Browse on keywords: crop rotation fallow
Search results on 05/24/13
3098. Swanson, Guy. 1990. Annual production of spring wheat in Montana and the Columbia Basin. Bumper Times special edition, Jan. 31, 1990; p. 6; S. 4305 University Rd., Spokane, WA 99206.
Minimum till continuous spring wheat produced the highest net returns in a Montana study. The cost of Roundup reduced net returns in no-till, although no-till had the highest gross returns. John Rae, a WA farmer, has compared continuous no-till spring wheat with his normal winter wheat-fallow system. The continuous system has produced $350/ac more gross returns over five years in his 9" rainfall area.
5585. Ramig, R.E. and L.G. Ekin. 1987. Fallow systems for semiarid eastern Oregon and Washington.. OR Agr. Expt. Sta. Special Report 797, p.34.
5601. Ramig, R.E. and L.G. Ekin. 1988. Should I double fallow?. OR Agr. Expt. Sta. Special Report 827, p.57.
5954. Rosell, R.A., R. Martinez, K. Sommer and R. Miranda. 1982. Relationship of crop rotation and nitrogen availability for wheat in semiarid Argentina.. Plant Nutrition 2:551.
A sequence of small grains, annual natural pasture with grazing and a short (3 months) summer-fall fallowing showed low productivity when compared with a sequence of continuous grain with a long (6 months) fallowing. Wheat yields, number of ears per surface area and total nitrogen uptake were two times higher with long fallowing. Fertilizers are rarely used. Long-term average yields are in the order of 1.2 tons per hectare.
6329. Slinkard, A., V. Biederbeck, L. Bailey, P. Olson, W. Rice, and L. Townley-Smith. 1987. Annual legumes as a fallow substitute in the northern Great Plains of Canada.. IN: J.F. Power (ed.). The role of legumes in conservation tillage systems. p. 6-7..
Tested tangier flatpea, indianhead lentil, fababean, field pea, and Austrain winter pea at several locations. Data suggest that annual legume green manures contributed about 40 lb N/ac, and increased wheat yields more than the addition of 54 lb N fertilizer on wheat stubble. Moisture greatly affected yield after legumes. Choice of annual legume depends on relative seed cost. Suggest indianhead lentil as most promising species. The value of the N it fixes comes close to the seed cost. Three management systems are proposed.
7816. Ford, G.L. and J.L. Krall. 1979. The history of summer fallow in Montana.. Montana Agr. Expt. Sta. Bull. 704.
This excellent publication describes the historical development of summer fallow use in dry farming in Montana and some of its consequences. Data from 1974 indicate that aboaut one-third of the cropland in the state was in summer fallow (5 million acres). In Montana, the fallow period is 14 and 21 months for winter and spring grain respectively. Results from the early 1900's indicated more profitable returns from alternate crop-fallow compared to continuous cropping. This was due to both more moisture and available nitrogen built up under fallow. Summer fallow was not widely adopted until the 1920's, when a series of very unfavorable weather years occurred and showed the risk reduction value of fallow. Serious wind erosion became a problem at that time and led to the introduction and widespread adoption of narrow alternate crop-fallow strips perpendicular to the wind direction. Fallow led to a greater decrease in soil organic matter and total nitrogen (40 and 35 % decrease) than with continuous cropping (35 and 27 % decrease). Further research found that continuous cropping made more efficient use of moisture than fallow. As nitrogen fertilizer and herbicides became available, fallow was no longer as important for these aspects. Summer fallow has also caused the development of saline seep conditions on hundreds of thousands of acres. This condition occurs where summer fallow stores more moisture than a crop uses, and the water then moves deeper in the soil profile until it hits a confining layer, causing it to move laterally with dissolved salts, and to break out as a seep further downslope. In one watershed, the percentage of total land area affected by saline seep increase from 0.1% to 19% over 30 years. Continuous cropping and use of deep-rooted plants such as alfalfa can help solve this problem. The authors propose a new approach to cropping intensity, one called "flex-cropping" in which the decision to plant a crop is based on the presence of at least 3 inches of stored soil water at seeding time. This system would reduce some of the negative effects of summer fallow while also reducing exposure to drought risk. Federal acreage restrictions under the commodity programs pose a major barrier to this approach.
7907. Sims, J.R.. 1988. Dryland legume-cereal rotations for the Northern Great Plains-Intermountain region. p. 17-19. IN: S.K. Hilander (ed.). Proc. AERO/MSU Soil Building Cropping Systems Conference, Dec. 1988.
7930. Sims, J.R.. 1988. Research on dryland legume-cereal rotations in Montana.. Symposium on Crop Diversification in Sustainable Agriculture. Univ. of Saskatchewan, Saskatoon.
This paper opens with a review of the long-term findings of historic rotation studies for dry farming in Montana and concludes that improved varieties and management abilities call for a re-examination of alternatives to the crop-fallow system. A short description of ley farming in Australia follows, and then research on adapting it to Montana conditions is presented. Results to date indicate the potential for both grain and forage legumes to successfully precede a cereal crop without significant cereal yield losses, and with a reduced need for nitrogen fertilizer. T: medic soil water use and N contribution; wheat yields after medics; pulse and cereal grain yields; annual legume forage yields; fertilizer response curves for barley with various forecrops.
8374. Peterson, G.A., E. McGee, D.G. Westfall, C.W. Wood, and L. Sherrod. 1990. Crop and soil management in dryland agroecosystems.. Technical Bull. TB90-1, Dept. of Agronomy, Colorado St. Univ., Fort Collins, CO.
A large-scale field experiment was established in 1985 at 3 eastern CO locations to examine alternatives to the traditional wheat-fallow cropping system. All new treatments used no-till instead of tillage intensive management. Rotations include wheat-fallow, wheat-corn-fallow, wheat-corn-millet-fallow, and perennial grass. After five years, the more intensive cropping was giving greater grain output, nitrogen use efficiency, and water use efficiency than the wheat-fallow system. Organic matter levels also appear to be increasing. The research is also examining each strip plot at three landscape positions: toeslope, sideslope, and summit.
8697. Kresge, D.O. and A.D. Halvorson. 1982. FLEXCROP: a dryland cropping system model.. USDA-ARS Agric. Prod. Res. Rept. 180.