hairs and short soft hairs, grayish-green, margins ciliate, with long stiff hairs. Panicle branches 2-11.2 cm; branch axes 0.3-0.9 mm wide. Spikelets 1.4-1.9 mm long, 1.1-1.6 mm wide, elliptic, obovate, orbicular, or suborbicular, short pubescent to nearly glabrous, often purple-spotted; lower lemmas without an evident midvein; upper lemmas 1.3-2 mm.

Paspalum setaceum var. villosissimum grows in sandy fields and flatwoods of Florida and Cuba. It resembles var. longepedunculatum, differing in its pubescent leaves, more robust habit, and more developed rhizomes.

Perennial herb with short rhizomes or forming tufts 25 cm - 1 m tall

Leaves: basal. Sheaths open, sometimes hairy. Ligules to 0.5 mm long, membranous. Blades recurved, to 15 cm long, 3 - 10 mm wide, lance-shaped, flat, parallel-veined, hairy, usually covered with short soft hairs and long stiff hairs, fringed with long stiff hairs.

Inflorescence: a branched arrangement of spikelets (panicle), terminal and axillary, bearing one to six spike-like branches. Axillary panicles completely or partially enclosed by a subtending leaf sheath. Branches ascending to spreading, often bowed, 2 - 11 cm long, with spikelets mostly arranged in two rows along one side of the branch. Branch axes 0.3 - 0.9 mm wide, sometimes rough.

Fruit: a caryopsis, indehiscent, enclosed within the persistent lemma and palea, white, elliptic to nearly orbicular.

Culm: upright, 25 cm - 1 m long, round in cross-section, hollow. Nodes sometimes hairy.

Spikelets: paired, overlapping, arranged along one side of the inflorescence branch, appressed to the branch axis, bearing two florets, straw-colored or brown, 1.5 - 2 mm long, 1 - 1.5 mm wide, plano-convex (one side flat, the other convex), nearly orbicular to orbicular to reverse egg-shaped to elliptic, nearly hairless to shortly hairy, often with purple spots.

Glumes:: Lower glumes absent. Upper glumes nearly equal to lower lemmas, rounded at the apex, three-veined, sometimes shortly glandular-hairy, membranous.

Lemmas:: Lower lemmas nearly equal to upper glumes, rounded at the apex, three-veined, sometimes shortly glandular-hairy, membranous. Upper lemmas clasping the paleas, straw-colored to brown, convex, smooth to slightly wrinkled, with rolled-up margins on the upper surface.

Paleas:: Lower paleas rudimentary or absent. Upper paleas straw-colored to brown, smooth to slightly wrinkled.

Florets:: Lower florets sterile. Upper florets bisexual, straw-colored, 1.5 - 2 mm long. Anthers three. Stigmas red.

Similar species: No information at this time.

Flowering: June to September

Habitat and ecology: Sandy areas.

Occurence in the Chicago region: native

Etymology: Paspalum comes from the Greek word paspalos, a type of millet. Setaceum means bristle-like. Villosissimum means "very long-hairy."

Author: The Morton Arboretum

From Flora of Indiana (1940) by Charles C. Deam

This species is found sparingly in the northern two thirds of the state and is infrequent to frequent in the southern part. It prefers moist, sandy soil but adapts itself to many habitats. It is usually found in pastured fields and woodlots.