Plants cespitose. Basal rosettes well-differentiated;
blades 2-6 cm long, about 1 cm wide, ovate, the uppermost leaves often
resembling the lower cauline blades. Culms 15-50 cm, few together, decumbent
or ascending, light green, glabrous, slightly fleshy or thickened; fall phase branching
mostly near the bases, with sparse branching; nodes appressed-pubescent
or glabrous. Cauline leaves 3-4(6); sheaths sometimes overlapping
near the bases, glabrous, margins ciliate; ligules almost obsolete, or
of 0.2-0.8 mm hairs from a tiny membranous base; blades 1.5-10 cm long,
5-14 mm wide, thick, light green, faintly veined, bases cordate, with papillose-based
cilia, margins white, cartilaginous. Primary panicles 4-14 cm, more than
1/2 as wide as long, usually long-exserted. Spikelets 1.4-1.8 mm, broadly
obovoid-spherical, usually puberulent, sometimes glabrous. Lower glumes
0.4-0.8 mm, acute to obtuse, upper florets 1.1-1.5 mm, broadly ellipsoid,
blunt. 2n = 18.
Dichanthelium sphaerocarpon grows in dry, open woods and roadsides. Its
range extends from eastern North America to Ecuador and Venezuela. It occasionally
hybridizes with several other species, including D.
polyanthes, D. acuminatum, and D. laxiflorum.
Perennial herb, tufted 15 cm - 0.5 m tall Inflorescence: a terminal, branched arrangement of spikelets (panicle). Primary panicles atop the culms, 4 - 14 cm long, more than half as wide as long, long-exserted. Secondary panicles (when present) atop the branches. Fruit: a caryopsis, indehiscent, enclosed within the persistent lemma and palea. Culm: ascending or decumbent, 15 cm - 0.5 m long, round in cross-section, hollow, slightly fleshy or thickened. Nodes sometimes appressed-hairy. Fall phase sparsely branching, mostly from near the bases. Spikelets: about 1.5 mm long, broadly reverse egg-shaped to spherical, often minutely hairy. Basal leaves: in a rosette. Blades 2 - 6 cm long, about 1 cm wide, egg-shaped, uppermost leaves often similar to lower stem blades. Stem leaves: three to six, alternate, two-ranked. Sheaths sometimes overlapping basally, usually shorter than internodes, fringed with hairs. Ligules nearly obsolete, or composed of very short hairs from a membranous base. Blades thick, whitish along the margins, distinctly longer and narrower than basal leaves, 1.5 - 10 cm long, 0.5 - 1.5 cm wide, lance-shaped with a heart-shaped base, faintly veined, fringed with bumpy-based hairs basally. Glumes:: Lower glumes about 0.5 mm long, blunt to pointed at the apex. Upper glumes rounded to pointed at the apex. Lemmas:: Lower lemmas similar to upper glumes. Upper lemmas longitudinally lined, shiny, with rolled-up margins above. Paleas:: Lower paleas shorter than lower lemmas, thin. Upper paleas longitudinally lined. Florets:: Upper florets bisexual, stalkless, 1 - 1.5 mm long, broadly ellipsoid with a blunt apex, plump. Anthers three. Stigmas red.
Similar species: No information at this time.
Flowering: June to mid-July
Habitat and ecology: Locally frequent in dry sandy soil in the dune area of Lake Michigan.
Occurence in the Chicago region: native
Etymology: Dichanthelium comes from the Greek words di, meaning twice, and anth, meaning flowering, referring to plants that may have two flowering periods. Sphaerocarpon means spherical-fruited.
Culms few-several, spreading, 1.5-5 dm, glabrous except the appressed-hairy nodes; sheaths glabrous (and sometimes viscous-spotted) on the back, villous-ciliate with hairs usually 1-2 mm, some of the sheaths shorter than the internodes; ligule typically none, but sometimes a band of hairs to 1 mm; blades cordate and papillose-ciliate at base, the largest ones 6-12 cm נ7-15 mm, the primary veins scarcely stronger than the sets of 3-5 intermediate veins; flag-lf mostly 3-9 cm, typically borne ±midway between the stem-base and the panicle-tip; primary panicle 5-10 נ4-8 cm, long-exsert at anthesis, with spreading branches; spikelets (excluding the first glume) almost spherical, minutely puberulent, 1.3-1.9 mm, the first glume a third as long, broadly ovate; autumnal phase more widely spreading or prostrate, the few branches mostly from the base and lower nodes, the lvs and panicles scarcely reduced; 2n=18. Moist or dry, preferable shady places; Mass. and Vt. to O. and Kans., s. to Fla. and Tex. (Dichanthelium s.)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.