Browse on keywords: fertility nitrogen Saskatchewan
Search results on 03/20/18
1015. Bowren, K.E. (ed.).. 1986. Soil improvement with legumes.. Saskatchewan Agriculture, Soils and Crops Branch.
This excellent publication summarizes research over the past 40 years pertaining to the use of legumes for soil improvement in Saskatchewan. The role of legumes in maintaining soil nitrogen was crucial prior to available fertilizer. But their value extends beyond their nitrogen contribution to the improvement of soil physical properties. One study found the tillage draft requirement to be up to one-third lower where legumes had been a regular part of the rotation. The positive effects of alfalfa were measured for over ten years in a series of wheat crops compared to plots with no alfalfa. Over 17 years, the average grain yield from a wheat-wheat/clover-clover green manure rotation with no fertilizer were 30% higher that a wheat-wheat-fallow rotation with fertilizer. Moisture depletion by legumes is the biggest hurdle to their use in very dry areas. Adequate fertility for the legumes is necessary to maximize their benefit. Use of selected Rhizobium strains can improve nitrogen fixation, especially on acid soils. Several varieties of sweetclover are mentioned with adaptation to forage or green manure use. The booklet has numerous color photos and many data tables and figures.
1396. Cook, F.D., F.G. Warder, and J.L. Doughty. 1957. Relationship of nitrate accumulation to yield response of wheat in some Saskatchewan soils.. Canadian J. Soil Sci. 37:84-88.
Good correlation between wheat yields and soil nitrate levels. Estimated that a significant yield increase from N fertilizers can be expected when the nitrate accumulation value is below 50 ppm N in soil from stubble fields or 40 ppm N in fallowed soils.
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.
2043. Fowler, D.B. and J. Brydon. 1989. No-till winter wheat production on the Canadian prairies: placement of urea and ammonium nitrate fertilizers.. Agron. J. 81:518-524.
A practical snow management system, which utilizes no-till seeding into standing stubble immediately after harvest, has permitted expansion of winter wheat production in western Canada. This study examined grain responses to urea and ammonium nitrate fertilizer banded and broadcast at seeding, or broadcast in the late fall or early spring. A moisture shortage biased the results. Fall banding prior to seeding helped reduce volatilization losses of urea (which were as much as 50%), but presented other problems and did not outperform broadcast ammonium nitrate.
9698. Nuttal, W.F., H.G. Zandstra and K.E. Bowren. 1970. Exchangeable ammonium- and nitrate-nitrogen related to yields of Conquest barely grown as second or third crop after fallow in NE Saskatchewan.. Can. J. Soil Science 51:371-377..
Exchangeable ammonium- plus nitrate-nitrogen measured to depth of 60 cm in 18 stubble fields during 1967, 1968 and 1969 in Black, Dark Gray and Gray Wooded soils of northeastern Saskatchewan was inversely related by regression analyses to yield increases of Conquest barely. The mean protein content of the grain was significantly related by regression to nitrogen soil tests. Increased yield from nitrogen fertilization resulted in a decrease in phosphorus content of the grain.