Dichanthelium acuminatum subsp. columbianum
Plants cespitose, pale bluish- or grayish-green. Culms erect to ascending, densely puberulent, longer hairs often present also, at least on the lower portion of the culms; nodes puberulent; fall phase with spreading or decumbent culms, branching early from most nodes, secondary blades not as greatly reduced or as densely crowded as in subspp. acuminatum, fasciculatum, implicatum, and leucothrix. Cauline sheaths pubescent, their pubescence similar to that of the culms but some¬what less dense; midculm sheaths about 1/2 as long as the internodes; ligules 1-1.5 mm; blades 3-7 cm long, 3-7 mm wide, relatively firm, often ascending, abaxial sur¬faces densely puberulent to nearly glabrous, adaxial sur¬faces glabrous or sparsely pilose near the base, margins whitish-scabridulous. Spikelets 1.5-1.9 mm, broadly ellipsoid or obovoid, puberulent.
Discussion
Dichanthelium acuminatum subsp. columbianum grows in sandy woods or clearings in the northeastern portion of the species range. It is much less common than the other eastern subspecies of D. acuminatum. Occasionally, it resembles the more widespread subsp. fasciculatum, subsp. implicatum, and subsp. lindheimeri.
The culms and sheaths of Dichanthelium acuminatum subsp. columbianum are always puberulent with very short hairs. This puberulence should not be confused with the slightly longer hairs that develop on the secondary branches of other taxa.
Selected References
None.