Plague of Pests

If you enjoyed the early earthy morel or the delicate blooming of lilacs ahead of schedule, know this—the dreaded seed corn maggot cometh too. These three harbingers of spring are typically in sync, and remained so this year, all of them three weeks early.

Wisconsin winters offer a huge pest management advantage over more southern climes, where farmers have to manage aggressively for resident insect pests year-round. A little extra heat and a little extra time is a compounding problem. For the onion thrips it can be the difference between a single female breeding 30,000 replacements—or 15 million.

CALS/UW Extension entomologist Russ Groves says the balmy March drew a lot of insects out of hibernation, including the dreaded
Colorado potato beetle—also three weeks early.

Meanwhile, non-resident pests arrived ahead of schedule. Farmers have been taught to start looking for the potato leafhopper by the first of June. This year, it arrived by May 10. “Growers are going to have to reset their clocks,” says Groves.

The squash vine borer and squash bugs are just two pests that have established full-time Wisconsin residency in the last 20 years, says Groves. “If that happens with the seed corn maggot, that could really change the pest landscape.”