Source: University of Nebraska Extension
By Bruce Anderson, Extension Forage Specialist
Seedbed preparation is crucial for late summer plantings of alfalfa, grass, or some small-seeded cover crops. Half-hearted seedbed preparation will produce only a half-decent stand. Good seed-to-soil contact and weed control are essential.
Stubble from cereal crops like wheat makes a good seedbed. So can hailed-out soybeans. Hailed out corn may be a bit tougher, but many no-till drills can place seeds into this stubble soil very nicely, as long as there isn't excessive residue. Make sure you control weeds like foxtail, sunflowers, and volunteer grain before stubble seeding. Use herbicides like glyphosate or Gramoxone before planting to kill existing weeds.
Whenever planting in August be wary of grasshoppers. They love to eat new seedlings. Spray field margins with insecticides if more than 20 hoppers per square yard are present.
Remember, all these preparations are useless without moisture. Avoid planting into dry soil. If you have moisture, plant shallow for rapid emergence and early for seedlings to develop good cold tolerance. With help from Mother Nature, you'll be happy with the results.