Richard Taylor, Extension Agronomist; rtaylor@udel.edu
With the higher prices available for corn, it would seem that profitable corn production is assured. However even if a profitable season is highly likely where either irrigation or timely rainfall is plentiful, there are many agronomic practices that can be used to improve the chances of success. The first one that comes to mind relates to the yield curve as affected by planting date. In research conducted in Delaware and surrounding states in the past, we’ve seen slightly (3 to 5 percent) lower yields when corn is planted before the first of May. Large acreage growers often feel the need to begin planting early just to be able to finish planting their corn acreage before yields begin to decline due to late planting. Small acreage growers can get restless seeing others out planting corn and move to plant before the ideal window, the last week of April and the first week of May. Growers can still satisfy the need to plant enough acres to finish in time or the urge to get into the field early by dividing their fields up into high yield potential fields, moderate yield potential fields, and low yield potential fields. Plant the low yield potential fields at the earliest opportunity and again at the end of the corn planting window if all of the acres aren’t completed early or if special soil conditions preclude entering the field until later in the spring. If all the low yield potential fields are planted and more time is available before the ideal planting window, growers should move to the medium yield potential fields. As soon as the ideal window opens, growers should change to the best high yield potential fields. The higher yield potential during this period can add quite a bit of extra corn to your final farm yield. Once past the first week of May or once all the best fields are planted, move on to finish with the medium yield potential fields and finally those low yield potential fields with special problems are that weren’t planted earlier.
On no-till fields, be sure to use row sweeps or row cleaners to help warm up the soil at the planted rows. Soil temperatures high enough for rapid uniform germination are essential in obtaining the highest possible yield potential. Also, consider using hybrids ranked highest for cold tolerance since improvements have been made on that front in the past few years.
The same thing applies to deciding where to apply the most fertilizer dollars. You should always aim at fertilizing your high yield potential fields with enough fertilizer to obtain maximum economic yields (MEY). Recognizing that yield from your medium yield potential fields will be lower than that in the high potential fields, you should reduce your input levels on these fields. For the low yield potential fields, keep the number of fertilizer dollars spent on these fields to the minimum needed to obtain the average yield you expect off these fields. By adjusting your fertilizer rates for each field, you can reduce your overall fertilizer bill as well as ensure that your get the biggest bang for your buck from your best fields.
I think it is safe to say that seed costs are higher than ever nowadays. Again, choose the best hybrids and use the highest (best) seeding rate on your best fields. Not only will you get more for your money but since you’ll be planting this expensive seed at the ideal time, your plant stands will be better and less seed will be wasted. In other words, use your race horse hybrids on your better fields. For the medium and low yield potential fields, choose the work horse hybrids which can tolerate the less favorable growing conditions and still respond if the growing season turns out to be a good one. Adjust your seeding rate slightly up when planting early to help ensure better stands and lower your seeding rate later in the planting window when the soil is warmer and germination conditions are closer to ideal. In addition, you won’t waste as much seed in fields that have lower potential.
A final suggestion on irrigated land would be to consider irrigating early if the dry conditions persist. A recent visit down the state showed very low water levels and therefore water tables in much of central and southern Delaware. Although corn uses very little water when it is early in its growth cycle, it is highly likely that the subsoil layers are not at field capacity. It is highly advisable to bring soil moisture levels in both the top soil and subsoil close to their maximum water holding capacity early in the season so that the corn will not suffer early water stress. This also will give you a base or buffer so that later in the season during tassel, silking, and seed fill, the irrigation system can keep up better with the crop’s water demand.