Corn is a major field crop in New York State with more than 1 million acres planted annually. Typically, grain corn (including dry-shelled and high-moisture) represents 55% of the acreage, whereas corn silage represents the remaining 45% of the acreage. Recently, corn has been a very profitable crop to grow because of relatively high yields as well as high prices received by farmers. Although corn is a very profitable crop on NY farms, it is also an expensive crop to produce. The high costs of seed, fertilizers, and chemicals require a high degree of crop management to obtain top yields and economic returns. Corn producers must also carefully manage the crop to insure a high quality crop. Corn producers must select the correct hybrid relative maturity in relation to the growing region and planting date to insure a grain crop with high test weight (>55 lbs./bushel) and relatively low grain moisture (22% or less) at harvest, which saves on drying costs. Dairy producers must select the correct hybrid relative maturity in relation to the growing region and planting date to insure a silage crop in the 65-68% moisture range (32-35% dry matter content) at harvest in September, which should result in starch concentrations close to 35% and fiber digestibility at 60% or more.
Growers should produce corn on moderately well drained to well-drained soils. When corn is grown on poorly drained soils, corn can drown out during wet May conditions or show yellowing and reduced growth and delayed development during wet June conditions. Furthermore, if N is applied before or at planting, much of the N will denitrify and escape into the atmosphere during wet spring conditions on these poorly drained soils. On excessively drained soils, much of the N applied before or at planting, will leach and escape into the water table during wet spring conditions. Furthermore, excessively drained soils typically dry out in July and August, resulting in low corn yields because of poor kernel set and/or poor kernel-fill during dry growing seasons.
Cash crop producers in NY typically grow corn in a corn-soybean rotation or corn-soybean-wheat/red clover rotation. Rotated corn yields 5-15% greater following soybean or wheat/red clover compared to a continuous corn crop. In addition, rotated compared with continuous corn can avoid some pest problems, such as corn rootworm, and requires 20-40 fewer lbs/acre of N when following soybean and 40-60 fewer lbs/acre of N when following wheat/red clover. Consequently, most cash crop producers strive to rotate corn to reap the 5-15% yield benefit while reducing inputs for pest management and N fertilization. Prices for these crops, however, may skew the rotation(s) in favor of the crop in the highest demand by grain traders.
Corn is typically grown in a 3-year continuous corn-3 year perennial forage rotation on dairy farms. Although 2nd and 3rd year corn on a dairy farm no longer reaps the yield benefit of rotated corn, N from the previous perennial forage crop continues to be released, albeit less each year, allowing dairy producers to apply less manure or N fertilizer to 2nd and 3rd year corn. Some dairy producers may substitute oats or spring barley for second year corn to reap the yield benefit of rotated corn in the 3rd year of the phase before rotating back to perennial forages.