Difference between revisions of "Danthonia intermedia"

Revision as of 21:34, 16 December 2019

Illustrator: Linda A. Vorobik, Hana Pazdírková

Culms 10-50(70) cm, not disarticulating at maturity. Sheaths usually glabrous; blades 5-10 cm long, 1-3.5 mm wide, glabrous or slightly pilose. Inflorescences with (4)5-10 spikelets; branches stiff, appressed or strongly ascending; lower branches with (1)2-3(5) spikelets; pedicels on the lowest branch shorter than the spikelets. Spikelets 11-15(19) mm. Calluses of middle florets longer than wide, concave abaxially; lemma bodies 3-6 mm, glabrous over the back, densely pilose along the margins, teeth 1.5-2.5 mm, acute to acuminate or aristate; awns 6.5-8 mm; anthers usually tiny, sometimes to 4 mm. Caryopses (2)2.3-3 mm long, 0.7-1.1 mm wide. Cleistogenes rarely produced. 2n = 36, 98.

Colo., N.Mex., Wash., Utah, Alaska, Alta., B.C., Man., Nfld. And Labr., Ont., Que., Sask., Yukon, Mich., Idaho, Mont., S.Dak., Wyo., Ariz., Calif., Nev., Oreg.

Discussion

Danthonia intermedia grows in boreal and alpine meadows, open woods, and on rocky slopes and northern plains. Its range extends from Kamchatka, Russia, to North America, south along the cordillera, and east, through boreal and alpine regions, to Quebec and Newfoundland and Labrador. Its primarily cleistogamous reproduction has probably facilitated its establishment and spread through more boreal and alpine habitats than other members of the genus.

Tzvelev (1976) treats the American plants as D. intermedia (Vasey) subsp. intermedia and the Russian plants, which have 2n = 18, as D. intermedia subsp. riabuschinskii (Kom.) Tzvelev.

Selected References

None.

Lower Taxa