Cover Crops and Conservation Tillage
for Soil Erosion Control on Cropland
Establishing in corn - Establishing Birdsfoot Trefoil or Crownvetch as a Living Mulch
Crownvetch and birdsfoot trefoil seedling survival is probably best in corn because corn does not produce as dense a shade as soybeans or small grains. Corn may be planted conventionally or minimum- or no-till. The herbicide choice, however, is rather limited (see Table 2).
At the moment, the safest and probably the best method of establishment is to use Pursuit with Imidazolinone-Tolerant (IT or Clearfield) corn hybrids. Pursuit-resistant corn hybrids now are readily available in almost all maturities. Birdsfoot trefoil and crownvetch seedlings are more tolerant to Pursuit after emergence and Pursuit is most active when applied to the weeds early postemergence. Choose one of the recommended herbicide programs from Table 2.
Pursuit is weak on common ragweed, common lambsquarters and most annual grasses except the foxtails. Basis or Permit may be tank mixed with Pursuit to improve the weed control or a cleanup treatment of Accent, Basis or Permit may be applied postemergence to the corn. Permit may be used the year of seeding or anytime thereafter for common ragweed and yellow nutsedge control. All of these herbicides are known to be safe on both crownvetch and birdsfoot trefoil seedlings.
Upright-leafed varieties of corn that permit greater light penetration or corn harvested for silage allow crownvetch seedlings to build up more energy reserves for winter survival than if corn is allowed to go for grain. Harvesting corn for grain is not discouraged however.
Corn, soybeans, small grains, or forages may follow in rotation. See First-Year Rotations, below, for weed control recommendations and tillage practices.