| Taxon | Illustrator ⠉ | |
|---|---|---|
 | Eremopyrum triticeum Eremopyrum bonaepartis Eremopyrum orientale | Cindy Roché Cindy Roché Cindy Roché |
Plants annual. Culms 3-40 cm, geniculate. Sheaths open for most of their length; auricles present, often inconspicuous; ligules 0.4-2 mm, membranous, truncate; blades 1-6 mm wide, flat, linear. Inflorescences distichous spikes, 0.8-4.5 cm, with 1 spikelet per node, usually erect when mature; rachis internodes flat, margins glabrous or with hairs, hairs white; middle internodes 0.5-3 mm; disarticulation in the rachises, at the nodes beneath each spikelet, or at the base of each floret. Spikelets 6-25 mm, including the awns, more than 3 times the length of the internodes, divergent, laterally compressed, with 2-5 bisexual florets, sterile florets distal or absent. Glumes equal, 4-19 mm, including the awns, coriaceous, becoming indurate, 1-keeled initially, sometimes 2-keeled at maturity, keels glabrous or hairy, never with tufts of hair, bases slightly connate, apices tapering to a sharp point or straight awn; lemmas 5-24 mm, coriaceous, rounded basally, keeled distally, 5-veined, unawned or shortly awned; paleas usually shorter and thinner than the lemmas, 2-keeled, ciliate or scabrous distally, keels sometimes prolonged into 2 toothlike appendages; anthers 3, 0.4-1.3 mm, yellow. Ovaries pubescent; styles 2, free to the base, x = 7. Haplomes F, Xe.
Distribution
Colo., N.Mex., Wash., N.Y., Utah, Wyo., Nebr., Oreg., Mont., Alta., B.C., Man., Sask., Idaho, Ariz., Nev.
Discussion
Eremopyrum includes 5-10 species that grow in steppes and semidesert regions from Turkey to central Asia and Pakistan. Three species have been found in North America; only E. triticeum is widepsread. In their native ranges, species of Eremopyrum are valuable fodder on ephemeral spring pastures.
Selected References
Key
| 1 | Glumes 1-veined and 2-keeled at maturity; lemmas of the first floret in each spikelet pubescent on the lower 1/2, glabrous distally, the other lemmas glabrous; disarticulation beneath the florets, sometimes at the base of the spikes | Eremopyrum triticeum |
| 1 | Glumes usually 3-5-veined and 1-keeled; lemmas of all florets alike in their pubescence or lack thereof; disarticulation at the rachis nodes. | > 2 |
| 2 | Glume bases straight; spikes 1.3-2.8 cm wide | Eremopyrum bonaepartis |
| 2 | Glume bases arcuately curved; spikes 0.9-1.8 cm wide | Eremopyrum orientate |
"decumbent" is not a number."+timesthelengthof" is not declared as a valid unit of measurement for this property.