Browse on keywords: crop rotation PA
Search results on 06/19/13
643. Baker, V.W. and I.P. Swanson. 1962. Economic effects of a grass-legume rotation in Palouse wheat-pea area.. WA Agr. Expt. Sta. Circular #183.
Farms using a grass-legume rotation show important economic advantages over other farms in comparison of 5 year data from 3 pairs of Palouse farms. T: Amount of cropland by type of crop. Average annual crop production. Cost inputs and income per cropland acre. Calculated erosion losses.
765. Benson, V., W. Goldstein, D. Young, J. Williams, and C. Jones. 1988. Impacts of cropping practices on nitrogen use and movement.. Proc. Intl. Conf. on Dryland Farming.
Conventional and PALS practices were used as inputs for the EPIC model to simulate the effects of the systems over 108 years on an Athena soil. Total erosion over 108 yr under PALS was 40% less than the conventional system. Nitrogen loss through water was 25% less under PALS than conventional. Percolation loss of N was zero for both systems. Neither system had significant increase or decrease in yields after 108 yr of erosion.
1617. Doran, J., D. Fraser, M. Culik, and W. Liebhardt. 1987. Influence of alternative and conventional agricultural management on soil microbial processes and nitrogen availability.. Am. J. Alternative Agriculture 2:99-106.
Differences in soil biological factors between management systems (conventional cash grain; legume/cash grain; grain/forage plus manure) were related primarily to crop characteristics and, to a lesser extent, to soil physical properties. The use of ag chemicals had little effect on microbial populations, their activities, or the cycling of N. Competitiveness of alternative systems employing legumes as N sources for grain crops may depend largely on the grower's ability to synchronize supplies of available soil N with periods of maximum uptake by grain crops.
1819. Elliott, L.F. (ed.). 1987. STEEP - Conservation concepts and accomplishments.. Washington State Univ. Publ., 662pp..
A compilation of 48 papers covering: tillage and plant maagement; erosion and runoff predictions; plant design; pest management; socio-economic; integrated systems; technology transfer for cropping systems; 22 technical notes. T: many
2200. Goldstein, W.A. and Young, D.L.. 1987. An agronomic and economic comparison of a conventional and a low-input cropping system in the Palouse.. Amer. J. Alternative Agriculture 2(2):51-56.
Describes the results of Goldstein's work with the pea-medic/medic/wheat rotation in comparison with a wheat/barley/wheat/pea rotation. Variable costs for PALS were 44% of those in the conventional system. The conventional system generated higher gross returns, and higher net returns under subsidized prices, while the PALS was economically attractive at market prices.
2965. Ingham, I.M.. 1924. Effect of legumes in rotation upon the nitrogen content of the soil.. M.S. Thesis, Washington State College, Pullman, WA.
Soils at WSC farm were sampled to show residual effect of legumes upon following crops of wheat, and upon the N content of soil. T: Effect of legumes upon the following crops as shown by yields of wheat. Changes in the N content of soils after 5 years of crop rotations. Influence of various rotations on the N/C ratio of the soil.
3570. Kent, R.L.. 1957. Conservation crop rotations in the PNW.. J. Soil Water Conservation, 12(6): 269.
Experimental data and observations indicate that crop rotations with grass and legumes is needed in the wheat-pea area. Also of importance are strip croping, contour operation, stubble mulching, early seeding of winter wheat. T: comparison of OM, water loss, soil loss from virgin land and crop land.
5761. Reganold, J.P.. 1988. Comparison of soil properties as influenced by organic and conventional farming systems.. Am. J. Alt. Agric., 3(4):144-155.
This paper summarizes data from previous and current studies on two adjacent farms, one organically managed and the other conventionally managed, in the Palouse region of eastern Washington. The 320-hectare organic farm has been managed without the use of commercial fertilizers and only limited use of pesticides since the farm was first plowed in 1909. The 525-hectare conventional farm, first cultivated in 1908, began receiving recommended rates of commercial fertilizers and pesticides in 1948 and the early 1950's, respectively. The organically-farmed Naff silt loam soil had significantly higher organic matter, cation exchange capacity, total nitrogen, extractable potassium, water content, pH, polysaccharide content, enzyme levels, and microbial biomass than did the conventionally-farmed Naff soil. Also, the organically-farmed soil had significantly lower modulus of rupture, more granular structure, less hard and more friable consistence, and 16 centimeters more topsoil. This topsoil difference between farms was attributed to significantly greater erosion on the conventionally-farmed soil between 1948 and 1985. The difference in erosion rates between farms was most probably due to their different crop rotation systems; i.e., only the organic farm included a green manure crop in its rotation, and it had different tillage practices. These studies indicate that, in the long-term, the organic farming system was more effective than the conventional farming system in maintaining the tilth and productivity of the Naff soil and in reducing its loss to erosion.
5771. Reganold, J.P., L.F. Elliott and Y.L. Unger. 1987. Long-term effects of organic and conventional farming on soil erosion.. Nature, 330(26 Nov.):370-372.
The long-term effects (since 1948) of organic and conventional farming on selected properties of the same soil are compared. The organically-farmed soil had significantly higher organic matter content, thicker topsoil depth, higher polysaccharide content, lower modulus of rupture and less soil erosion than the conventionally-farmed soil. This study indicates that, in the long term, the organic farming system was more effective than the conventional farming system in reducing soil erosion and, therefore, in maintaining soil productivity. T: Mean values of conventional and organic farm soil properties.
6339. Sloan, S.L.. 1939. Soil-conserving and soil-improving crop rotations for the Palouse.. J. Am. Soc. of Agronomy 31(4):300.
Evaluates cropping systems and makes recommendations.