Dichanthelium strigosum
Dichanthelium oligosanthes
cushion-tuft panicgrass, roughhair rosette grass
few-flower panic grass, few-flower rosette-panicgrass, few-flower witchgrass, fewanther obscuregrass, Heller's rosette grass, Scribner's panic grass, Scribner's perennial panicgrass, Scribner's witchgrass
5-45 cm, slender, erect or spreading;
from a dense tuft of predominantly basal leaves, lower internodes short, upper 3-5 internodes elongate;
nodes glabrous or bearded;
internodes glabrous or pilose;
fall phase with spreading culms and branches arising from near the bases forming a dense, flat tuft.
20-75 cm, geniculate basally, stiffly erect distally;
nodes glabrous or sparsely pubescent;
internodes often purplish, glabrous, puberulent, or papillose-hirsute;
fall phase branching from the midculm nodes, branches initially ascending to erect, sometimes developing simultaneously with and overtopping the primary panicles, later rebranching to form short, bushy clumps of blades and small, included secondary panicles.
2-4;
lower cauline sheaths longer than the internodes, mostly glabrous or pilose with ascending hairs, margins finely ciliate;
ligules 0.2-2 mm, at low magnification appearing to be membranous and ciliate, at high magnification evidently of hairs that are coherent at the base;
blades 1.5-6 cm long, 3-8 mm wide, lanceolate, glabrous or softly pilose, margins with prominent papillose-based cilia, at least basally.
5-7;
sheaths not overlapping, glabrous, puberulent, or ascending papillose-hispid, margins ciliate, collars loose, puberulent;
ligules 1-3 mm, of hairs;
blades 5-12 cm long, 4-15 mm wide, flat or partly involute, glabrous or pubescent abaxially, with 7-9 major veins only slightly more prominent than the minor veins, bases ciliate, rounded to truncate, margins cartilaginous.
1.1-2.1 mm, obovoid to broadly ellipsoid, glabrous or pubescent, hairs not papillose-based.
2.7-4.2 mm long, 1.7-2.4 mm wide, ellipsoid to broadly obovoid, turgid, glabrous or sparsely pubescent.
1/3 - 1/2 as long as the spikelets, acute to obtuse;
upper florets 0.8-1.7 mm, ellipsoid, subacute.
1-1.6 mm, acute, similar in texture and vein prominence to the upper glumes;
upper glumes strongly veined, often orange to purplish at the base;
lower florets sterile;
upper florets with minutely umbonate apices.
rosettes poorly differentiated;
blades 1-5 cm, lanceolate, grading into the cauline blades.
rosettes well-differentiated;
blades 2-6 cm, few, ovate to lanceolate.
panicles short- to long-exserted;
rachises and branches often pilose.
panicles 5-9 cm long, 3-6 cm wide, partly enclosed to long-exserted, with 6-60 spikelets;
branches stiff or wiry, puberulent or scabridulous.
= 18.
Dichanthelium strigosum
Dichanthelium oligosanthes
Dichanthelium strigosum extends from the southeastern Flora region south into Mexico, the Caribbean, and into northern South America.
The primary panicles are briefly open-pollinated in April or May; the secondary panicles, which are produced from May through November, are cleistogamous. The three subspecies are mostly sympatric and sometimes grow together, with occasional intergradation.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Dichanthelium oligosanthes grows throughout the southern portion of the Flora region and extends into northern Mexico. The primary panicles are briefly open-pollinated, then cleistogamous, from late May to early June; the secondary panicles, which are produced from June to November, are cleistogamous. The subspecies intergrade in areas of overlapping range, but they are usually distinct elsewhere.
Specimens of Dichanthelium oligosanthes that have few elongated internodes, but those elongated more than usual, are often mistaken for D. wilcoxianum. Unlike that species, however, they have turgid spikelets with an orange spot at the base of the lemma, indicating that they belong to D. oligosanthes. Such specimens seem to be most common among collections made in the southern and southwestern states during November, February, or March.
Sterile hybrids with Dichanthelium acuminatum have often been called Panicum scoparioid.es Ashe. Apparent hybrids with D. malacophyllum, D. ovale, and D. acuminatum subsp. columbianum are occasionally found.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Spikelets pubescent, broadly ellipsoid, 1.6-2.1 mm long; lower glumes about 1/2 as long as the spikelets; blades glabrous | subsp. leucoblepharis |
1. Spikelets glabrous, obovoid, 1.1-1.8 mm long; lower glumes about 1/3 as long as the spikelets; blades pilose or glabrous. | → 2 |
2. Blades pilose; spikelets 1.1-1.6 mm long | subsp. strigosum |
2. Blades glabrous or sparsely pilose near the base; spikelets 1.4-1.8 mm long | subsp. glabrescens |
1. Spikelets ellipsoid to oblong-obovoid, usually 3.4-4.2 mm long, 1.7-2 mm wide, usually sparsely pubescent; blades usually 4-9 mm wide, more than 10 times longer than wide, often partly imolute; ligules 2-3 mm | subsp. oligosanthes |
1. Spikelets broadly obovoid-ellipsoid, 2.7-3.5 mm long, 2-2.4 mm wide, usually glabrous; blades usually 6-15 mm wide, less than 10 times longer than wide, flat; ligules 1-1.5 mm long | subsp. scribnerianum |
- Local floras:
BC, 
OR, 
WA - Local Web sites:
CalFlora, CalPhotos, 
Flora NW, 
Go Botany, 
IL Wildflowers, 
KS Wildflowers, 
LA Plants, 
MD Biodiversity, 
MI Flora, 
MN Wildflowers, 
MO Plants, 
PNW Herbaria 
WildflowerSearch
iNaturalist (observations)
USDA Plants Database- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
