18.4.09

The Whole Ladybug Deal

In Latin they are officially referred to as Harmonia axyridis, but locally go by several nicknames: Asian Lady beetles, Halloween beetles, Harlequins, Stainbugs, Ladybirds, Eurasian Beetles, and as one buddy put it: "The lining of my vacuum cleaner."
We've all got them. Even the cleanest home or office fights off their territorial invasion.
They harbored over-winter in our siding, light fixtures, attics, ceilings, sheds, campers, even in our playground equipment. I even found a moving brood of the little orange beneath a pile of last years Maple leaves!
And with the warming temps, they have emerged in some places like a silent invasion of breathing orange carpeting.
While there are over 4,000 varieties of beetle, world-wide, only several hundred are native to this region.
Now they've become more than just a pest or a nuisance, they're pretty gross.

Local beginnings

I first got a whiff of their extent at a Polk County (Wisconsin) committee meeting nine years ago, when Supervisor Dick Coen of rural Luck noted that he and his wife had seen so many that fall, they had "started naming them," as they crossed their living room floor.
"I told my wife, 'hey look, there goes old six-spot!'" he chortled to the property committee.
The laughs slowly turned to the grim realization that everyone on the committee had a similar issue.
We were slowly being invaded by the tiny, dome-shaped insects that gardeners used to love, Germans fashioned a car after and that kids would delicately carry into the house to name and care for in years past.
The cuteness seems to have worn off years ago.
Now they have become an almost accepted part of Midwestern living, and are so numerous, "surveys" of their extent have become unnecessary.

When did they roll into town?

For almost a decade now, the Ladybugs have swelled into a true example of what "invasive species" really means.
The rumors about the causes and the notes of a possible Ladybug invasion started shortly after the first few million were spotted here in the Valley, going back to the fall of 2000, and even earlier to the south and east.
Going backward, "invasions" were noted in Kentucky in early 1992, central Pennsylvania a year later, and Champaign, Illinois in the late summer of 1994. They've slowly marched north during the warm weather, and have adapted remarkably to the climate along the way.

The Hemlock efforts

But where did they all come from? Was it a semi-successful terrorist plot run amok? Maybe a Biblical Plague that never really gained traction? Maybe a kid really did find a Genie in a bottle, and happened to wish for "Lots of pretty little Ladybugs!"
No, no and Definitely NO.
While they have been identified for over a century as a one of the original biocontrol agents for aphids and other pests, there were planned releases noted in the US as early as 1916, but they didn't catch on.
According to several entomologists, it was the US Department of Agriculture that attempted massive releases of the spherical pests several times in the late 70s and early 80s, hoping the multicolored Asian lady beetle would help to control pests in agricultural centers along the East Coast. The target was primarily the dreaded Hemlock Woolly Adelgid, a pest that has single-handedly threatened most flavors of Hemlock tree. In parts of the Northeast, the future for Hemlocks is grim at best, and the USDA apparently saw the writing on the wall years ago, and tried - unsuccessfully, it seems - to introduce the Ladybug as a last ditch way to save the trees.
The New Orleans theory
Entomologists have tried to trace them genetically, and seem to think the US infestation essentially ALL came from one initial batch, but pinpointing where that colony entered may be twenty years too late.
The beetles were noted in Louisiana in late 1988, although most science-types think that batch may have been an accidental release, possibly from a Japanese cargo vessel or cruise liner in New Orleans. They note that the critters were never released in those areas they were first spotted that year, so the fingers point away from the earlier USDA southeast releases, and may lean toward a new source.
Others have noted the use of the Ladybug as a way to help control aphids on Pecan and Apple crops in the Deep South, from private producers, and that the invasions may have caught on and spread fast, since the warmer weather allowed them to produce many times their usual four to five generations per year.
Where are they?
Whatever the cause, and wherever they entered the US, they are here and they are almost everywhere. The bugs have now been confirmed from far eastern Canada down to Florida, and all along the Atlantic seaboard and mid-Atlantic states. Of course, they have been here and throughout the Midwest and are now even into the Pacific Northwest, where they have become so prominent in Oregon and Washington, shipments of everything from apples to Christmas trees must be inspected, so they don't spread any further. California vintners have made extra efforts to eliminate the bugs, since even a few on the grapes can taint entire batches of wine.
What can we do about them?

But the real issue has become how to control, or at least limit them, since they have no natural enemy - except maybe the Shop Vac.
The problem is that they sort of "communicate." They don't really speak their own language, per se, but communicate via smell - a pheromone, actually. It's called an "Aggregate Pheromone," and when one of the little beasts discovers a nice, safe, warm place to hide out when the weather gets cooler, it realizes that smell, and all the ones around pay attention and flock to that spot.
Those flocks can number from a dozen to tens of thousands, and there have been reports of massive colonies found behind siding or in vents.
They tend to favor the south and west side of buildings, especially areas warmed by afternoon sun. They are also drawn by sharp color contrasts, especially light colors of siding.
The critters are tiny, and they probably do not want to be trapped in your home.
The best trick to eliminating them is to keep them outdoors. Weatherstripping, caulking, sealing holes and obvious entry points will help dramatically.

But they have this spray...

Chemicals and pesticides can and do work, to some extent, but should only be applied outdoors. Many professional think you should only use pesticides as a last resort, and even then, only in the early fall or late summer, to keep them from over wintering.
Would you want thousands of dead ladybugs in your attic or in your walls? It really is best to keep them outside, and use pesticides only as a deterrent. Without mentioning names, there are a number of proven pesticides that work pretty well on the beasts, but many are quite toxic to plants, pets and other critters.

And the good news?

Regardless of our efforts or their numbers, they are probably here to stay at some level.
Yes, they really do a good job of controlling crop-eating aphids, and if you want to control them humanely, it's wise to apply them to a garden.
Efforts and studies are underway to control them biologically, even at a genetic level. One notable area of research involves genetic manipulation to make the bugs nearly flightless, so future generations would be less mobile and likely to spread. Some of these strains are already being used in some controlled environments.
Other tests have proven worthy, although slightly gross: They essentially turn the critters into cannibals during one of their earlier stages, decreasing the number of males so dramatically, they don't even need to wear cologne or buy fast cars to attract females.
Hate them or not, Ladybugs are considered sort of the coolest invasive species. In fact, the Mall of America reportedly releases them ON PURPOSE to keep their over 400 indoor trees pest-free.
Other regions of Europe and Asia have dealt with the critters for decades, and still have a positive view. Some western Europeans even relate to the bugs in Biblical terms, with several nicknames associating them with the Virgin Mary. And several cultures still consider them good luck and positive fortune.
One long-held myth was that killing one was bad luck.
If that is true, then forget broken mirrors and seven years; my Shop Vac has doomed my great grandchildren.



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