Browse on keywords: crop rotation moisture fertility
Search results on 07/21/18
1180. Campbell, C.A., R.P. Zentner and P.J. Johnson. 1988. Effect of crop rotation and fertilization on the quantitative relationship between spring wheat yields, available soil moisture, and precipitation.. Canadian J. Soil Sci., 68(1):1-16.
The effects of crop rotation and fertilization on the quantitative relationship between spring wheat yields, available soil moisture, and growing season precipitation were determined. Stubble-seeded wheat required 68 mm of moisture to produce the first kilogram per hectare of grain; fallow-seeded wheat required about 46mm. The lower threshold level of MU for grain production decreased from about 140mm to the values cited above; this has resulted in substantially greater moisture use efficiency in recent years likely due to better, more timely crop mangement and the improved cereal varieties.
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.
7850. Koala, S.. 1982. Adaptation of Australian ley farming to Montana dryland cereal production.. M.S. Thesis, Dept. of Plant and Soil Sci., Montana St. Univ., Bozeman, MT 59717.
This study examined the potential to adapt the ley farming system used in Australia to dryland cereal production in Montana. The ley system alternates a grain crop with a self-seeding forage legume. The legumes tested in this study included 5 Australian medics, 7 subclovers, 2 lupins, fababean, and a native Montana black medic. One full cycle of the system was completed. All grain yields (spring wheat) were higher after the legumes than after fallow. Soil water to 120 cm was similar in all plots at wheat planting. The black medic treatment had the highest water use efficiency (100 kg grain/cm) and fallow the lowest (55 kg grain/cm). There were higher levels of soil nitrate after the legumes than after fallow. Re-establishment of the legumes after wheat ranged from 3 to 93% ground cover, with black medic being the highest. Overall, black medic from Montana performed best in this study.