As the economics of corn drive more farmers to move toward corn-on-corn production, they are often faced with additional challenges not typically encountered in a traditional corn-soybean rotation. In order to maximize the potential for high yields in corn on corn, farmers need to focus on several agronomic factors. "While a traditional corn-soybean rotation is often the best way to minimize agronomic challenges, many factors encourage farmers to cultivate corn on corn, and the number of acres has risen dramatically in recent years," says Ty Vaughn, Monsanto's corn product management lead. "However, there are a number of consequences to this practice, and increased attention to agronomic practices is required when you are growing corn-on-corn."
Vaughn and his colleague, Luke Samuel, recently met with Wallaces Farmer staff in Des Moines and discussed best management practices for growing corn on corn and managing corn rootworm pressure.
Carefully evaluate performance when choosing hybrids for corn-on-corn acres
This summer in heavy corn rootworm pressure areas Monsanto plans to host a number of corn-on-corn clinics focusing on some of the agronomic factors associated with corn-on-corn production. Agronomic factors that need to be considered in corn-on-corn production include, but are not limited to, residue management, seedbed preparation, soil fertility, weed control, disease pressure and insect pressure.
"Because every field is unique, we encourage growers to carefully evaluate the emergence scores, disease tolerance and insect protection component of each corn hybrid when making selections for corn-on-corn acres," says Vaughn.
Hybrids incorporating Bt proteins for insect protection and traits to provide herbicide tolerance have been shown to help alleviate the stresses that the environment places on corn-on-corn production. Healthier corn plants can withstand greater environmental stress, which typically results in higher yields.
Corn rootworm control is critical for successful production of corn on corn
Insect control is particularly a key factor, and a critical pest in corn-on-corn production is corn rootworm. "Farmers who choose to plant corn on corn need to ensure they understand the importance of integrated pest management practices when managing high corn rootworm populations on-farm," says Luke Samuel, Monsanto's corn insect product development manager. "History has shown us that hard-to-control weeds and insects may require a combination of practices to help manage them, but the end result is to increase effectiveness and yields."
Scouting your fields is an integral part of insect management, emphasizes Samuel. Because adult corn rootworm beetle counts help estimate the extent of corn rootworm larval damage a farmer might expect the next year, Monsanto recommends field scouting for adult corn rootworm beetles during the key months of July and August when peak corn rootworm flight activity occurs.
"If a farmer is experiencing heavy rootworm pressure and unexpected feeding, the best choice is to rotate to soybeans next season," says Samuel, "but that may not be a choice farmers can make, or that they are willing to make, given the economics of the situation. Some farmers need to plant corn on corn because they need the feed for livestock, or they want to plant corn on corn because they can make more money doing that rather than rotating corn with soybeans."
What if you can't rotate corn with soybeans or if you don't want to rotate?
Planting pyramided corn seed products, like Genuity SmartStax RIB Complete corn blend is one option. So is using a soil-applied insecticide in fields where you are planting single mode of action corn hybrid products. Or you may even want to consider using an adult rootworm beetle control program by spraying an insecticide to limit the amount of egg-laying females later in the season. "These are all potential tools to use in heavily infested corn rootworm areas," says Samuel.
Monsanto offers a wide selection of corn products with different hybrid characteristics and trait packages that can be planted successfully in a corn-on-corn situation, says Vaughn. "Our seed dealers, sales representatives or agronomists work with growers to understand the circumstances and the history of their fields to provide solutions that maximize productivity," he adds.