Performance of perennial cool-season forage grasses in diverse soil moisture environments, Southern High Plains, USA

A continuing need exists to evaluate grasses for irrigated pastures in new and marginal environments. Persistence and yield of Altai wildrye, Leymus angustus (Trin.) Pilg.; beardless wildrye, L. triticoides (Buckley) Pilg.; creeping foxtail, Alopecurus arundinaceus Poir.; grazing bromegrass, Bromus stamineus E. Desv.; intermediate-pubescent wheatgrass, Elytrigia intermedia (Host) Nevski; meadow bromegrass, B. riparius (Rehmann); meadow fescue, Festuca pratensis (Huds.); orchardgrass, Dactylis glomerata (L.); prairie bromegrass, B. willdenowii (Kunth), syn. B. catharticus Vahl var. catharticus; reed canarygrass, Phalaris arundinacea L.; RS wheatgrass, E. repens var. repens L. Desv. ex B.D. Jackson x Pseudoroegneria spicata (Pursh) A. Love; Russian wildrye, Psathyroslachys juncea (Fisch.) Nevski; smooth bromegrass, It. inermis Leyss.; fall fescue, E arundinacea Schreb.; tall wheatgrass, E. elongata (Host) Nevski; and western wheatgrass, Pascopyrum smithii (Rybd.) A. Love, sown in late summer 1997, were measured from 1999 to 2001 at Tucumcari, NM. Soil moisture treatments were (i) furrow irrigated once before each harvest, which is typical management; (ii) typical irrigation plus irrigated monthly during winter, and (iii) poorly drained, saline/sodic soil, irrigated less than once per cutting. Russian wildrye, RS wheatgrass, tall fescue. tall wheatgrass, and western wheatgrass maintained ground cover across soil moisture treatments. Stand development by Altai wildrye and smooth bromegrass was inconsistent across soil moisture treatments, but eventually complete. Beardless wildrye established stands only in poorly drained soil, while intermediate-pubescent wheatgrass and meadow bromegrass did not establish well in that soil. No other species established or maintained satisfactory stands after 3 yr in any soil moisture treatment. Winter irrigation increased early-season yield of intermediate-pubescent wheatgrass, but decreased late-season yields of several species, especially Altai wildrye. Distribution of tall wheatgrass and Altai wildrye yield appear complementary, and a binary mixture might provide uniform season-long yields in this region.