Browse on keywords: crop rotation WA moisture
Search results on 09/20/18
826. Bezdicek, D. and R. Lockerman. no date. Crop rotation and the response of cereal crops to nitrogen in the PNW. unpublished.
Experiments conducted at Pullman, WA and Bozeman, MT. Year 1 - legumes (rainfall -Pullman 500 mm, Bozeman 480 mm). Year 2 -Pullman winter wheat + N (rainfall 350 mm); Bozeman barley + N (rainfall 200 mm). Compared fababean, pea, lentil, chickpea, fallow at both locations. Pullman legumes were used as green manure, Bozeman legumes were harvested for seed. N fertilizer equivalents ranged from 30-86 kg/ha N at Pullman (fallow = 125) and from 27-81 kg/ha N at Bozeman (fallow = 53). All cereals responded to added N, although less so at Pullman. More N was removed in seed than was fixed. Seed legumes appeared to fix 50-100 kg/ha N. The rotation effect was more significant at Pullman. T: cereal yields; fertilizer N equivalent; moisture depletion.
1180. Campbell, C.A., R.P. Zentner and P.J. Johnson. 1988. Effect of crop rotation and fertilization on the quantitative relationship between spring wheat yields, available soil moisture, and precipitation.. Canadian J. Soil Sci., 68(1):1-16.
The effects of crop rotation and fertilization on the quantitative relationship between spring wheat yields, available soil moisture, and growing season precipitation were determined. Stubble-seeded wheat required 68 mm of moisture to produce the first kilogram per hectare of grain; fallow-seeded wheat required about 46mm. The lower threshold level of MU for grain production decreased from about 140mm to the values cited above; this has resulted in substantially greater moisture use efficiency in recent years likely due to better, more timely crop mangement and the improved cereal varieties.
3589. Kirby, E.M.. 1987. Soil moisture depletion and wheat yield response from annual legumes in the Pacific Northwest. M.S. Thesis, Dept. of Agronomy and Soils, WSU, Pullman, WA.
Legumes included chickpea, spring pea, lentil, fababean, sweetclover, rose clover, black medic, barrel medic. Sweetclover depleted more soil moisture than other legumes. Wheat yield increased following legumes relative to that after barley. Highest yield followed legume green manure with additional fertilizer N. Grain yields were similar for fallow, lentil, pea, chickpea, and fababean. T: soil moisture depletion; yield, N content of soil and grain.
5215. Pierce, F.J. and C.W. Rice. 1988. Crop rotation and its impact on efficiency of water and N use. p. 21-42.. IN: W.L. Hargrove (ed.). Cropping strategies for efficient use of water and nitrogen..
Crop rotations are viewed as beneficial, but not always economic, as long as commercial N supplies are unrestricted. True assessments of crop rotations are difficult due to their long term nature and indirect results. True assessments will only be obtained when all N pools are considered. There is a real lack of research that has determined either water or N use, and interaction as determined by crop rotations. The problem is one of funding and methodology. T: Distribution of organic N after 17 yr rotation.
5585. Ramig, R.E. and L.G. Ekin. 1987. Fallow systems for semiarid eastern Oregon and Washington.. OR Agr. Expt. Sta. Special Report 797, p.34.
7850. Koala, S.. 1982. Adaptation of Australian ley farming to Montana dryland cereal production.. M.S. Thesis, Dept. of Plant and Soil Sci., Montana St. Univ., Bozeman, MT 59717.
This study examined the potential to adapt the ley farming system used in Australia to dryland cereal production in Montana. The ley system alternates a grain crop with a self-seeding forage legume. The legumes tested in this study included 5 Australian medics, 7 subclovers, 2 lupins, fababean, and a native Montana black medic. One full cycle of the system was completed. All grain yields (spring wheat) were higher after the legumes than after fallow. Soil water to 120 cm was similar in all plots at wheat planting. The black medic treatment had the highest water use efficiency (100 kg grain/cm) and fallow the lowest (55 kg grain/cm). There were higher levels of soil nitrate after the legumes than after fallow. Re-establishment of the legumes after wheat ranged from 3 to 93% ground cover, with black medic being the highest. Overall, black medic from Montana performed best in this study.
9781. Wanser, H.M.. 1924. Effect of variations in the cropping system on the efficient utilization of precipitation and on resulting soil moisture.. M.S. thesis, Washington State College, Pullman, WA.