Ladybugs make presence known

News

November 4, 2015 - 12:00 AM

It was almost as if Carla Nemecek were expecting the phone call from a resident curious about the swarms of ladybugs that started cropping up over the weekend.
“You mean the Asian lady beetle?” asked Nemecek, Southwind Extension agent for agriculture. “Yes, we know all about them.”
The ladybugs — also known as harmonia axyridis or multicolored Asian lady beetles — have grown more populous in recent falls, to the point that a walk outside Sunday revealed dozens of the little critters fluttering about.
Nemecek provided information about the lady beetles, and how homeowners can protect their interiors.
Among the highlights:
The large and colorful ladybugs are easily identified by the large, black “W” on the thorax behind the head.
The background coloration of the wings varies greatly, from yellowish to pale orange to bright red, depending on the type of food consumed in the larval stage.
Spots vary in number and intensity, and typically are genetically determined.
While lady beetles are generally recognized as beneficial insects for their ability to consume large numbers of garden pests such as aphids, the Asian lady beetle is another story.
That’s because this particular species has displaced many less competitive native lady beetles from particular habitats. It has since reached the point that it poses a threat to the biodiversity in some ecosystems.
The Asian lady beetle also causes problems in fruit crops such as pears and peaches because of its habit of nibbling on ripe fruit. When abundant in vineyards, it can affect the flavor in certain types of wine production.
But for Kansans, the biggest source of irritation is how the beetles try to make it indoors as the weather cools.
As the days shorten, the lady bugs tend to gather in clusters and seek to enter protected sites for overwintering, such as barns, sheds and houses.
The beetles are most active on warm fall or winter days, such as what eastern Kansas has experienced this week.
They tend to be attracted to pale-colored or white buildings with good exposure to sunlight.
Not only can large numbers of the Asian lady beetles create an offensive smell and foul living quarters, they can cause allergic reactions in some people and have been known to nip the human skin with their mandibles.

PREVENTION
The best means of preventing infestations is to keep the pests outside, Nemecek noted.
Homeowners should seal all gaps around windows, door frames, eaves and soffits with caulk, silicone or other suitable compounds.
Pesticide barrier sprays applied along cracks and other points of entry can help, but only if done by a certified applicator.
Removing the lady bugs is best done with a broom and dust pan, or with a vacuum cleaner.
The vacuuming process will kill almost all of the lady beetles, so homeowners needn’t worry about the insects crawling back out.
Removal is best accomplished in cool weather, such as evenings, when the beetles are unable to fly.

NEMECEK welcomes calls from folks curious about Asian lady beetles or other entomological questions.
She can be reached at 365-2242.

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