No-Spray Columbus

Several studies have shown that monarch caterpillars are killed by the class of pesticides (pyrethroids) sprayed in Columbus for mosquito control. The studies were conducted by the University of Minnesota Monarch Lab researchers using techniques that simulate ULV spraying (the method used by Columbus Public Health to kill mosquitoes).

This is significant because the studies refute the assertion that no damage is done to other non-targeted insects (which is based on an oft-cited study that focuses on the effects of the pesticide while it is still in the air– ignoring what happens when the pesticide finally comes to rest on nearby vegetation).

WHAT TO DO: Opting out of spraying is an easy way to help save monarchs. For other ideas, visit the Monarch Watch website.

For further information about the effects of pyrethroids, studies are available here:

• The Effects of Mosquito-Control Applications of Permethrin on Monarch Butterfly (Danaus plexippus) Larvae
• Effects of Resmethrin Spray on Monarch Butterflies and Larvae (Danaus plexippus)
• Impacts of ultra-low volume Resemethrin applications on non-target insects