NEWS for North Dakotans
Agriculture Communication, North Dakota State
University
7 Morrill Hall, Fargo, ND 58105-5665
April 30, 1998
In planning a successful crop rotation one of the most important things to consider is how one crop affects the next, says Duane R. Berglund, extension agronomist at North Dakota State University. Plotting the multitude of interlocking possibilities is a delicate, complex, and year-round task.
"Corn, for instance, does very well on soybean or dry bean ground most years," he says, "but is generally not affected by cereal crops—its yield is similar whether it follows small grain or follows corn. Corn does not respond to fallow nearly as well as small grains do, and generally it's only worthwhile putting it on fallow in a drought year."
Wheat should follow summer fallow, row crops, field peas or oats where possible, he says. Avoid continuous wheat or durum. Wheat performs best planted on fallow, next best after soybeans or field peas, then after dry beans, and then after sunflower. Wheat does better following oats than it does following any other coolseason cereal grain.
Oats apparently can go any place in the rotation except following oats.
Barley yields best on fallow, next best after row crops and poorest after barley. A common successful western North Dakota rotation is fallowwheatbarleysunflower. Barley also does well after flax when flax stubble is left to trap snow.
Flax should follow small grains. If seeded late, it should be followed by corn or fallow because of late season moisture utilization.
Rye uses a lot of moisture and needs to follow an earlyharvested crop or be planted on fallow. Due to problems with volunteers, rye should be followed by a row crop where grasses can be chemically controlled or controlled by latespring tillage. Rye should not be followed by winter wheat, spring wheat, barley or oats.
Sunflower and safflower are latematuring, drought-resistant crops which root deep and dry out the subsoil. They should follow small grains. In dry years, sunflower and safflower ground should be fallowed if soil moisture recharge is limited. Wheat and sunflowers complement each other in a crop rotation.
Dry edible beans can take the place of any row crop in the rotation. They should not follow sunflowers, canola or potatoes, due to shared diseases.
Soybeans should follow corn or small grains and be followed by the same.
Field pea, tame mustard and canola are earlymaturing crops and can be followed by many other crops. Wheat and barley are most often the grain of choice. Sunflowers and dry edible beans should be avoided due to shared diseases. Rotational restrictions may exist due to use of certain herbicides.
Green manure crops, including field peas, buckwheat, rye and sweet clover, have increased small grain and corn yields when moisture conditions are above average. Small grains or corn should follow an earlyplowed green manure fallow rather than a lateplowed green manure.
Perennial grasses and legumes generally should not be included in short rotations on good cropland. The exception may be on heavy clay soils where the soil needs improvement.
Berglund recommends the following steps for developing a successful crop rotation:
n Divide cropland into areas based on similarity of factors such as soil type, field topography, physical shape, distance from the farmstead.
n Classify the farm, field by field, with respect to cash crop potential into most desirable cropland, less desirable cropland and undesirable cropland.
n Plan specific rotations for each field. On the most desirable land, include the leading cash crops and the shortest, least flexible rotations. On the less desirable land, plan to put in longer and more permanent grasses as quickly as possible since continued cropping may not be profitable.
A new publication, "Crop Rotations for Increased Productivity," EB-48, is available at county offices of the NDSU Extension Service or may be ordered from the Extension Service Distribution Center at NDSU, telephone (701) 231-7882.
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Source: Duane Berglund (701) 231-8135
Editor: Barry Brissman (701) 231-7866