View from the Cab: Stay Vigilant

By: Kent Casson

Now that Easter is behind us, it is practically time to plant corn, although the recent cold and wet weather pattern needs to turn around quickly.

The 2022 spring planting season has yet to take off around here, but one of these days we will be working nonstop to put this year’s corn and soybean seeds in the ground. Once the first of May arrives, it will be crunch time for planting. Otherwise, our yields could take a hit in the fall for each day planting is delayed.

Another factor which could impact yields is corn rootworm. Agronomists are concerned growers could see an increase in rootworm pressure during 2022. In recent years, populations have risen and the drier fall followed by mild winter likely led to lower pest mortality.

AgriGold agronomist Terry Mente notes farmers can lose around 15 percent of their yield potential per ring of nodes that are pruned by rootworm in an average year. The impact may be less severe in a wet year but if conditions are dry or nutrients are marginal, losses can be amplified.

Northern Illinois AgriGold agronomist Kevin Gale has also observed an increase in rootworm populations.

“It’s important to be cognizant of what’s needed rather than using a blanket approach for battling the pest, especially on ground that has been corn-on-corn for several years,” Gale said. “Switching up modes of action or including an insecticide may be warranted in some fields for maximum root protection.”

Mente said problems are often spotted during harvest when farmers are too busy to stop working to do some digging. The two species of rootworms impacting producers the most in the Midwest include Northern Corn Rootworm and Western Corn Rootworm. Larvae usually begin hatching and feeding on roots in late May or early June.

Rootworm can be spotty in fields as they like to lay eggs in moisture and replanted fields are prime candidates of where those rootworms are going to go because of later flowering or late silking. Trait selection can be the first line of defense after determining corn rootworm is a threat. It is recommended growers rotate below ground trait protection modes of action.

Repetitive management practices can lead to rootworms adapting, especially in those corn-on-corn environments. If the same technology is grown each year, the rootworm population will likely do more injury to the root and rotating modes of action is more effective.