Grit Blogs > Of Mice and Mountain Men

Why Lady Bugs are Neither

If you live in or near a wooded area, you most likely play host to an unwelcome house guest every fall: lady bugs. 

Native LadyBird BeetleIt is interesting that this colorful and much celebrated insect is neither a bug nor always a lady.  Like anything that reproduces sexually, the species consists of both male and female, so some ladybugs are male!  And because ladybugs have biting mandibles for tearing their food, not the sucking mouthparts commonly found on “bugs” these creatures are more correctly classified as beetles.  Technically, the proper common name for these brightly colored, hard shelled flying insects is “ladybird beetle”, but it’s OK if you prefer to call them lady bugs; most everyone does.

Lady bugs are handy helpers in the garden because both the hard shelled adult and the alligator head shaped larva are voracious eaters of aphids, scales, whiteflies, mealybugs, thrips, mites, caterpillars and beetle larvae.  In fact a single lady bug can consume 5000 of these pests in its lifetime.

 Asian LadyBird Beetle 

Native American lady bugs are not much of a nuisance, but the Asian lady bug which was deliberately introduced into the United States by the U.S.D.A. to control certain pests, such as the hemlock woolly adelgids, which has been decimating the old growth hemlock trees of the Great Smoky Mountains National Park, have bred, spread and become something of a pest themselves.  Not only do they displace the native and more beneficial ladybird beetles, but these lady bugs swarm in the fall and invade homes in large numbers.  They emit a nasty smelling liquid when disturbed and will bite humans.  Generally these beetles are a red-orange color with black spots, but the easiest way to identify them is the black M shaped spot pattern on white background just behind their heads. 

To rid your home of lady bugs, be sure doors and windows seal up tightly; they can wriggle through surprisingly small cracks.  Then cut 6 to 8 inches off the toe section of an old pair of nylons, slip this “bag” into the end of your vacuum cleaner wand, leave an inch or so of the nylon out to fold over the end of the wand, then hold it in place by slipping your crevice tool over the end.  Now you can use the vacuum to suck the lady bugs from walls, ceilings and around your lights.  Remove the bag and empty the lady bugs in your garden where they will do more good than in your home.

To attract lady bugs to your garden, do not use pesticides.  You may notice more pests, but if you also see lady bugs, it will balance out.  Lady bugs also feed on pollen and nectar, so planting wild flowers around your garden or letting a portion of your land near the garden go “wild” will also bring in more of these natural pest patrollers.

If you see larval or adult lady bugs in your garden, it is a sign that your garden is in a natural balance.  Perhaps this is where the thought that lady bugs are harbingers of good luck came from!