Submitted to: Journal of Range Management
Publication Type: Peer reviewed journal
Publication Acceptance Date: 11/3/2001
Publication Date: 9/1/2002
Citation: HAFERKAMP, M.R., GRINGS, E.E., HEITSCHMIDT, R.K., MACNEIL, M.D. QUALITY AND PERSISTENCE OF FORAGES IN THE NORTHERN GREAT PLAINS. JOURNAL OF RANGE MANAGEMENT. 2002. v. 55. p. 482-487. Interpretive Summary: Seeding perennial cool-season grasses can be used to extend grazing seasons on rangelands. We evaluated yearling livestock performance and stand persistence of three released varieties of wheatgrasses seeded in the Northern Great Plains. We found livestock performance grazing these pastures in spring varied among the varieties. Gains were similar in 1997; gains were greater on Hycrest than Rosana in 1998; and gains were greater on Hycrest and Rosana than Luna in 1999. In 1 out of 3 years Hycrest crested wheatgrass provided more forage than Rosana western wheatgrass and would have allowed an increase in livestock numbers during spring. We also found that persistence of Luna pubescent wheatgrass is a problem in the 13 inch precipitation zone.
Technical Abstract: Seeding perennial cool-season grasses can be used to extend grazing seasons on rangeland. Few available cultivars have been evaluated for livestock performance. Our objective was to evaluate livestock performance and persistence of three cultivars of wheatgrasses (WG). Twice replicated 3-ha pastures were seeded to 'Rosana' western WG (Pascopyron smithii), 'Luna' pubescent WG (Elytrigia intermedia), and 'Hycrest' crested WG (Agropyron spp.) in autumn 1994. Yearling steers (n = 8) grazed from May 9 to June 12, 1997 and April 24 to June 15, 1998. Yearling heifers grazed from April 27 to June 18, 1999. Hycrest produced the largest herbage yield in spring 1997 (912 kg/ha) and 1998 (1,223 kg/ ha) (P < 0.05); however, by spring 1999 yields were similar among cultivars (613 kg/ha). Digestible OM yield of available forage did not differ among pastures of seeded species, but declined (P < 0.05) from May to June each year. Crude protein yield varied among cultivars (P < 0.05) in April and May 1998 and May 1999; however, no clear trends emerged. Crude protein yields consistently decreased from April-May to June. Diets generally consisted of > 40% green Hycrest and Rosana but < 40% Luna. Average daily gains were similar among cultivars in 1997, but ADG were greater (P < 0.05) on Hycrest (1.28 kg/d) than Rosana (1.03 kg/ d) in 1998. Gains on Hycrest (0.74 kg/d) and Rosana (0.78 kg/d) were greater (P < 0.05) than on Luna (0.52 kg/d) in 1999. Data from this study and others clearly show that in some years, crested WG provides more forage in spring than native species like western WG, and will allow an increase in livestock numbers. This happened in 1 of 3 yr in