Browse on keywords: organic matter WA
Search results on 12/08/13
8926. Lunt, H.A.. 1923. Some factors affecting soil organic matter decomposition.. M.S. thesis, Washington State College, Pullman, WA.
1172. Campbell, C.A., K. Bowren, G. LaFond, H. Janzen, and R.P. Zentner. 1989. Effect of crop rotations on soi organic matter in two black chernozems.. Soil and Crop Workshop, Univ. Saskatchewan, Saskatoon, Feb. 1989.
1657. Doughty, J.L., F.D. Cook, and F.G. Warder. 1954. Effect of cultivation on the organic matter and nitrogen of brown soils.. Canadian J. Agr. Sci. 34:406-411.
Over 14 yr of cropping, soils lost 26% of OM and 33% of total N. Only part of the N loss is accounted for by crop removal. Some N is lost by leaching, also some gaseous loss of N other than as ammonia.
2137. Fulmer, E.. 1896. Some notes concerning the nitrogen content of soils and humus.. WA Agr. Expt. Sta. Bull. #23.
In Whitman Co., the organic matter in cultivated soils ranged from 3-8%. The first part of this bulletin is an excellent discussion on soil N components. "The author became concerned that humus was not receiving the attention that its importance as a factor in soil fertility demanded. Only a small proportion of soil analysis has included a determination of humus..." T: Shows fractions of soil N for soils from various counties - including Whitman Co. includes: Humus; Total N in soil; Organic N; N in humus; Organic matter.
2683. Holtz, H.F. and S.C. Vandecaveye. 1938. Organic residues and nitrogen fertilizers in relation to the productivity and humus content of a Palouse silt loam.. Soil Sci 45: 143-163.
T: soil carbon, soil nitrogen
2735. Horner, G.M., M.M. Oveson, G.O. Baker, and W.W. Pawson.. 1960. Effect of cropping practices on yield, soil organic matter and erosion in the Pacific Northwest wheat region.. PNW Technical bulletin 1; USDA-ARS and Ag. Expt. Sta.'s of ID, OR, WA.
Summary of soil management experiments conducted over 40 yrs at six experiment stations. Covers: crop rotation, fertilization, and use of organic material. Some results: sweetclover and alfalfa were more effective than other legumes in increasing wheat yield. Yields of wheat were markedly affected by the sequences of cropping. Return of straw to soil decreased yields slightly under low N conditions. Organic and mineral N had no effect on yields in low precip. zones. Also covers runoff and erosion. T: many, eg.: effect of crop rotations on crop yield; crop yield as affected by grass/clover; effect of OM on wheat yield.
2995. Jacklin, A.W.. 1936. Crop rotations.. USDA-SCS Agronomy - Range Meetings, Pullman, WA #580.
Use legume grass mix in higher rainfall area, grasses in drier areas; rotations are typically 4-7 yr long; perennials can help check the weed problem; subsoiling effect of alfalfa, sweetclover reduces erosion and run-off; grass roots superior in soil aggregation.
3013. Stroo, H.F., K.L. Bristow, L.F. Elliott, R.I. Papendick, and G.S.Campbell. 1989. Predicting rates of wheat straw decomposition.. Soil Sci. Soc. Am. J. 53:91-99.
Predicting the rate and extent of decomposition of residues at the soil surface is necessary to evaluate the impacts of minimum tillage practices on erosion control and thus ensure the most effective use of residues. A mechanistic model simulating the decomposition of surface-managed winter wheat residues was developed and model predictions were compared to results from field studies of decomposition rates.
3080. Tangren, G.V.. 1979. Subsoil bulk densities in some Whitman county small grain fields.. M.S. Thesis, Dept. of Agronomy and Soils, WSU, Pullman, WA.
3210. Bhatti, A.U.. 1990. Spatial variability and geostatistical estimation of soil properties and wheat yield on eroded lands in the Palouse region.. Chpt. 3, PhD. Dissertation, Dept. of Agronomy & Soils, Washington State Univ., Pullman, WA 99164.
Spatial variability of organic matter, soil P, and wheat yields was studied using classical statistical and geostatistical approaches on two commercial wheat farms in the Palouse region of eastern Washington. Geostatistics indicated strong spatial relationship of soil properties and wheat yields with a range of influence of 50-200 m. The two sites differed greatly in spatial patterns due primarily to differences in topography and the extent of erosion and topsoil loss. As a consequence of topsoil loss and reductions in organic matter, it was demonstrated that spatial patterns in yield and soil phosphorus were strongly correlated with organic matter patterns. Remote sensing of soil organic matter and the use of geostatistics offers a way to quickly assess spatial patterns in grain yield and available phosphorus.