Aug 4, 2023 - Climate

Small worms pose big threats for Colorado corn crops

A field of corn growing on a Grand Junction farm in 2022. Photo: RJ Sangosti/The Denver Post via Getty Images

Yet another insect is wreaking havoc on the Centennial State, thanks to a deluge of downpours this spring and summer. The result will mean less corn at the grocery store.

Driving the news: Colorado's largest corn producer, Tuxedo Corn, is only packing about 3,000 boxes of corn a day — three times less than the amount in a typical season, the Colorado Sun reports.

  • The culprit is corn earworms, also known as tomato fruitworms or cotton bollworms, which have infested at least 30% of the sweet corn crop between Montrose and Delta.

Why it matters: Colorado's corn crops are estimated to generate $15 million in annual revenue for the state and serve as a critical source of income for farmers and workers.

  • Sweet corn is also a summer staple. Without it, the season seems almost incomplete.

What they're saying: "We have an EMERGENCY in sweet corn production in Western Colorado," John Harold, who founded Tuxedo, recently wrote to Democratic Sen. Michael Bennet in hopes of receiving help from the federal government.

  • "We are scrambling. We are off balance. We are sad. We are embarrassed. We did not see this coming," Harold's son, David, who helps run the company, told the Sun.

What's happening: A "perfect storm" of factors, including ample early moisture after years of drought, is boosting the worm's populations, says Melissa Schreiner, an entomologist for Colorado State University Extension.

  • Another reason suspected behind this year's unprecedented surge is strong southeastern winds, which may have propelled migration of the moths that lay the worm eggs.

The intrigue: Insecticides that growers spray on the crops to ward off the worms didn't work this year.

  • The anomaly is now at the heart of a study Schreiner and the Harolds are conducting to find out whether the worms have developed a resistance to the pesticides used to kill them in the past.

Between the lines: The Harolds told the Sun that legislative and political restrictions — like a state law that gives farm workers greater protections and the demands of H-2A visas for foreign workers — are exacerbating the corn production problem.

  • Further compounding the issue is a shortage of workers and lack of infrastructure to process defective corn, they say.

Be smart: Corn with worm defects is perfectly edible, experts say.

  • Larvae tend to clutter on the tips of healthy ears of corn — so, should you find a critter or two, simply cut off the top and the rest is still good to bite into.

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