Many would consider 'early planting' of corn to land on or about April 20 to 27, depending on your area of Ontario. Most of us are aware that planting in this early time frame has both benefits and pitfalls to corn production. So, what management factors do growers need to consider to A) maximize yield potential, and B) minimize production risks associated with early planting?
1) How long do you go? Many full-season hybrids are positioned assuming a late April planting opportunity. What about trading up to longer maturities? Generally, growers should realize that they are gaining CHU accumulation on the end of the growing season, not the beginning. A typical late September/early October week - assuming the absence of a killing frost - would accumulate 75 - 125 CHU. The proper recommendation based on this knowledge is to trade up at least some of your long-day hybrids by 100 CHU. As always, ensure that the new hybrid possesses the necessary characteristics of early season spring vigour, and early flowering. There is no question that maximizing CHU selection will maximize yield potential.
2) Know Your Soils. Growers know their soil best. Clay-based soil often works best the first time it is dry - but if cold, wet weather follows, these soils can turn to anything but a growing medium very quickly! Many fields have been worked the first time, and warm rain will condition these soils dramatically, making for a great seedbed.
3) Start Clean. Warm spring rains and sun bring on the weed growth in many fields. To prevent insect infestations, and to assist in soil warming, start with a clean field - either by tillage or pesticides. In the new age of cheap generic glyphosate, there's no excuse not to start clean.
4) What About Insects? There are 3 main insects of concern given present weather conditions and the time of year.
a. Millipedes are a persistent pest of early planted corn. Mitigating factors are high soil organic matter or the presence of decaying organic matter (residue and manure), and cool, wet conditions after planting. Millipedes feed on decaying organic matter particles, and move into the upper soil profile (the seed zone) during cooler spring temperatures. The germinating seed is an attractive food source for this pest, and there is no soil-applied or seed-applied insecticide that controls millipedes. When warm temperatures return, the millipedes are driven down out of the seed zone to cooler soils. Control options include residue management, use of row cleaners, and any tillage that warms the soil.
b. Black Cutworm is a sporadic but very problematic corn pest in Ontario, particularly the Lake Erie and Lake St. Clair northern shores where sandy soils are present. Warm April south winds blow adult cutworm moths over the lakes, where they seek refuge in new, lush spring plant growth. In sandy soils, they lay their eggs in the plant growth and the larvae (worms) burrow into the soil once hatched, and emerge at night to feed on the corn seedling. In these areas, it's critical for growers to control spring weed growth, preferably by tillage or a fast-acting burndown. Chickweed species are a favorite haven for cutworm moths.
c. European Chafer & white grubs can be a problem in early, warm spring conditions, where grass species were or are present in the field prior to or after corn planting. Field areas adjacent to grass crops can also be very problematic. These pests are most active in warmer weather, in contrast to millipedes. Again, any mechanical activity to disturb the soil and bring grubs to the surface is beneficial, where the elements and predation by birds, skunks, and raccoons can offer some control.
These are three common early-season pests. While chemical control options are limited, corn producers do have other options to consider. Remember that often, the best way to beat a corn pest is to provide the seedling with ample opportunity to grow faster than the pest can fatally feed on it. In other words, outgrow the feeding pressure. Growers can do this by planting into warm soils, using aggressive starter blends in problem fields, and eliminating weed competition from the start.
5) Spread Your Risk. The golden rule of crop production, this could mean switching only a few acres to longer-day hybrids. It could also mean planting only a percentage e.g. <50% of your intended corn acres during the first available planting window, particularly if cooler, wetter conditions are forecast. And perhaps most importantly, how many acres get 'forced in' to marginal seedbeds with the threat of rain in the forecast? The answer: too many! The first drink of water (first six to 12 hours) for any seed is critical. If cold rain is forecast, growers may be best to keep the planter in the shed for the day prior. There will be other, better days to plant. Remember that patience always pays when it comes to planting and establishing a good crop.
An earlier-than-normal start to corn planting in Ontario offers growers a tremendous opportunity for increased production success. To determine the merits and management considerations, please contact your PRIDE Seeds Dealer or your local PRIDE Seeds Regional Manager or Agronomist.
