Browse on keywords: fertility pH
Search results on 05/20/13
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
2862. Hurd-Karrer, A.M.. 1946. Relation of soil reaction to toxicity and persistence of some herbicides in greenhouse plots. USDA Technical Bulletin 911.
Deals with herbicides used prior to 2,4-D, such as sodium chlorate, sodium thiocyanate, ammonium sulfamate, borax. Initially, all herbicides were most toxic in acid soils, and least toxic in alkaline soils, and persisitence was similar. Borax was the most persistent. Nitrogen fertilizer did not reduce chlorate toxicity in a practical manner.
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.
3945. Mahler, R.L.. 1981. Implications of acidification of farmland in northern Idaho.. ID Agr. Expt. Sta. CIS #629.
Loss of Ca and Mg is primarily by crop removal in northern Idaho; wheat crop removes 20-50 lb/ac/yr of each cation; ammonium-based fertilizers have been main acidifying factor; had been a big change in past 25 yrs; large % of soils now below pH 6.0; current wheat varieties in Idaho acid intolerant; soil acidity may favor certain weeds and diseases.
3992. Mahler, R.L. and R.E. McDole. 1987. The relationship of soil pH and crop yields in northern Idaho.. ID Agr. Expt. Sta. CIS #811.
In 1984, only 6% of farm soils had pH>6.4; pH drops 0.1 unit for every 2 winter wheat crops; minimum pH levels for crops: alfalfa = 5.7, barley = 5.3, bluegrass = 5.2, lentils = 5.6, peas = 5.5, wheat = 5.2 (variety dependent); bluegrass seed may be the most acid tolerant crop now grown; almost half of pea and lentil ground is too acid for maximum yield; crop yield loss due to acidity needs to exceed 20% to be economical to correct. T: soil pH versus yield for various crops.