Increased management considerations for corn-on-corn
Demand for corn remains strong causing some growers to consider including more corn in their crop rotation. For many, that means more corn-after-corn production, notes DuPont Pioneer.
But the seed company also warns that yield is generally lower in corn after corn. Yield reductions of 15-30 bushels per acre are not uncommon in corn after corn compared to corn after soybeans.
This yield reduction can be due to several factors, many of which can potentially be mitigated by careful agronomic management. That management is what has to be addressed, which means spending more time planning and executing in-field programs.
A corn grower has to consider dealing with all the factors that can reduce corn after corn yields, and a crop consultant or ag retailer’s agronomist can be helpful in assisting grower with their management plan.
Some challenges to overcome by stage of growth and early to late in the growing season are specific to corn after corn production.
Early-season challenges are:
Heavy corn residue
Soil temp 5-10 degrees cooler
Nitrogen tie-up when surface applied
Slow corn growth
Increased insect pressure
Mid- and late-season challenges:
High disease inoculum levels, leading to increased leaf, stalk, and ear disease
Nitrogen (N) deficiency
One of the points noted by DuPont Pioneer agronomists is that as tillage intensity decreases, rotation becomes more beneficial.
A grower should avoid surface N applications in growing corn on corn ground because corn residue will tie up N as it decomposes. The DuPont Pioneer agronomists’ recommendation is to band N seven to eight inches deep and consider using starter fertilizer that contains N. Selecting highly productive soils, will increase the chance for success with corn after corn production, it is suggested.
As for disease management, the seed company agronomists suggest planting diverse genetic hybrids with good disease resistance. At the tassel stage, strong consideration should be for a foliar fungicide application.
Insect pest management tips include planting a Bt hybrid with resistance to pests, both above ground and below ground pests; use a high-rate seed insecticide treatment; also, consider using in-furrow insecticides; and scout for using foliar insecticides when needed.
Good management can mean really good yields with corn after corn, but to repeat the point, good management is the key.