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4. Soil Management Considerations
Principles of Crop Rotation
1.
Rotate legume with non-legume crops.
•
Cereal crops, such as wheat, corn, and sorghum, need a lot of nitrogen. Legumes fix
nitrogen and thus supplement nitrogen for the following cereal crop.
2.
Rotate exhaustive crops with less exhaustive crops.
•
Crops that need a lot of nutrients, such as corn and wheat, are called “exhaustive crops”
because cultivating them continuously depletes soil fertility or soil nutrient status.
•
Crops that can grow well even without a lot of nutrients are less exhaustive, for example
legumes and brassicas (mustards, radish).
•
Cultivation of exhaustive crops in rotation with less exhaustive crops helps restore soil
fertility and thus to sustain crop production.
3.
Rotate fibrous root crops with tap-root crops for best nutrient utilization.
4.
For erodible areas, crops useful for stabilizing soils should be considered, for example barley,
cereal rye, sorghum-sudan, and cowpea.
5.
Under dryland and limited water conditions, select drought resistant crops, such as guar,
lentils, or tepary beans.
6.
Crop rotations should be adapted to local soil and environmental conditions.
7.
Crops should be evaluated for high market value and profitability.
Deep rooted
•
Alfalfa
•
Sunflower
•
Safflower
Medium rooted
•
Barley
•
Wheat
•
Canola
•
Corn
•
Sorghum
Shallow rooted
•
Pea
•
Lentil
•
Guar
•
Tepary Beans