Browse on keywords: crop rotation soil quality
Search results on 12/18/18
4058. Mann, F.. 1920. Frank Mann's soil book.. Prairie Farmer, Chicago, 180p..
A detailed description of sustainable soil management on an Illinois farm.
978. Bolton, H., L.F. Elliott, R.I. Papendick and D.F. Bezdicek. 1985. Soil microbial biomass and selected soil enzyme activities: effect of fertilization and cropping practices.. Soil Biol. Biochem., 17:297-302.
The microbial properties of two adjacent fields were compared, one being under organic management, the other conventional management. Microbial indices tended to be more favorable on the organic field, with higher microbial biomass and enzyme activities.
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.
1854. Emmond, G.S.. 1971. Effect of rotations, tillage treatment and fertilizers on the aggregation of a clay soil.. Canadian J. Soil Science, 51:235-241.
Soil aggregation was lowest in a wheat-fallow rotation and increased in other fallow-grain rotations with the second, third and forth crops after the fallow year. The best aggregation was under continuous wheat. Rotations containing hay crops increased aggregation significantly. Tillage treatments affected soil aggregation in the following order: green manure crop plowed under> cultivated with trash cover> crop residue plowed under > cultivated with crop residue burned off = crop residue disked in. Fertilizer (11-48-0) increased aggregation except where crop residue had been removed. Barn manure increased soil aggregation. T: Effect of barn manure and crop sequence on soil aggregation. Effect of 5 tillage treatments on soil aggregation.
2211. Goldstein, Walter. 1989. Thoughts on drought-proofing your farm: a biodynamic approach. Working paper No. 2, Michael Fields Agr. Institute.
Describes the influence of soil aggregate size on moisture retention and crop growth. Discusses the benefits of perennial grasses in the rotation to improve soil structure. Discusses management of sweetclover for grazing and green manure. Discusses stubble mulch tillage.
2406. Hanley, Paul (ed.). 1980. Earthcare: Ecological agriculture in Saskatchewan.. Earthcare Information Centre.
A well-written text covering all aspects of biological farming in the prairie region of Saskatchewan. Practices apply to small and large farms. Includes reports from selected farms. References at the end of chapters.
2784. Hulbert, H.W.. 1927. Sweetclover.. ID Agr. Expt. Sta. Bull. #147.
Biennial white is best forage, biennial yellow is too short; can handle alkaline soils; earlier seeding is best; 15 lb/ac seed, or 10 lb/ac in drier areas; nurse crop is risky, peas may be best; 3/4 T/ac hay first season, 2-3 T/ac second year; best used for pasture and soil improvement; can be grazed early spring through fall; improves soil quality, breaks up subsoil; sweetclover as green manure too expensive for dry areas; one system used is WW/SC planted in fall (unscarified seed) at 5 lb/ac; after wheat harvest, pastured SC into late fall; field is spring plowed and SF; then WW again, this raised WW yields 3-8 bu/ac; might try with Hubam (annual) SC.
3107. Dormaar, J.F. and C.W. Lindwall. 1989. Chemical differences in dark brown chernozemic Ap horizons under various conservation tillage systems.. Can. J. Soil Sci. 69:481-488.
Soil properties were investigated in two long-term studies: a 19 yr study of till vs. no-till in wheat fallow, and a 9 yr study of till vs. no-till with 3 rotations, including continuous cropping. No-till had the predominant influence on improving various soil physical and microbial properties. There was little difference in continuous cropping versus wheat-fallow, with tillage. The study compared soil from the entire plow depth, and concluded that 19 yr was long enough for the entire Ap horizon to benefit from no-till. No-till in both studies led to 40% of the dry aggregates being >0.84 mm. Dehydrogenase and phosphatase activities were twice as high under no-till as under cultivatiion. No-till also led to the largest monosaccharide accumulation in the soil.
4377. McKay, H.C. and W.A. Moss. 1949. High protein wheat with conservation farming.. U. of Idaho Extension Bull. #181.
Emphasize need for legume - grass rotation to maintain soil productivity. Suggest a 7 yr sweet clover rotation or a 9 yr alfalfa rotation. Yellow sweet clover plus mountain bromegrass or slender wheatgrass; Ladak alfalfa plus smooth brome and big bluegrass (high rainfall) or crested wheatgrass (low rainfall); early spring seeding recommended without nurse crop; methods of establishment, plow sweetclover at 12-22" height; use sweetclover as a surface mulch to prevent erosion. T: soil moisture and sweetclover growth; wheat after sweetclover; yield and protein.
4807. Nelson, A.L.. 1950. Methods of tillage for winter wheat.. WY Agr. Expt. Sta. Bulletin 300.
Fallow/winter wheat production decreased soil N by 33% in the top 6" over 35 years. Continuous cropping lost 24% of the soil N. Crop rotations using green manure every 4th year did not decrease the loss of soil N. Average winter wheat yields (bu/ac) over 34 years for 3 rotations were: oats/rye(GM)/winter wheat/corn - 12.9; oats/peas(GM)/winter wheat/corn - 12.7; fallow/winter wheat - 13.7; oats/corn/winter wheat/rye - 13.2; oats/corn/winter wheat/peas - 14.1; oats/corn/winter wheat/fallow - 13.2. It was observed that green manure took years to break down. Tillage with an eccentric one-way increased winter wheat yields 2 bu/ac over 10 years compared to plowing. The eccentric one-way conserved moisture. Continuous cropping resulted in winter wheat yields 55% of biennial yields following fallow. Soil moisture was 3-4% lower in October after continuous cropping versus fallow.