Conifer seed bugs  are a common fall and winter nuisance in homes. They are fairly large insects (about 5/8 to 3/4 inch long) and look rather bizarre. They fly readily and can produce an odd, somewhat piney odor when provoked. These behaviors can alarm homeowners. However, conifer seed bugs are harmless.

Members of the leaffooted bug family, they eat seeds and do not bite people. They enter homes in search of warm, protected sites to overwinter. They do not reproduce in the home or damage household items. Conifer seed bugs usually die in a week or two if not allowed to drink water.

Conifer seed bugs primarily feed and develop on seeds of various trees and shrubs. They prefer pines, Douglas-fir and other conifers but feed on developing seeds and fruits of a wide variety of plants, including dogwood and sumac.

The insects overwinter as adults under protective debris and other shelter. Frequently, they move into nearby homes where they may cause concern. However, during the cool season they are semidormant. They neither reproduce nor feed, but rather live off fat reserves.

In spring, the insects move to trees and feed on male flowers and year-old cones. Beginning in late May, females lay eggs glued in small groups to needles and leaves. The immature or nymph stages somewhat resemble wingless adults. Nymphs feed on the seeds through the summer. They become mature in August and September. Adults continue to feed on cones until they move to winter shelter. There is only one generation per year.