Differentiating features of Stipa-species with plumose awns in Mongolia

Table of used features in Stipa-species with plumose awns (hairs longer than 0.8 mm)

feature leaf blades outside ligule of vegetative shoots (mm) glumes (mm) lemma (mm) awn (cm) awn geniculate* awn hairs above bend
S. breviflora smooth 0.2-0.4, very short Grubov 1982: 8-12, Flora of China: 12-20 (5)6-8, apex spinulose 5.5-6.2 pilose throughout length (once or*) twice 1-1.5 mm
S. orientalis strongly scabrous 1-3 15-25 5-8 5-7 pilose throughout length twice 2.5-4( 5), shorten in length toward apex
S. glareosa scabrous (sometimes also glabrous) up to 0.5, densely pilose (19)20-35 7.5-8(9) 4.5-7 pilose throughout length once 3-5 mm, shorten in length toward apex
S. caucasica usually smooth up to 5 35-40 9-12 7-14 pilose throughout length once 3-5 mm, shorten in length toward apex
S. mongolorum smooth or almost so up to 6 14-19 6-7.5 4.5-6.5 pilose throughout length once 2-3.5 mm, shorten in length toward apex
S. gobica scabrous 0.2-0.6, long pilose 18-27 7-9 6-8 awn below bend glabrous once -3 mm (rarely up to 5)
S. klemenzii glabrous 0.2-0.6, long pilose 25-35 (40) 9-11 (7.5)9.5-13 awn below bend glabrous once -6.5 mm
S. rubens scabrous 0.5-3, glabrous no declaration 16-19 25-40 awn below bend glabrous twice
S. kirghisorum 0.5-3, glabrous 20-25 awn below bend glabrous twice
S. pennata 0.5-3, glabrous 20-40 awn below bend glabrous twice

* awn once or twice geniculate is sometimes not an accurate or properly applied attribute because it is often difficult to recognize

data compiled by: S. Rilke