Browse on keywords: fertility OR pH
Search results on 12/17/18
161. Albrecht, W. A. and N.C. Smith. 1939. Calcium in relation to phosphorous utilization by some legumes and grasses.. Soil Sci. Soc. Am. Proc., 4:260-265.
9609. Freyman, S. and M.S. Kaldy. 1979. Relationship of soil fertility to cold hardiness of winter wheat crowns.. Can. J. Plant Science 59:853-855..
In two controlled-environment experiments, N fertilizer applied to a Dark Brown prairie soil decreased cold hardiness of winter wheat, while P applied in the absence of N had little effect. When applied together, P counteracted the effect of N and produced plants as hardy as those that had received no fertilizer. The soil was rich in K; consequently applicaton of additional amounts of this element had no effect on cold hardiness. The correlation coefficient between dry weight of crowns and cold hardiness was not significant, but that between water content and LT was highly significant.
272. Allmaras, R.R., K. Ward, P.E. Rasmussen and C.R. Rohde.. 1978. Soil acidification from long-term use of ammonium-type nitrogen fertilizers.. OR Agr. Expt. Sta. Progress Report Misc. #78-4, p.55-58.
Long term use of ammonium fertilizers has reduced pH in the plowlayer in proportion to the rate of application; no noticeable difference in 12-18 zone of soil; about 50% of the applied fertilizer was lost, perhaps by denitrification; 1 T of pure limestone raised the pH by 0.5 unit; liming to pH 6.2 improved pea growth and increased soil water storage; potential increase infiltration and reduce erosion with liming. T: pH x depth, N rate, lime requirement.
1688. Douglas, C.L.. 1983. Silicic acid and oxidizable carbon movement in a Walla Walla silt loam.. Ph.D Thesis, Oregon State Univ., Corvallis, OR. 75pp..
This study shows that use of ammonia fertilizers over the past 40 yrs, and particularly anhydrous ammonia in the past 15, has resulted in a more acid plow layer. The decrease in pH has caused soluble silica to leach out of the plow layer and led to cementation of the plow pan layer below 15 cm. The result is reduced water infiltration, increased water runoff and soil erosion, and increased soil water evaporation. Corrective applications of hydrated lime are explored. T: Mean silicic acid concentration in leachates from 15 cm soil layers as affected by long term N treatments. Long-term N and residue management effects on soluble carbon movement in four 15 cm layers. Soil pH and carbon addition effects on silicic acid concentration and transfer from the 0-15 cm layer.
2617. Hill, K.W.. 1954. Wheat yields and soil fertility on the Canadian prairies after a half century of farming.. Soil Sci. Soc. Am. Proc. 18:182-184.
T: soil properties X rotation; wheat yields X time
3070. Tanaka, D.L. and J.K. Aase. 1989. Influence of topsoil removal and fertilizer application on spring wheat yields.. Soil Sci. Soc. Am. J. 53:228-232.
In 3 of 5 years, soil removal treatments reduced spring wheat yields an average of 9, 28, and 45% for 0.06, 0.12, and 0.18 m soil removal treatments, respectively, over all fertilizer treatments. The data suggest that P was the most limiting nutrient and additions of N fertilizer without P resulted in small yield increases.
3117. Rasmussen, P.E.. 1989. unpublished data on soil pH from long-term plots at Pendleton, OR. Columbia Basin Agr. Res. Center, P.O. Box 370, Pendleton, OR 97801.
Plots have received various tillage and fertility treatments since 1931. The original pH (1:2 water) was 6.3. Addition of 10 T/ac manure every other year raised the pH to 6.9, while addition of 1 T/ac pea vines raised it to 6.5. Fall burn lowered the pH to 6.2. The decline in soil pH was essentially linear with increasing total N fertilizer added over the years. A nearby permanent pasture had a pH of 7.3.
4518. Molla, M.A.Z., A.A. Chowdhury, A. Islam and S. Hoque. 1984. Microbial mineralization of organic phosphate in soil.. Plant and Soil, 78:393-399.
Phosphate-dissolving microorganisms were isolated from non-rhizosphere and rhizosphere of plants. These isolates included bacteria, fungi and actinomycetes. The mixed cultures were most effective in mineralizing organic phosphate and individually Bacillus sp. could be ranked next to mixed cultures.
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.
5463. Pumphrey, F.V. and P.E. Rasmussen. 1982. Winter wheat fertilization in the Northwest intermountain region.. OR Agr. Expt. Sta., Circular #691. OSU, Corvallis, OR..
Most dryland wheat needs 40-100 lb/ac N. Early spring applications of N are 50% more efficient. Most wheat fields also need S. Most soils do not need P, but if needed half as much P needs to be applied if drilled with seed versus seperate application. T: N fertilizer effect on yield. N and S in grain and straw of a 50 and 125 bushel crop. Yields of wheat fertilized with different sources and forms of N. Soil N in non-fertilized soil as influenced by soil depth and sampling from planting to harvest. Soil N as influenced by soil depth, time of sampling, and fertilizer applications.