Are you ever left wondering about wasp wanderings?

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By Staff Brunswick Beacon

The trend toward cooler weather is welcomed by most of us, but some unwelcome insect visitors can accompany it.

Polistes, or paper wasp colonies, are beginning to die out and some of the remaining workers (who will croak eventually), along with next year’s crop of queens, are likely to start bailing out of nests. The surviving queens will seek out some place to pass the winter and all too often our houses become the location of choice. There are several species of paper wasps, but the common ones are mostly brown in color with yellow stripes on their abdomens.

You will likely see wasps outdoors hovering about the eaves, soffits and even porches. The wasps seem to orient to vertical objects, so structures such as chimneys and cell phone or other utility towers become the objects of the wasps’ attention.

At some point, the wasps manage to make their way indoors and things can get more exciting. The wasps are often seen moving about slowly and bouncing off windows, ceilings, light fixtures, etc. Another semi-reliable sign of indoor wasp activity is to watch your pet cat. Of course, cats will stare at absolutely nothing for hours but the true sign is when the cat proceeds to bat the wasp back and forth with its paws before chewing on it and spitting the carcass (along with a hairball) at your feet.

Trips to the attic can be adventurous as people often spot multitudes of the wasps buzzing about. Cold weather seems to stop the activity, but quite likely on subsequent warm days you will find wasps flying about indoors or again spot them outside around the roof area. In many cases, the wasps may be gaining access around the A/C vents in floors or ceilings particularly where the vent is passing through either the crawlspace or attic.

There are a few noteworthy points that are usually of little comfort to the frantic who spot the wasps. This may be more complicated if they are seen at nursing homes, day care centers and other such facilities where managers are concerned about stings (and lawsuits) and so they want to unleash every chemical weapon in the pest control arsenal.

Seeing wasps does not mean there is a nest in a wall. More likely, there is a nest (or several nests) outdoors on a roof overhang, under a porch, in/on a tree or some other protected area.

Since these are mostly queens (and a few workers living out their final days) and they are looking for winter resting sites, they are not aggressive and so stinging incidents are rare unless you have a “close encounter of the Polistes kind” such as I had when I laced up my running shoe one morning only to discover a wasp had crawled inside there during the night.

Spraying indoors as a preventive strategy is an exercise in futility and an unnecessary use of pesticides because there simply isn’t a specific target area you can treat. Spraying around the exterior of the house has limited value because there are so many gaps accessible to the wasps. Although gable vents are often a point of vulnerability, soffit vents, some ridge vents and the gap between siding and the chimney are all well-traveled access points. The problem becomes one of how a homeowner can safely and effectively treat these difficult to reach areas.

Best advice

1) Keep a rolled-up newspaper handy. Yes, you can unload an entire aerosol can of pesticide on the beast but then what do you do about its sisters that are likely to show up? Plus, it’s not smart to be chasing a wasp around and spraying pesticides into the air—the same air you’re now rapidly inhaling after chasing the wasp around the house in your futile attempt to kill it.

Be patient; let it land and then smack it. Even that standard method of choice for many homeowners—setting off foggers in every room—won’t accomplish much either because any wasps that are not yet out in the open will not be affected by the chemical mist (whereas the fish in your aquarium are now floating at the water surface). However, if there are a significant number of wasps collecting in the attic (along with the cluster flies), then using a fogger may help reduce the wasp population up there, but may have no impact on the ones entering your living areas.

2) If you leave items like shoes on the floor or clothing hanging on a door, shake them before putting them on so you can see if a wasp flies out or if you dislodge the chewed remains of one mixed in with the hairball from your cat.

Expect to see this type of activity pick up significantly over the next five to seven days. As to the big question inquiring minds want answered, “When does it stop?” Your guess is as good as mine. We’re not into any real cold weather yet. As I said earlier, you can expect to see this activity, particularly indoors, even after periods of cold weather seems to have halted the outdoor wasp antics. But when the outside air temperature (and sun heating walls of homes) is adequate for activity to occur, you will see them both indoors and outside.

For more information about paper wasps, check out: http://insects.ncsu.edu/Urban/paperwasp.htm

Send your gardening questions or comments to: Brunswick County Master Gardener Column, P.O. Box 109, Bolivia, NC 28422, or call 253-2610. Enclose a self-addressed stamped envelope if requesting information or a reply. Answers may be printed in this column.