Family: Poaceae |
Mary E. Barkworth Plants perennial; cespitose or not, sometimes rhizomatous. Culms 10-250 cm, usually erect. Sheaths glabrous or ciliate; auricles 0.2-1.5 mm or absent; ligules membranous; blades convolute or flat. Inflorescences terminal, distichous spikes, usually not disarticulating at maturity; middle internodes 7-30 mm; disarticulation usually beneath the florets and tardy, occasionally in the rachises. Spikelets 1-3 times the length of the middle internodes, solitary, appressed to ascending, often trullate and arching outwards at maturity. Glumes oblong to lanceolate, stiff, indurate to coriaceous, glabrous or with hairs, keeled or rounded at the base, usually more strongly keeled distally than below, margins often with a hyaline margin, apices truncate to acute, sometimes mucronate, unawned, without lateral teeth; lemmas 5-veined, coriaceous, glabrous or with hairs, truncate, obtuse, or acute, sometimes mucronate or awned, awns to 3 cm; anthers 3, 2.5-12 mm. x = 7. Name from the Greek thino, a shore weed, and pyros, wheat. SELECTED REFERENCES Assadi, M. 1994. The genus Elymus L. (Poaceae) in Iran: Biosystematic studies and generic delimitation. Ph.D. dissertation, Lund University, Lund, Sweden. 104 pp.; Barkworth, M.E. 1997. Taxonomic and nomenclatural comments on the Triticeae in North America. Phytologia 83:302-311; Darbyshire, S.J.1997. Tall Wheatgrass, Elymus elongatus subsp. ponticus, in Nova Scotia. Rhodora 99:161-165; Jarvie, J.K. 1992a. Taxonomy of Elytrigia sect. Caespitosae and sect. Junceae (Gramineae: Triticeae). Nordic J. Bot. 12:155-169; Jarvie, J.K. and M.E. Barkworth. 1992b. Morphological variation and genome constitution in some perennial Triticeae. Bot. J. Linn. Soc. 108:167-189; Liu, Z.W. and R.R.-C. Wang. 1993. Genome constitutions of Thinopyrum curvifolium, T. scirpeum, T. distichum, and T. junceum (Triticeae: Gramineae). Genome 36:641-651; Ogle, D. 2001. Intermediate wheatgrass, Thinopyrum intermedium (Host) Barkworth & D.R. Dewey. Plant Fact Sheet, U.S. Department of Agriculture, Natural Resource Conservation Service Plant Materials Program. http://plants.usda.gov. |