Browse on keywords: tillage dryland
Search results on 12/10/13
754. Bennett, W., D. Pittman, D. Tingey, D. McAllister, H. Peterson, and I. Sampson. 1954. Fifty years of dry land research (at the Nephi Field Station).. Utah Agr. Expt. Sta. Bulletin 371.
Summarizes the results of 50 yr of research at the Nephi Field Station in cental Utah. Discusses climate - spring rainfall crucial, fall emergence of wheat correlated to high yields. Ave. annual precipitation is 12.65 in. Tillage experiments - fall verus spring plowing did not affect yields, while late spring plowing lowered yields. Plowing to 8" depth increased yields by 8% compared to plowing at 5". Yields were higher with plowing and no further cultivation on fallow (weeds controlled) than with normal fallow tillage. Yields were poor with stubble mulch. Fertility: A pea green manure increased wheat yields both in the short and long term. Wheat yields were sometimes depressed by green manure, due to moisture shortage or N immobilization. Manure application increased wheat yields in all treatments, and was more beneficial in wet years. N fertilizer increased wheat yields and protein. Burning straw increased yields for 30 yr, then they began to decline. No response to P. Wheat-fallow gave the greatest yields and net returns, and wheat was the only crop distinctly benefitted by summerfallow. Alfalfa depressed the following wheat yields but improved soil fertility. Continuous wheat yielded less than 40% of wheat-fallow. Wheatgrasses showed potential for forage and seed. Spring wheats yielded 60% of winter wheat. Only 32% of rainfall was stored as soil moisture in summerfallow. Overall, yields were low (15-25 bu/ac) and treatment differences were small (1-3 bu). These results predate the semidwarf wheat varieties.
5335. Poole, M.L.. 1987. Tillage practices for crop production in winter rainfall areas. p. 24-27.. IN: P.S. Cornish and J.E. Pratley (eds.) Tillage - New Directions in Australian Agriculture..
5622. Ramig, R.E., R.R. Allmaras and R.I. Papendick. 1983. Water conservation: Pacific Northwest. p. 105-124.. IN: H.E. Dregne and H.O. Willis (eds.). Dryland Agriculture. ASA Monograph 23..
Descriptions of tillage and summer fallow practices in 200-400 mm/yr precip. zones. Covers: fall, spring, summer tillages for summer fallow; weed control; time of planting. Also descriptions of conservation tillage practices in fallow such as stubble mulching, chemical fallow. Annual cropping is included and sections cover moldboard plowing, fall chiseling, cloddy seedbeds, no-till, slot mulching. T: precipitation and soil water storage for 3 tillages. Soil water evaporation rates.
6929. Unger, P.W., C.W. Lindwall, D.W. Anderson, and C.A. Campbell. 1989. Mechanized farming systems for sustaining crop production and maintaining soil quality in semiarid regions.. unpublished manuscript, USDA-ARS, Conservation and Production Research Lab, Bushland, TX 79012.
This review paper presents research results primarily from the Northern Plains, Southern Plains, Pacific Northwest, and Australia, addressing issues of soil quality and organic matter, erosion, water storage and utilization, and how these are affected by tillage choices, crop rotations, and other management aspects. Cultivation of semiarid soils generally leads to soil organic matter (SOM) losses of 40-60%, with most loss in the first 20 years. The active fraction of SOM will change faster than the total SOM. The fraction of N that is readily mineralizable decreased more quickly than total N, indicating a reduction in the nutrient-supplying power of the soil over time. Cultivation decreases the proportion of soil aggregates >1 mm. Dry-stable aggregates >0.84 mm are needed to prevent wind erosion. In the Northern Plains, about 60% of the precipitation falls in the May to August growing season. The crop-fallow system here is relatively inefficient at water storage, storing only 20-25% of the precipitation during the fallow period. Crop stubble is crucial to snow trapping and moisture retention. Alternating strips about 5 m. wide of tall and short stubble increased snow depth and density and resulted in 30% more water storage compared to a uniform medium-height stubble. No-till improved yields in many cases by increasing stored moisture, but suitable herbicides are necessary for weed control. Flex cropping in Montana was the most efficient system for using moisture. In the Central Plains, increased evapotranspiration makes ample surface residue very effective. Yields for wheat in a fallow system were more than double those for continuous wheat, making the fallow system more economic. In the Pacific Northwest, major losses result from runoff and from evaporation, due to capillary action in undisturbed surface soils. Water storage efficiencies were 50-75% during the first winter, and 10-50% during the second winter at Pendleton, OR. Surface residues resulted in greater evaporative losses during the summer. To control erosion, innovations such as the slot mulch system, the paraplow, and basin pitters (dammer-diker) have been used. The paper has an excellent list of references on dryland cropping.
9284. Bracken, A.F. and G. Stewart. 1930. A quarter century of dry farm eExperiments at Nephi, Utah.. Utah Agr. Expt. Sta. Bulletin 222, Logan, UT..
Dry farming began in Boxelder County in 1863 and has now extended to all parts of the state where precipitation and topography permit favorable development. Alternate cropping with fall or early spring planting is the general practice. On page 41, there is a summary of results covering the following subjects: weather, data, treatment of land before plowing, plowing, treatment of summer fallow seeding experiments, cropping experiments, cereal varieties, fertility experiments, and rotations.
9402. Henderson, D.W.. 1979. Soil management in semiarid environments. p. 252-307.. IN: Agriculture in SemiArid Environments. Ecological Studies Volume No. 34, Springer-Verlag Publ.,.
To assess the impact of soil management in a meaningful way and in terms that can be applied in a variety of situations is nearly impossible with existing information. There are strong limitations to the impact of tillage and other soil management practices on crop production, especially under semiarid and arid conditions. Semiarid agriculture, limited as it is by water, economically cannot support intensive or costly practices. Relatively sparse growth frequently provides minimal levels of crop residue to be utilized in various ways. Economic tillage operations generally are relatively shallow, especially in developing areas with little mechanization, and therefore affect only a very small portion of the total root zone depth.
9962. Chilcott, E.C.. 1910. A study of cultivation methods and crop rotations for the Great Plains area.. USDA Bureau of Plant Industry, Bulletin 187. 78 pp..
This paper reports the results of a four-year experiment in crop rotation and cultivation methods conducted at eleven stations in the Great Plains area. Some of the questions asked of this experiment were how can the largest average yields of corn, spring wheat, oats and barley be obtained, do moisture conservation methods pay where continuous cropping to the same crop is practiced, and can green manuring be profitably substituted for summer tillage? The results found that a 3-year rotation of corn, wheat and oats gave the most profitable returns. Continous cropping with moisture conservation methods of fall plowing and fall, winter and spring tillage did not give results to warrant its recommendation. The most highly recommended practice was that of green manuring. For greatest benefits to the soil, it was recommended to plow in a green manure crop in early season, with little summer tillage, until wheat planting time.