UT Extension News: Ladybug, Friend or Foe?

November 15, 2021

By Chris Hicks, County Director – UT Extension Smith County

I took the afternoon off one day last week to do some work on the farm. I was looking forward to a relaxing evening of tractor time with 65-degree temperatures. What I got was an afternoon of swatting at thousands of ladybugs, which seemed to follow me wherever I went. 

While I can appreciate that ladybugs can be very beneficial in crops or gardens since they eat a ton of aphids and other pests, on this day I had trouble focusing on their redeeming characteristics. You likely have felt the same way if you have had them invade your home. 

This time of year, we always get several calls about insects that have made their way into houses. The number one home invader we get calls about is the Multicolored Asian lady beetle, with stink bugs being a close second. Not only are they a nuisance since even the most fun-loving entomologist doesn’t want to sleep with insects crawling on him, but these critters literally “stink” when disturbed. 

Exclusion is the first step a homeowner should consider when these critters come around. Door sweeps, weather stripping on garage doors, and caulking around window frames will eliminate many entry points. Don’t forget about mesh screen around vent openings and use expandable foam around outdoor faucets and other pipes that lead inside. 

For any insects that make it past your exclusion efforts, trapping and vacuuming are the methods of choice. Glue traps near suspected entry points will catch these pests and give you an idea of where you need to improve your exclusion endeavors. There are also commercial and homemade traps that are fairly effective. 

I don’t recommend using an insecticide to kill these pests once they have entered the home. After all, they will still have to be vacuumed. The use of “foggers” is discouraged since fogging only kills the beetles contacted by the spray, while those in cracks and crevices are unaffected. Many dead insects, in inaccessible spaces, may attract carpet beetles and other pests of food and fiber.

I do sometimes recommend the use of insecticides outside the home to supplement pest-proofing techniques. Remember, these chemicals are designed to kill living things so be smart and read and follow the label, and if you’re in a position where you can, consider hiring a trained professional to apply them. 

While they are wonderful to have in crops for pest control, lady can be a frustrating and embarrassing issue for homeowners this time of year. The UT Extension office has a great list of publications with tips on exclusion methods and management advice. Check them out under the “publications” tab at smith.tennessee.edu or stop by our office at 125 Gordonsville Hwy in Carthage and we will be glad to print them for you.