WICHE: A lady beetle invasion common this time of the year

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They won't really hurt anything, but they are sort of a nuisance.

By Jeneen Wiche

Some years are worse than others: I remember years when it was like a siege of lady beetles other years a few popped up here or there. Usually they sneak their way into our homes as a noticeable chill settles in.

On sunny days they cling to the screen door on the south side of where I write. Presently they are displayed before me.

I need not worry about them as they sun themselves. But the ones that collect indoors, well your best bet is a vacuum cleaner!

The perceived invasion is as simple as looking for a little warmth and protection from winter weather. The invader is not your average ladybug. It’s an Asian cousin imported years ago by USDA Agricultural Research scientists.

The USDA introduced the Asian lady beetle to the United States as a biological control against pear psylla and other soft-bodied insects. The Asian lady beetle, harmonia axyridis, is a voracious eater, just like our native lady beetle, but they have different wintering habits.

The Asian lady beetle is native to Japan and Korea, where they winter over in cliffs in order to stay warm and protected from inclement weather. In the United States, in the absence of cliffs, the lady beetles flock to vertical structures, often light-colored, and always south or southwest facing.

These vertical structures are usually our homes.

They appear copper-colored and exhibit a great deal of variation within the species. Sometimes they appear with no spots, a few spots or many spots. Usually they are a copper or burnt orange color, but they can appear black or red. Do not be surprised or confused by these variations.

If there are cracks, crevices are any point of entry the lady beetles find their way indoors collecting on walls and ceilings. As numbers increase so does the desire to get rid of them but it is somewhat problematic.

Lady beetles are beneficial insects, eating other nuisance insects, so killing them is environmentally irresponsible. However most people do not want lady beetles in their house all winter long.

No. 1 in beetle-proofing your home is to seal up crevices, install weather stripping around doors and check for any other entry point.

his will not only eliminate the number of insects that come in it will also reduce your utility bills in both summer and winter.

Removing those beetles that have already made their way inside is best done with a broom or a vacuum. I know that it is asking nearly too much, but instead of killing them, try sweeping them up and releasing them a good distance from your home.

If you do crush them, be ready for the stinky smell they will emit. And don’t forget to empty the vacuum if you vacuum dead ones up.

The problem with using chemical sprays is that it will only kill those insects that it comes in contact with, and likely there are more beetles in unseen places. If you fumigate and kill those that are unseen, then other insects that feed on the carcasses may be attracted to your home as a result.

Lady beetles feed on soft-bodied insects and will not do any structural damage to your home, but those that may feed on them can. They are just hibernating in your home and will not bite (although some have insisted otherwise), sting, spread disease, infest your food or eat your clothing…they are just annoying.

If you do choose to use chemicals, do so in late September ,when you notice them on exterior surfaces before they enter the home.


Check out gardening columnist Jeneen Wiche’s work at www.SwallowRailFarm.com. You can find her columns also at www.SentinelNews.com/agriculture. She answers questions once a month in SentinelNewsPlus. To submit a question, send an E-mail to jwiche@shelbybb.netand type “Sentinel-News” in the subject field.