Author
Berdahl, John | |
Kronberg, Scott | |
Hendrickson, John | |
KARN, JAMES - RETIRED,USDA-ARS |
Submitted to: Grassland International Congress Proceedings
Publication Type: Proceedings Publication Acceptance Date: 11/18/2004 Publication Date: 6/1/2005 Citation: Berdahl, J.D., Kronberg, S.L., Hendrickson, J.R., Karn, J.F. 2005. Row spacing and productivity of Russian wildrye pastures in semiarid environments. p. 434. IN: F.P. O'Mara et al. (ed.). Proc. XX International Grassland Congress. Dublin, Ireland. 26 June - 1 July, Wageningen Academic Publishers. Interpretive Summary: Row spacings of 24 inches or more have been recommended for Russian wildrye in seeded pastures in semiarid climates to sustain forage yields in dry years. However, wide row spacings also promote weed invasion, soil erosion, and elevated plant crowns that result in a rough, 'washboard' ground surface. Four Russian wildrye cultivars and experimental strains were evaluated in rows spaced from 6 to 36 inches apart in 6-inch increments at the Northern Great Plains Research Laboratory, Mandan, ND. Yields tended to be greater for the 6-inch row spacing than the other spacings when the tests were newly established, but differences among row spacings diminished in succeeding years and were essentially equal by the third production year. Differences in crude protein among row spacings were not consistent over years. Results from this study will be used in establishing new guidelines that reduce row spacing in seeded Russian pastures from the currently recommended 18 to 24 inches to 6 to 18 inches. Technical Abstract: Row spacings of 60 cm or more have been recommended in semiarid regions for seeded pastures of Russian wildrye [Psathyrostachys juncea (Fisch.) Nevski] to sustain forage yields in dry years. Wide row spacings also promote weed invasion, soil erosion, and elevated plant crowns that result in a rough ground surface. This study was conducted to evaluate the relationship between row spacing and productivity of Russian wildrye at two semiarid sites in the northern Great Plains. Four cultivars and experimental strains were seeded in rows spaced from 15 to 90 cm apart in 15-cm increments. Dry matter yields varied among years at both sites, primarily in response to precipitation. Yields tended to be greater for the 15-cm row spacing than the other spacings when the tests were newly established, but differences among row spacings diminished in succeeding years and were essentially equal by the third production year. Regrowth forage had greater crude protein concentrations than the initial July harvest at the hard-dough stage of development. Differences in crude protein concentration among row spacings were not consistent over years. Potential weed invasion and other problems would negate any advantage for row spacings greater than 45 cm. |