New York State IPM Program

March 28, 2018
by Joellen Lampman
Comments Off on Managing monsters: Ladybugs problematic for many this winter

Managing monsters: Ladybugs problematic for many this winter

Originally published on March 24, 2018 – Courtesy of Paul Hetzler, CCE St. Lawrence County

Unlike for vampires, there are no silver bullets for Harmonia axyridis. But good screens certainly help.  Photo: John Flannery

Pest management used to be a lot simpler, and more effective. For those bothersome vampire problems you had your basic wooden stakes, cheap and readily available. The well-to-do could afford silver bullets, an elegant and tidier solution. And of course, garlic was the solution to prevent repeat infestations. These days many people are asking where to find teeny silver bullets for Asian multicolor lady-beetles, because they are a real problem this winter.

On sunny fall days, the Asian multicolored lady-beetle, Harmonia axyridis, often hangs out with its pals on west or south-facing walls. The insect may be beneficial for gardens and harmless to us, but as winter approaches, these insects quit swarming to seek shelter in outbuildings, wall cavities, firewood piles and other nooks and crannies. Eventually, some of them find their way inside our homes. I don’t know what the sanctioned collective noun is for a gathering of Harmonia axyridis, but it should be a drove, since they can be enough to drive you out of the house.

From what I can tell, the orange-and-black ladybug, darling of small children everywhere, first arrived in the U.S. — at our invitation — in about 1916, as a control for aphids on pecan trees and other crops. Adorable lady-beetles didn’t turn into ogres until the mid-1990s. There is evidence to suggest the current population might be a strain accidentally released at the Port of New Orleans in the late 1980s or early 1990s. Whatever their origin, these new lady-beetles are here to stay.

Asian multicolored lady-beetles don’t carry disease, damage structures, suck blood or sting, and they eat harmful agricultural pests. More importantly, they do not breed indoors. However, they stain, give off a foul odor when disturbed and will even pinch one’s skin on occasion. It’s their sheer numbers, though, amassing in corners of garages and porches, coating the insides of picture windows, which unnerves and bugs us.

Managing ladybugs, it turns out, can cut your heating bill. Caulking around windows, vents and where cable or other utilities come through the wall, and between the foundation and sill, will help immensely with lady-beetle control, and somewhat with reducing drafts.  Photo: Joellen Lampman

Managing ladybugs, it turns out, can cut your heating bill. They are looking for someplace rent-free and cozy to spend the winter, and as warm air leaks out here and there from your house, they follow it to its source and let themselves in. Caulking around windows, vents and where cable or other utilities come through the wall, and between the foundation and sill, will help immensely with lady-beetle control, and somewhat with reducing drafts. It is also helpful to ensure that door sweeps/thresholds are tight, and check for cracked seals around garage doors. Installing screens on attic vents and inspecting all window screens is in order as well.

It’s best to avoid swatting or crushing them because they will release a smelly, staining yellow defense fluid. For a variety of reasons including the ladybugs’ habit of seeking inaccessible areas, indoor pesticides are practically useless against them. Spraying inside is strongly discouraged. Instead, use a broom and dustpan to knock them down and then suck them up with a vacuum cleaner or shop-vac.

You can use a simple knee high stocking to ensure vacuumed lady-beetles don’t end up in the vacuum bag or canister and can be easily dealt with.  Photo: Jody Gangloff-Kaufmann

You can make a reusable “mini-bag” out of a knee-high nylon stocking inserted into the hose of a canister-type vacuum. Secure it on the outside with a rubber band and hang onto it as you clean up the bugs. Just remember to quickly empty it into a pail of soapy water (gas or kero is hazardous and unnecessary).

Unfortunately, there is no easy way to combat multicolored Asian lady-beetles once they are inside — we have to persevere and vacuum and sweep them out for now. Home improvements this summer will help prevent repeat bug visits. I have no doubt that it must be more satisfying to dispatch vampires in one easy step than to fight endless lady-beetles, but I would bet it is a lot more dangerous, too.

Contact Paul Hetzler of Cornell Cooperative Extension of St. Lawrence County at ph59@cornell.edu.

For more information on multicolored asian lady beetle, brown marmorated stink bugs, boxelder bugs, and other occasional invaders, check out How to deal with occasional invaders on the New York State Integrated Pest Management Program’s What’s Bugging You? page.

Are you ready for fall invaders?

September 10, 2015 by Matt Frye

Insects exhibit a variety of behaviors or adaptations that help them to survive the harsh conditions of winter. One that can be quite frustrating to homeowners belongs to the the group of insects we call “overwintering pests.” These organisms survive winter by taking refuge in South or West facing cracks and crevices, which maximizes exposure to the warm sun and buffers them from wind and freezing cold. While trees and rocky hillsides provide overwintering sites in nature, man-made structures that now dominate the landscape are perfectly acceptable to these insects.

The Culprits. Multicolored Asian ladybird beetles, boxelder bugs, western conifer seed bugs, cluster flies, and the brown marmorated stink bug are common fall invaders in the Northeast. Some of these insects are exotic invasive species that were accidentally introduced to the US, such as the stink bug, which was first identified from samples collected in Allentown, Pennsylvania in the 1990’s. A new insect, the kudzu bug, was introduced to Georgia in the early 2000’s and may soon invade homes in the Northeast.

Note the light and dark bands along the edge of the body.

Brown Marmorated Stink Bug [note the light and dark bands along the edge of the body]

Boxelder

Boxelder Bug [center of 3 stripes partially covered by pin]

IMG_0899

Western Conifer Seed Bug

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Multicolored Asian Lady-Bird Beetle [note “M” pattern on white thorax]

Can they be Stopped? If overwintering pests gain access to buildings through cracks and crevices, it seems reasonable that sealing these openings will keep pests out. While no formal research has tested this hypothesis, a recent grant awarded by the Pest Management Foundation will evaluate the effectiveness of exclusion as a technique to keep stink bugs and other overwintering pests out of homes (Note: the Pest Management Foundation is the education, research and training arm of the National Pest Management Association). In the mean time, below are some common recommendations to dealing with overwintering pests:

  • Using an appropriate sealant labeled for doors and windows, seal exterior gaps that could allow entry into the home. Remember to inspect locations where wires, pipes, and other utility lines enter the structure, especially on the South and West facing side of buildings.
Screen Shot 2015-09-09 at 4.03.58 PM

Look for and seal gaps around window and door frames.

Repair torn screens

  • Make sure that screens are tight fitting in the window frame, and they do not have any tears.
  • Keep attic doors and fold-down stairs closed during winter months. Insects can enter attic spaces through soffits, later entering the livable space when they are attracted to lights and heat.
  • Flues should be closed in the fireplace when it is not in use.

Trapping Pests. On warm winter days, stink bugs and other overwintering pests may become active. During the day, they can be found at windows, while at night they may fly towards artificial lights from the television, computer or lamps. One indoor trap type that is easy to make and effective is a pan trap. Read more about this device here: Stink bugs beware! Homemade stink bug traps squash store-bought models, Virginia Tech researchers find.

Additional Resources:

Brown Marmorated Stink Bug Factsheet

Brown Marmorated Stink Bug Prezi

This gallery contains 5 photos

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