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Kyle’s News and Reviews

Prepare For The Lady Beetle Invasion


Saturday of last week I had the joy of taking my son Levi to the Mississippi State vs UMass game in Starkville.  Even though I work for Mississippi State, I haven’t been to a football game in over 10 years and we had a great time seeing old friends before the game, watching the game in the expanded stadium and seeing old friends and playing after the game.

  

The Bulldogs did not play very well but they still won and that is all that matters.  Levi is only six years old but, to my surprise, he did not want to leave the stadium until the game was over.  The weather Saturday was warm and humid and with the attire being blackout, when the sun was shining it was almost hot.


I have heard several people say over the last few days “where did the fall weather go to?”


I am not the smartest person in the crowd but I have lived in Mississippi long enough to know that if you don’t like the weather today, just wait until tomorrow it will change.  Over the last month and a half we had gotten into a little dry spell and maybe even drought conditions in some areas, but over the last two weeks we have received a little rain to help with that.  The cold temperatures a couple of weeks ago followed by the warm humid temperatures have really brought out the invasion of the lady bugs.  Dr. Blake Layton talks about the Asian Lady Beetles in his news feed this week:


The multi-colored Asian lady beetle, Harmonia axyridis, specializes in preying on tree-dwelling aphids and this year’s outbreak of Asian wooly hackberry aphids, combined with large numbers of crape myrtle aphids, has resulted in a bumper crop of Asian lady beetles.  As fall approaches, these lady beetles will be looking for a place to spend the winter. In their native country they congregate in light-colored rocky outcrops, where they overwinter in cracks and crevices among the rocks.

  

Here in Mississippi we do not have many rocky outcrops for these insects to use as overwintering quarters, but light-colored buildings seem to make a fine substitute. They are especially attracted to buildings with an un-shaded western or southern exposure.

 

Once the lady beetles land on the side of the building they search out cracks and crevices, which results in their entry into wall voids and attics where they often congregate in large numbers. 


As temperatures warm in the spring, overwintering lady beetles begin to search for cracks and crevices through which to leave their overwintering quarters. Many of these beetles ‘get lost’ and find their way into the inside of the building, rather than the outside.  


Whether they invade the home in the fall, during warm spells in winter, or during the spring as they attempt to leave their overwintering quarters, these otherwise beneficial insects can become a serious nuisance, especially when they occur in large numbers. The best way to avoid this problem is to prevent them from entering the home in the first place, and that means taking steps to make the exterior of the home ‘bug-tight’ before these insects begin searching for overwintering quarters.  


The key is to seal or screen any opening that is greater than 1/16 inch in diameter. This is easier to do on some homes than others. Homes that have overlapping board-type siding nailed directly to the wall studs, without any type of solid wallboard in between, are especially problematic, because there can be literally hundreds of feet of potential entry points. 


However, on many homes it is relatively easy to identify and seal potential entry points, and taking the time to do so now can avoid much frustration later in the winter.  


Doors and windows are obvious potential points of entry and installing sweeps on door bottoms, and metal spring strips or weather stripping around door jambs can help keep lady beetles from entering at these points. Entry points around plumbing and conduit can be sealed with caulking or foam sealant, as can cracks in brickwork and woodwork. One of the most important steps is to check all attic, roof and soffit vents to be sure that they are adequately screened and bug-tight. 


Unscreened soffit vents can be a prime point of entry, but lady beetles can also enter around screened soffit vents if they do not fit tightly against the soffit. Many homes have ridge vents or other types of vents on the roof through which beetles can enter if they are not properly screened. Special attention should be given to proper screening of the large gable vents that are located on the ends of many houses. 


It is important to emphasize that exterior screening and sealing efforts must be completed before the beetles enter the building. Insecticides play very little role in managing invasions of Asian lady beetles. However, residual sprays of synthetic pyrethroid insecticides can be applied to exterior walls of ‘invasion prone’ buildings in an effort to reduce the number of beetles that successfully enter the building.

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