Agropyron

Thickspike wheatgrass Agropyrum dasystachyum, copyright Matt Lavin.

Belongs within: Pooideae.

Agropyron, the crested wheat-grasses, is a genus of perennial grasses native to Eurasia, though widely introduced elsewhere for pasture. Examples include couch grass A. repens which spreads by creeping rhizomes that propagate readily, leading to it becoming regarded as an invasive weed in many regions.

Characters (from Flora of North America Editorial Committee 2007): Plants perennial; densely to loosely caespitose, sometimes rhizomatous. Culms 25-110 cm, geniculate or erect. Sheaths open; auricles usually present; ligules membranous, often erose. Inflorescences spikes, usually pectinate; middle internodes 0.2-3(5.5) mm, basal internodes often somewhat longer. Spikelets solitary, usually more than three times as long as the internodes, usually divergent or spreading from the rachis, with 3-16 florets; disarticulation above the glumes and below the florets. Glumes shorter than the adjacent lemmas, lance-ovate to lanceolate, 1-5-veined, asymmetrically keeled, secondary keel sometimes present on wider side, keels glabrous or with hairs, hairs not tufted, apices acute and entire, sometimes awned, awns to 6 mm; lemmas 5-7-veined, asymmetrically keeled, acute to awned, awns to 4.5 mm; paleas from slightly shorter than to exceeding the lemmas, bifid; anthers 3, 3-5 mm, yellow. Caryopses usually falling with lemmas and paleas attached. x = 7. Haplome P.

<==AgropyronC06
    |--A. bakeriV72
    |--A. dasyanthemumV72
    |--A. desertorum [incl. A. cristatum, A. fragile, A. sibiricum]H93
    |--A. enysii Kirk 1905 [incl. Asprella aristata Petrie 1894]C06
    |--A. multiflorum Kirk 1897 [=Triticum multiflorum]C06
    |    |--A. m. var. multiflorumC06
    |    `--A. m. var. longisetum Hackel in Cheeseman 1906C06
    |--A. pectinatum [=Festuca pectinata, Triticum pectinatum, Vulpia pectinata; incl. T. brownei]B78
    |--A. pectiniformeV72
    |--A. repensS00 [=Elytrigia repensH93, Triticum repensC06]
    |    |--A. r. var. repensS06
    |    |--A. r. var. scabrifoliumS06
    |    `--A. r. var. vulgare Doell. 1857S06
    |--A. scabrum (Labill.) Beauv. 1812G52 (see below for synonymy)
    |--A. velutinum [=Triticum velutinum]B78
    `--A. youngii (Hook.f.) Cheeseman 1906 [=Triticum youngii]C06

Agropyron scabrum (Labill.) Beauv. 1812G52 [=Festuca scabraC06, Triticum scabrumC06, Vulpia scabraB78; incl. Anthosachne australasicaB78, Festuca billardieriB78, Vulpia braunianaB78, Agropyron scabrum var. brevisetaB78, Festuca brownianaB78, Vulpia brownianaB78, F. rectisetaB78, V. rectisetaB78, Agropyron squarrosumA27]

*Type species of generic name indicated

References

[A27] Andersen, J. C. 1927. Popular names of New Zealand plants. Part 2. Transactions and Proceedings of the New Zealand Institute 57: 905–977.

[B78] Bentham, G. 1878. Flora Australiensis: A description of the plants of the Australian Territory vol. 7. Roxburghiaceae to Filices. L. Reeve & Co.: London.

[C06] Cheeseman, T. F. 1906. Manual of the New Zealand Flora. John Mackay, Government Printer: Wellington.

[G52] Gardner, C. A. 1952. Flora of Western Australia vol. 1 pt 1. Gramineae. William H. Wyatt: Perth.

[H93] Hickman, J. C. (ed.) 1993. The Jepson Manual: Higher Plants of California. University of California Press: Berkeley (California).

[S00] Siddiqi, M. R. 2000. Tylenchida: Parasites of plants and insects 2nd ed. CABI Publishing: Wallingford (UK).

[S06] Stuckert, T. 1906. Segunda contribución al conocimiento de las gramináceas Argentinas. Anales del Museo Nacional de Buenos Aires, serie 3, 6: 409–555.

[V72] Voss, E. G. 1972. Michigan Flora. Part I. Gymnosperms and Monocots. Cranbrook Institute of Science and University of Michigan Herbarium.

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