[Occasional Invaders] Beetle Invasion

One of the things I love about my job as a pest management professional is the
opportunity to learn and see new things; Asian lady beetles are a perfect
example. Over the past few years, these pests have proven to be a new source of revenue and have given us an opportunity to solve problems for our customers.

WHY A PROBLEM? The main species of Asian lady beetles that homeowners call about is ¼- to 3/8-inch long. The elytra are mustard yellow to dark reddish orange, normally having several black spots. However, the spots may be indistinct or absent. This lady beetle is found throughout most of the United States and parts of Canada.

Asian lady beetles were released at numerous locations across the United States on several occasions by the U.S. Department of Agriculture to help reduce populations of aphids, scale insects and mealy bugs (all which are crop and fruit pests). This beetle has adapted well and has multiplied in such numbers that it has now become quite a problem in many structures.

When they move into a structure, they are looking for a place to overwinter. Then the warm days arrive and they enter the living area, many times by the thousands. Overwintering adult ladybugs emerge from hibernation and deposit their orange eggs in single or multiple groups. They are looking for plants infested with aphids, mealy bugs and scale insects. The larvae molt four times and the mature larvae attach to leaves by the tip of their abdomens and pupate without forming a cocoon. The larvae and adults prey on aphids, mealy bugs, scale insects and other soft-bodied insects and their eggs, which makes them beneficial.

The problem comes in the fall, when adults are looking for the perfect place to overwinter — homes seem to be a favorite wintering spot. They hibernate in various cracks, crevices and wall voids. On those nice warm days in January and February, they pour into the house, causing intense panic. The invasion has begun! The only effective weapon at that point is a vacuum or an indoor treatment in the affected area. It’s at that time that the pest management professional should educate the consumer about the life cycle and habits of these insects and inform them that these "pests" are beneficial.

CONTROL OPTIONS. The customer should vacuum the present insects and change the vacuum bag often, as they do have a foul odor. Do not dust cracks, crevices and wall voids or you may create a larger problem with predatory insects feeding on the carcasses.

Make an appointment to treat the inside areas where the ladybugs are coming in so they die quickly and don’t move into the other parts of the house. If it’s later in the spring, powerspray the outside perimeter when customers see lady beetles on the siding. (The beetles will die when they land on the siding.) Then help your customer prepare for winter, because if they had an invasion this year, it’s almost a given they will have another one next year.

Look at the house to see what needs to be sealed to block the invasion. A little caulk can go a long way to exclude these pests from the structure. A July powerspray around the perimeter of the house will control occasional invaders such as spiders, crickets, etc., as well as limit ladybugs. Also, focus on landscaping around the structure. Powerspray again in September to treat before they try to move in. It’s a good idea to dust under the siding with a repellant dust to send them in another direction.

See the chart at left for a treatment schedule, which may help you protect homes from unwanted guests. Again, caulk entries and put a barrier treatment outside. You will find these are amazing creatures. Scott Steckel of Varment Guard in Columbus, Ohio, reports a growing number of ladybug calls and some reports of painful bites from these insects. He said he relies heavily on exclusion techniques. Mike Scholes of Reliable Pest Control, Hannibal, Mo., has found that boxelder bugs are frequently present with the ladybugs.

The author is president of Holper Pest & Animal Solutions, St. Louis, Mo. He can be reached at jholper@giemedia.com.