Danthonia unispicata

(Thurb.) Munro ex Vasey
Common names: One-spike oatgrass
Endemic
Treatment appears in FNA Volume 25. Treatment on page 305.

Culms (10) 15-30 (42) cm, disarticulating at the nodes at maturity. Sheaths usually densely pilose, hairs sometimes papillose-based (upper sheaths sometimes glabrous); blades 3-8 (20) cm long, 1-3 mm wide, both surfaces sparsely to densely pilose, sometimes also scabrous or hirsute (rarely glabrous). Inflorescences with 1-2 (3) spikelets, if more than 1, racemose; pedicels stiff, appressed, shorter than the spikelets. Spikelets (8) 12-26 mm. Calluses of middle florets longer than wide, concave abaxially; lemma bodies 5.5-11 mm, glabrous over the back (rarely with a few scattered hairs), margins pilose (rarely glabrous), apical teeth 1.5-7 mm, acute to aristate; awns 5.5-13 mm; anthers to 3.5 mm. Caryopses 2.2-4 mm long, about 1 mm wide. 2n = 36.

Distribution

Colo., Wash., Utah, Calif., Oreg., Alta., B.C., Sask., Mont., Wyo., Idaho, Nev., S.Dak.

Discussion

Danthonia unispicata is restricted to western North America, where it grows in prairies and meadows, on rocky slopes, and in dry openings up to timberline in the mountains. It differs from D. californica in its shorter stature, usually densely pilose foliage, short, erect pedicels, and the usually erect cauline leaf blades. It is closely related to D. californica, and some authors prefer to treat it as D. californica var. unispicata Thurb.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number."elongated" is not a number.

... more about "Danthonia unispicata"
0 cm0 mm <br />0 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
Obtuse (?) +, Awned (?) +  and Mucronate (?) +
acute +  and aristate +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
Stephen J. Darbyshire +
(Thurb.) Munro ex Vasey +
1 (?) +  and 3 (?) +
geniculate +
0.55 cm5.5 mm <br />0.0055 m <br /> (1.3 cm13 mm <br />0.013 m <br />) +
pilose +  and glabrous +
keeled +  and rounded +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
not pseudopetiolate +
3 cm30 mm <br />0.03 m <br /> (8 cm80 mm <br />0.08 m <br />) +
involute +, flat +  and rolled +
1mm;3mm +
hirsute +  and scabrous +
spikelike +
longer than wide +
0.22 cm2.2 mm <br />0.0022 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
flattened +, ovate +  and obovate +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.55 cm5.5 mm <br />0.0055 m <br />) +
1 cm10 mm <br />0.01 m <br /> (?) +
not disarticulating +
One-spike oatgrass +
disarticulating +
perennial +  and annual +
15 cm150 mm <br />0.15 m <br /> (30 cm300 mm <br />0.3 m <br />) +
woody +  and herbaceous +
Colo. +, Wash. +, Utah +, Calif. +, Oreg. +, Alta. +, B.C. +, Sask. +, Mont. +, Wyo. +, Idaho +, Nev. +  and S.Dak. +
small +  and large +
capillary +
sometimes longer +
1 +, 3 +  and 12 +
compressed +
cleistogamous +  and chasmogamous +
(1)3-7-veined +
subtending +
subequal +
papillose-based +
non-uncinate +
1/3 +  and 3/4 +
spicate +  and ebracteate +
solid +  and hollow +
scabrous +  and glabrous +
0.55 cm5.5 mm <br />0.0055 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
scabrous +  and glabrous +
rounded +
coriaceous +
acute +  and aristate +
inconspicuous +
with a few hairs +  and glabrous +
extended +
concealed +  and prominent +
2 +  and 1 +
well-developed +
sometimes slightly longer +
hirsute +  and scabrous +
dry +  and fleshy +
0 cm0 mm <br />0 m <br /> (12 cm120 mm <br />0.12 m <br />) +
hirsute +  and scabrous +
sterile +, bisexual +  and unisexual +
compressed +  and terete +
1.2 cm12 mm <br />0.012 m <br /> (2.6 cm26 mm <br />0.026 m <br />) +
1 (?) +  and 3 (?) +
2 (?) +  and 3 (?) +
hirsute +, scabrous +  and pilose +
Gramineae +
Danthonia unispicata +
Danthonia +
species +
membranous +
plant +  and cespitose +
aquatic +  and terrestrial +