Agropyron Gaertn. in Novi Comment. Acad. Sci. Imp. Petropol. 14:539. 1770. Boiss., Fl. Or. 5:659. 1884, in part; Bor, Grasses Burma Ceyl. Ind. Pak. 655. 1960, in part; Boi in Towns., Guest & Al-Rawi, Fl. Iraq 9:208. 1968, in part; Bor in Rech.f., Fl. Iran. 70:150. 1970 (sect Agropyron only); Tzvelev, Poaceae URSS 143. 1976; Melderis in Tutin et al., Fl. Fur. 5:198. 1980.
Perennials, with or without rhizomes. Leaf-blades flat or convolute. Inflorescence a spike. Spikelets 3-10-flowered, pectinate or imbricate, strongly laterally compressed, solitary at the nodes of the tough rhachis; rhachilla disarticulating above the glumes and between the florets; glumes narrowly lanceolate to ovate-lanceolate, prominently keeled, with 1-2 inconspicuous lateral nerves, covering the backs of the lower florets; lemmas membranous, 5-nerved, keeled, awnless or shortly awned; palea 2-keeled, coarsely ciliate along the keels.
A genus of about 15 species in the Mediterranean region, eastern Europe, temperate Asia, Australia and New Zealand; 1 introduced species occurs in Pakistan.
The modern concept of Agropyron restricts it to those species with keeled glumes and, in many cases, pectinately arranged spikelets. All other species have been transferred to Elymus.
Agropyron cristatum (Linn.) Gaertn. is mentioned by Stewart in his Annotated Catalogue. Neither specimen cited has been seen, so the presence of this species in Pakistan remains unconfirmed. It is distinguished from Agropyron desertorum by its broader, usually ovate or oblong spike in which the spikelets are pectinately arranged, diverging from the axis at a very wide angle.
