Plants cespitose. Basal rosettes well-differentiated;
blades 1-8 cm, lanceolate, often conspicuously ciliate. Culms
15-60 cm, usually more than 1 mm thick, not delicate, mostly ascending or spreading,
often decumbent; nodes densely to sparsely bearded with spreading, retrorse,
or appressed hairs; internodes, particularly the lower internodes, usually
long-hairy with appressed or ascending hairs, occasionally with spreading hairs,
occasionally with shorter hairs, rarely nearly glabrous; fall phase with
decumbent to prostrate culms, branching developing early and forming dense fascicles
with erect, slightly reduced blades and greatly reduced secondary panicles.
Cauline leaves 4-7; sheaths shorter than the internodes, pilose,
hairs to 4 mm, occasionally with shorter, spreading hairs underneath; ligules
and pseudoligules 1-5 mm, of hairs; blades 4-10 cm long, 3-10
mm wide, relatively firm, mostly ascending or spreading, 1 or both surfaces
sparsely to densely pubescent with appressed or erect hairs, hairs to 5 mm,
bases rounded or slightly narrowed, margins often whitish, ciliate basally,
scabridulous elsewhere. Primary panicles 3-10 cm long, nearly as wide
when fully expanded; rachises and branches often stiffly ascending
or spreading, usually pilose basally. Spikelets 1.8-3 mm, ellipsoid or
obovoid, densely to sparsely pilose or papillose-pilose, obtuse or slightly
acute. Lower glumes 1/3-1/2 as long as the spikelets, often triangular,
not strongly veined, usually acute or subacute; upper glumes usually slightly
shorter than the lower lemmas and upper florets at maturity, not strongly veined;
lower florets sterile; upper florets 1.6-2.5 mm, ellipsoid (slightly
less than 1/2 as wide as long, or wider in subsp. praecocius), subacute.
2n = 18.
Dichanthelium ovale grows in dry, open, sandy or rocky woodland borders,
sand barrens, dunes, and dry prairies in southeastern Canada, the eastern United
States, the West Indies, Mexico, and Central America. The four subspecies often
intergrade, especially subsp. villosissimum and subsp. pseudopubescens in the southeastern
United States, and subsp. villosissimum and subsp. praecocius in the
western part of their range.
The growth form and certain morphological features of Dichanthelium
ovale resemble those of the widespread D.
laxiflorum, which usually grows in more mesic habitats. Occasional specimens
exhibit traits of D. acuminatum,
D. oligosanthes, and D.
commutatum.
Culms clustered, stiff, erect or ascending, 1-6 dm, usually at least some of the sheaths and internodes with distinctly bistratal pubescence consisting of intermingled short, soft, crisp hairs and much longer (1-2+ mm) coarser hairs; sheaths conspicuously striate; ligule a dense band of short (ca 1 mm or less) hairs in front of a thin line of longer (even to 5 mm) hairs; blades ascending, 4-9 cm נ3-7 mm, involute at the tip, glabrous or with a few scattered long hairs above, glabrous to more often hairy (with unequal hairs) beneath; primary panicle ovoid, 3-8 cm; spikelets finely hairy, ellipsoid, 1.7-2.6 mm; autumnal phase becoming widely spreading to prostrate, branched chiefly from the middle nodes, the blades scarcely reduced, the panicles much reduced and surpassed by the lvs; 2n=18. Sandy soil. Var. commonsianum, of the coastal plain from Mass. to Fla., is rather thinly hairy. (P. addisonii; P. mundum) The more copiously hairy var. euchlamydeum (Shinners) Pohl is more inland, occurring from nw. Pa. to n. Ill., Wis., and e. Minn. P. commonsianum might perhaps properly be subordinated to P. ovale Elliott, of the southern coastal plain, but the proper nomenclatural innovations have not been made.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.