Browse on keywords: fertility WA OR
Search results on 10/17/18
1292. Chaudhary, T.H.. 1976. The effect of nitrogen source and 2-chloro-6-(trichloromethyl) pyridine (N-Serve) on the nitrogen and sulfur nutrition of wheat.. Ph.D. Thesis, Dept. of Agronomy and Soils, Washington State Univ., Pullman, WA.
The effects of urea applications with and without the product N-serve were examined. N-serve considerably reduced the loss of NH4+-N to organic transformations, and resulted in much higher amounts that were available to plants. Some problem of N toxicity resulted, but this was presumed to also be related to a lack of sulfur. T: Many. e.g.:Changes in the organic N content of the soil and N uptake by plants. Amounts of NH4+-N and NO3--N in the soil in April and August. Dry-matter yields and percentage uptake of N and S.
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.
3725. Koehler, F.E.. 1959. Fertilizer interactions in wheat producing areas of eastern Washington.. Proceedings, 10th Ann. Fert. Conf. PNW, Tacoma, WA, p.19-21.
The most frequently observed nutrient interaction in the wheat producing area of eastern Washington is that between sulfur and nitrogen under annual cropping. Where no sulfur was added, yields were increased by about 8 bushels per acre, and 30 lbs N/ac resulted in slightly better yields than did 120 lbs. When one lb sulfur was added per acre, yield increases from nitrogen were about 15 bu/ac, and again there was little difference between the effects of 30 and 120 lbs of N. However, where the sulfur rate was 10 lbs/ac, the yield increase with 30 lb N was 20 bu/ac and that with 120 lb N was 30 bu/ac. In no case did sulfur alone appreciably increase yields.
3865. Leggett, G.E.. 1959. Relationships between wheat yield, available moisture and available nitrogen in eastern Washington dryland areas.. WA Agr. Expt. Sta. Bull. #609.
The purpose of this work is to demonstrate the relationships which exist between (1) available moisture and wheat yield and (2) available nitrogen and wheat yield. Using these relationships, it is possible to calculate the amount of fertilizer nitrogen necessary to obtain maximum wheat yield if the supply of available nitrogen in the soil and the amount of moisture available for the crop can be estimated. The results of 90 fertility experiments conducted on dryland wheat in eastern Washington during the period 1953-1957 were used to determine the relationship between wheat yield and available moisture. The results of 62 experiements were used to determine the relationship between wheat yields and available nitrogen. It is possible to calculate nitrogen fertilize recommendations from the results of soil tests for nitrate-nitrogen and available soil moisture by use of these relationships.
3885. Leggett, G.E., H.M. Reisenauer and W.L. Nelson. 1959. Fertilization of dryland wheat in eastern Washington.. WA Agr. Expt. Sta. Bull. #602.
This bulletin presents the results of 5 yrs of experimenting with the fertilization of wheat. During 1953-1957, 112 fertility experiments were conducted on dry land wheat throughout eastern Washington. Nitrogen fertilization significantly increased yields in 92 of the 112 experiments conducted. Whether nitrogen fertilization increased wheat yields depended largely on the amount of moisture available to the crop. Because of the decline in soil organic matter through years of cropping, the amount of available N released by soils is no longer adequate to support high wheat yields. The introduction of high yield varieties and improved tillage has increased yield potential, and this has increased the demand for N. Application rates (lb N/ac): <10" rainfall - 20-40; 10-15" - 20-60; >15" - 30-80. Different types of N fertilizer did not change yields. T: Summary of the effects of N on wheat yields, 1953-57; effect of N on yield from fallow ground.
5065. Patten, A.G.. 1982. Comparison of nitrogen and phosphorous flows on an organic and conventional farm.. M.S. Thesis, Dept. of Agronomy and Soils, WSU, Pullman, WA.
Two adjacent farms, one organically managed and the other conventionally managed, located in the Palouse region of eastern WA, were studied for 2 years. Soil organic matter, total N, extractable P, and extractable K tended to be higher in the top 30 cm of soil from the organic farm. Mineral nitrogen in the top 30 cm of soil from the conventional farm was higher than or equal to that of the organic farm. Average long-term changes calculated in soil N and P pools resulted in substantial deficits of 44 and 14 kg/ha/yr, respectively, for the organic farm and 23 and 5 kg/ha/yr for the conventional farm. However, nutrients deficits were not reflected in lower soil N and P levels in the plot area tested on the organic farm as compared to the plot area on the conventional farm.
5667. Rasmussen, P.E. and D.E. Wilkins. 1987. Winter wheat response to lime in a wheat-pea rotation.. OR Agr. Expt. Sta. Special Report 797, p. 31.
5675. Rasmussen, P.E. and D.E. Wilkins. 1988. Green pea response to lime in a wheat-pea rotation.. OR Agr. Expt. Sta. Special Report 827, p. 43.
6268. Sievers, F.J. and H.F. Holtz. 1926. The significance of N in soil organic matter relationships.. WA Agr. Expt. Sta. Bull. #206.
"...there is such a close relationship between soil productivity and soil organic matter that this relationship has long been used as a basis for determining soil fertility. ...should agricultural practices strive arbitrarily to increase or maintain OM so that larger yields may be obtained, or should they be so conducted that larger yields are the primary consideration, thus taking for granted that the necessary maintenance of OM will follow? The answer to this is governed quite as largely by economic as scientific relationships." This bulletin coins the adage "you maintain the N and you maintain it all." It provides detailed descriptions of: moisture/OM relationships; N/C ratios; OM decomposition; maintainance of OM; crop residues.