Piptatherum canadense
Piptatherum racemosum
Canada mountain-rice grass, Canadian piptatherum, Canadian ricegrass, oryzopsis du Canada
black-seed mountain-rice grass, mountain ricegrass
30-90 cm, glabrous;
basal branching mostly intravaginal.
48-80 cm, scabrous or pubescent adjacent to the nodes;
basal branching extravaginal.
basally concentrated;
sheaths smooth or scabridulous;
ligules 1-4 mm, hyaline, truncate, rounded, or acute;
basal blades 4-15 cm long, 1-1.5 mm wide when flat, 0.5-0.8 mm in diameter when folded or convolute.
not basally concentrated;
sheaths usually smooth and glabrous, occasionally scabridulous and inconspicuously pubescent near the margins;
ligules of upper leaves 0.3-0.7 mm, truncate;
blades of basal leaves 0-2 cm;
blades of upper leaves 10-27 cm long, 8-16 mm wide, abaxial surfaces evenly but sparsely pubescent, adaxial surfaces with straight hairs to 0.3 mm on the primary veins and flexuous hairs of 0.5-0.9 mm on the minor veins, tapering from near midlength to the apices.
9-15 cm, lower nodes with 1-2 branches;
branches 1-6 cm, somewhat flexuous, ascending to divergent.
12-25 cm, lower nodes with 1-2 branches;
branches 3-9.5 cm, straight, strongly ascending to strongly divergent, with 2-5 spikelets.
subequal, 3-6 mm long, 1.3-2 mm wide, ovate, 1-3-veined, apices acute to mucronate;
florets 2.2-4.5 mm, obovoid, dorsally compressed;
calluses 0.2-0.5 mm, hairy, disarticulation scars elliptic;
lemmas coriaceous, evenly pubescent, tan at maturity, margins widely separated even when immature;
awns 5-15 mm, persistent, once- or twice-geniculate, first segments strongly twisted;
paleas similar to the lemmas in length, texture, and pubescence;
anthers 1-2 mm;
ovaries developing 2 conelike style bases, each bearing a single, unbranched style.
6-8 mm, from subequal to the florets to exceeding the florets by 2 mm, ovate, 5-7-veined, acuminate;
florets 4.5-7.5 mm;
calluses 0.3-0.6 mm, disarticulation scars circular;
lemmas coriaceous, sparsely pubescent to glabrate throughout, margins fused at the base, not overlapping, shiny dark brown to black at maturity;
awns 10-25 mm, deciduous, slightly twisted, flexuous;
anthers 3.5-5.5 mm, not penicillate;
ovaries developing 2 conelike extensions, each terminating in a style.
about 2.5 mm long, 0.5 mm thick;
hila linear, almost equaling the caryopses.
5-6 mm;
hila linear, 4/5 – 9/10 as long as the caryopses.
= 22.
= 46,48.
Piptatherum canadense
Piptatherum racemosum
Piptatherum canadense grows in grasslands and open woods, from the British Columbia-Alberta border east to Newfoundland, extending south into the Great Lakes region and the northeastern United States. Its persistent, longer awns distinguish P. canadense from P. pungens.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Piptatherum racemosum usually grows in deciduous woods, and less often in open pine woods, in rocky, mountainous areas, from the St. Lawrence and Ottawa rivers south to the Missouri River, Tennessee, and Virginia, and east to Maine. The absence of basal blades and the dark, shiny lemmas distinguish it from all other North American Stipeae. It is highly palatable to livestock, but is never sufficiently abundant to be important as forage.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
WildflowerSearch
iNaturalist
USDA Plants Database
