Treatments Available for a Western Conifer Seed Bug Infestation

Western conifer seed bugs are unique-looking insects originally observed in the western United States that earned them their name. These bugs feed on immature cones and seeds of different species of hybrid trees and conifers.

After some time, the bugs spread much further to the east and you can now see them in Maryland and Pennsylvania. Despite not being outright harmful, these bugs can become an annoyance once they sneak indoors.

What Do These Bugs Look Like?

An adult western conifer seed bug Leptoglossus Occidentalis has a length of ¾ inch and has a reddish brown colour. On its abdomen on the upper side is a prominent orange, white or yellow and black pattern. These bugs also produce a loud buzzing sound when flying. Most people confuse the western conifer seed bugs for the skinny stink bugs because of their similar appearance.

Life Cycle

Western conifer seed bugs can enter your home in the fall through cracks and gaps seeking protection from the colder temperatures. Once spring comes, they go back outside to feed on developing flowers and seeds of coniferous trees such as spruce, hemlock, red pine, and white pine.

The female seed bugs lay rows of eggs on needles, with these eggs hatching in around 10 days. The nymphs feed on cone scales and needles on occasion. These nymphs pass through five developmental stages and reach their adult phase by late August. This is also that time of the year when the bugs start looking for sites where they overwinter.

Possible Treatments for Infestations

Even expensive and aggressive insecticide applications might not be effective since it is almost impossible to treat all hidden areas that might harbour these insects. Make sure you seal cracks around light fixtures, switches, and electrical outlet boxes as well as around baseboard and window moulding on inside walls to trap these bugs inside the walls.

For older houses with double-hung windows that have pulleys, these insects often enter living spaces through the opening in the pulleys. You can apply masking tape over this opening to close off these potential entry points for these insects. Do these in both windows and doors.

A vacuum cleaner is also an effective method to remove the slow-moving and slug bugs around the house.  You can spray outside walls of your home, specifically the walls that face west and south, using long-lasting insecticides that have been registered for this specific use.

Do this in the month of September to help decrease the number of seed bugs entering homes. You have to apply these sprays once you first notice these bugs gathering on outside walls.

Prior to treating your entire house, make sure you spray a small test area first to check that the insecticide doesn’t stain the paint or siding. Make sure you read and follow every direction on the product label. Of course, you will spray above your head when you spray outside your home. Don’t forget to wear protective pieces of clothing like a raincoat or wide-brimmed hat. It is also a must to wear eye goggles.

Other Helpful Tips for Treating Infestations of Western Conifer Seed Bugs

Check out other steps you can do in advance of the fall and winter migration of seed bugs.

  • Install thresholds or sweeps at the base of doors if you don’t have them yet. Never forget your garage door so ensure that it is sealed tightly as well. Caulk around door and window frames.
  • Screen vents as well as other huge openings to the outside that cannot be filled or caulked.
  • Caulk on outside if there are pipes or utility lines entering the house. Fill openings around the lines where the bugs can gain entry. Caulk underwood fascia and around chimneys.
  • The window air conditioning unit is among the main entry points people tend to overlook. Remove the window unit once you are comfortable for the fall season and seal or tape the opening.
Outdoors, plan on your annual fall yard cleanup, specific around your home’s perimeter. The true bug hides under piles of mulch or leaves, debris, and under boards. Store your firewood away from your home. Achieve successful pest control and lessen the number of these bugs by getting rid of hiding spots around your house.