Selection of your wheat variety is the first step for increasing your double-crop soybean yield. It all begins with selecting ultra-early and early-maturity varieties that have proven yield, high test weight and resistant to Fusarium head blight.
Limagrain Cereal Seed’s (LCS) selection for ultra-early varieties has given many farmers both the opportunity to grow high-yielding wheat followed by high-yielding soybeans. The harvest of ultra-early wheat varieties at 18% moisture can increase soybean yields dramatically since soybeans can be planted sooner. This also improves the odds for a timely rain on the newly planted double-crop soybeans, assisting rapid emergence and creating a more uniform stand and rapidly growing soybean plant.
Limagrain Cereal Seeds developed the ultra-early wheat varieties to allow double-crop farming practices to move further north in Illinois. Reports on LCS 1171 grown near Pontiac, Illinois, in 2015 had wheat yield of over 110 bu/A at 59 lb. test weight and very low DON levels. Dave Stipp, who farms at Blackstone, Illinois, regularly harvests straw for additional profit per acre profit, and his double-crop soybeans have exceeded over 40 bu/A in past several years.
In order to produce high-yielding soybeans after wheat, you must plant soybeans as early as possible after wheat harvest—and when the soil is fit for planting. Good seed to soil contact is a must for your soybeans to emerge uniformly and with vigor. Baling the straw or planting shorter wheat varieties with light fine straw will assist planters in opening the soil and planting the soybean into the soil at an even depth.
Planting an ultra-early or early-wheat variety benefits farmers who harvest the wheat crop at 18% moisture since they can plant soybeans 8 to 10 days sooner. Planting 1 to 2 weeks earlier means more opportunity for a rain shower in June, which has a big impact on the establishment of the soybean stand. Harvesting full-season wheat varieties at 13% moisture, delays the planting date of double-crop soybeans and lowers their potential yield.
Double-crop soybeans also benefit from narrow rows. Planting at least in a 15-inch row configuration or narrower will help gain quick canopy closure and also will suppress weed growth and conserve moisture throughout the growing season. Planting at 180,000 or higher seeding rates will also stimulate rapid early growth and increase the plant height at harvest. Normally a medium to large seed size variety is also important because at the end of the growing season a larger size seed will be easier to harvest. Also a taller variety will grow and set pods higher for easy soybean harvest. Planting a soybean variety that is a medium to medium-full maturity also will gain more yield.
Tips to increasing the yield of your double-crop soybeans:
• Plant an ultra-early wheat variety—fertilize for 100 bu/A yield
• Harvest wheat at 18% moisture—put into a bin with air and run a stirator.
• Remove straw or use thin straw shorter varieties
• Have good seed to soil contact with soybean seed
• Plant into narrow rows—7 to 15-inch rows
• Plant at higher rates—180,000 or higher
• Plant medium to full-season, large-seeded, tall soybean varieties
Ken McClintock is the 4th generation farmer in western Illinois near the community of West Point. In his seed career he has helped seed companies across the US select high yielding improved genetics of corn, soybean and wheat. His work with plant breeders from both public and private sectors has allowed development and marketing of many high yielding improved varieties. Current responsibilities as the regional manager for Limagrain Cereal Seeds include research and development of soft red winter wheat varieties selected for high test weight and quality grain with superior disease resistance. Limagrain Cereal Seeds web site can be found at limagraincerealseeds.com on Facebook at www.facebook.com/LimagrainCerealSeeds.