Pest Identification And Information

Over Wintering Pests

There is no doubt about it; insect activity is greatly if not completely reduced during the winter months of November through February.  There are many changes that occur to the environment that cause this change in insect activity. The most obvious is the gradual reduction in temperature along with the shorter hours of sunlight and the dormancy of trees and vegetation (which are food sources), and you have an environment not suited for much insect activity.

In the winter inside your home, it is a warm environment with food sources for many types of insects. Insect populations can flourish and grow in your home and will require professional help to monitor and control these pests, as well as determine a prevention strategy for next fall.

In the heated or warmer areas of structures where pests have overwintered it is possible to see live insect activity. Obviously any insects noted indoors during the winter are not coming in from the outside; they are coming from the structure.

The following are some examples of pests that over winter in structures:

Boxelder Bugs

Boxelder bugs will over winter in structures in large numbers. During the warm weather months they live outdoors feeding on the seeds of the boxelder trees.  They usually aren’t a problem until the early Fall when the trees start to go dormant.  They can usually be seen during warm fall days, clustered in large numbers along the South and West walls of structures.  At night they go into the cracks and crevices around doors, windows, under siding etc.  Once the outside temperature gets cold enough they will go fully dormant inside the walls. However, on warm sunny days during the Winter the sun will heat up the South and West walls and the boxelder bugs will “wake” up but the air temperature outside is too cold so they move toward warm areas inside. There is no food for them and no reproduction is occurring at this time.  They are just active due to the heat from the sun.  During warm days in the Spring the boxelder bugs again will be seen clustered outside on the South and West walls, once the weather warms up, the trees start budding and producing seeds the boxelder bugs will leave the house for the summer.

Cluster Flies

Cluster Flies do just that - they cluster together to try to stay warm over the winter.  They can invade houses by the hundreds or thousands and will emerge all winter long on warm days.  Office buildings with poorly sealed parapets can get this problem as well, especially on the South and West sides.

Ladybugs or Lady Beetles

Asian Lady Beetles have been on the rise and seem the be the predominant "Lady Bug" invading     houses these days.  While generally consider beneficial to the environment, they are not considered beneficial in our homes.  Some houses can get them by the dozens, hundreds, or even houses.  There are many different looking ladybugs, and even the Asian Lady Beetle can vary, but look for the distinctive "M" marking on the head of the Asian Lady Beetle. Their distinctive odor is often a problem for homeowners with allergies.

TREATMENT

Many of these insects can be controlled by sealing up your house with the appropriate caulk or sealant.  Where this is not feasible, consider a timely application with a liquid residual in the fall, particularly on the South and West sides of your house where insects head in the early evening for the heat that is retained as the sun sets.  Typically one application will be needed, usually in late August, however if we have an extended summer, the treatment may have worn off and another may be needed in late September.

If any of these pests make it indoors, simply use a vacuum to remove them.  Often indoor treatments are not needed as these pests will die naturally.

OTHER WINTER PESTS

Ants

It is very common to see ants during the winter.  Typically structures that are built on slab foundations (no basement) are the worst offenders.  The ground does not freeze under the slab, the slab “floats” on about 6-10 inches of sand, and often the heat ducts, water/plumbing lines and other utilities will run under the slab, thus allowing ants to enter the interior areas of the structure.  Over time small cracks will develop in the slab due to its “floating” and the swelling/shrinking caused by the freeze/thaw cycle thereby allowing ants easy access to the interior.

Carpenter Ants

Satellite colonies of carpenter ants that have nested within the warm areas and wall voids of structures will still go into a dormant state during the winter even though it’s relatively warm where they’ve nested.  They will however, come out of dormancy usually in mid January and will be seen around water sources.  They are not fully active at this time, as the main or parent colony is almost always in a tree outside, where it is cold and the queen and workers in the main colony will remain dormant until spring.  There are no queens, eggs nor any reproduction in the satellite colonies.

Spiders

Spiders that over winter in warm areas of structures can be active all through the winter season.  Spiders tend to enter structures when it gets cold out if they can since their food supply is also going inside for the winter.

Mice

Mice can enter a structure at any time but in our climate they do enter more often in the fall as the weather changes and your home is an attractive home for them during the cold winter months.  Many times they are not noticed right away and actually nest within the structure, reproduce, and then are noticed as the population gets too large for the initial nesting area.  Because of the damage and ability to spread disease, it is far better to protect your structure and prevent them from getting entry in the first place.  For those areas where you cannot prevent entry, consider placing rodent equipment to stop them from getting established.  An ounce of prevention is worth a pound of cure.