×achnella

Barkworth
Treatment appears in FNA Volume 24. Treatment on page 169.
 TaxonIllustrator 
FNA24 P67 xAchnella pg 170.jpeg×achnella caducaCindy Roché

Plants perennial; cespitose, not rhizomatous. Culms to 90 cm, erect, glabrous, not branching at the upper nodes; prophylls shorter than the sheaths. Sheaths mostly glabrous, margins sparsely ciliate, hairs longer distally; cleistogenes not present in the basal sheaths; collars without tufts of hair at the sides; auricles absent; ligules scarious, glabrous; blades of basal leaves to 40 cm long, 1-1.5 mm wide, convolute when dry, tapering to the narrowly acute apices, flag leaf-blades longer than 10 mm, bases about as wide as the top of the sheaths. Inflorescences panicles. Spikelets 6-8.5 mm, with 1 floret; rachillas not prolonged beyond the base of the floret; disarticulation above the glumes, beneath the floret. Glumes saccate-lanceolate, tapering from above midlength into elongate apices, midveins extending to or nearly to the apices, apices narrowly acute to acuminate; lower glumes 6-8.5 mm; upper glumes 6.5-7.5 mm, slightly narrower than the lower glumes; florets 4-5 mm, lengths more than 3 times the widths; calluses about 0.7 mm, blunt; lemmas coriaceous, evenly hairy throughout, hairs 1-2 mm, apical hairs not longer than those below; awns twisted, not or once-geniculate, readily deciduous; paleas more than 2/3 as long as the lemmas, veins ending at the apices; anthers poorly developed, indehiscent, sometimes with 1 or 2 penicillate hairs.

Distribution

Alta., B.C., Man., N.W.T., Sask., Yukon, Mont., N.Dak., Nebr.

Discussion

×Achnella comprises sterile hybrids between Achnatherum and Nassella. Only one such hybrid is known; it is restricted to the Flora region.

Lower Taxa

"decumbent" is not a number."+timesthewidths" is not declared as a valid unit of measurement for this property.

... more about "×achnella"
membranous +  and scarious +
indehiscent +
3 +  and 1 +
awned +, bifid +, bilobed +  and entire +
narrowly acute +  and acuminate +
Mary E. Barkworth +
Barkworth +
1 (?) +  and 3 (?) +
subterminal +  and eccentric +
not once-geniculate +
0.3 cm3 mm <br />0.003 m <br /> (30 cm300 mm <br />0.3 m <br />) +
keeled +  and rounded +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
not evident +
cross +, linear +  and narrowly lanceolate +
spikelike +
well-developed +
0.7 cm7 mm <br />0.007 m <br /> (?) +
not branching +
perennial +  and annual +
0 cm0 mm <br />0 m <br /> (90 cm900 mm <br />0.9 m <br />) +
not woody +
Alta. +, B.C. +, Man. +, N.W.T. +, Sask. +, Yukon +, Mont. +, N.Dak. +  and Nebr. +
0 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
sometimes longer +
compressed +  and terete +
1-10-veined +
subtending +
tapering +  and saccate-lanceolate +
membranous +
uncinate +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
solid +  and hollow +
basally concentrated +  and evenly distributed +
40 cm400 mm <br />0.4 m <br /> (?) +
0.1 cm1 mm <br />0.001 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
ovate +, rectangular +  and lanceolate +
coriaceous +
inconspicuous +
lanceolate +
fleshy +  and membranous +
0.6 cm6 mm <br />0.006 m <br /> (0.85 cm8.5 mm <br />0.0085 m <br />) +
concealed +  and prominent +
2 +  and 1 +
pubescent +  and glabrous +
well-developed +
/3 +  and 2 +
reduced +
dry +  and fleshy +
not prolonged +
johnson1943b +
1 +  and 60 +
unisexual +  and bisexual +
laterally compressed +  and terete +
0.6 cm6 mm <br />0.006 m <br /> (0.85 cm8.5 mm <br />0.0085 m <br />) +
1 +  and 3 +
simple +  and compound +
2 (?) +  and 3 (?) +
Gramineae +
×achnella +
Poaceae tribe Stipeae +
membranous +
0.65 cm6.5 mm <br />0.0065 m <br /> (0.75 cm7.5 mm <br />0.0075 m <br />) +
slightly narrower +
inconspicuous +
plant +  and cespitose +
aquatic +  and terrestrial +
12 +, 11 +, 10 +, 8 +  and 7 +