Most common in the southern parts of Sweden. They are also found on the west coast. The colour of the body is greyish brown with two light stripes on the wings. It's mostly the warmer places in the house that gets infested like the ceiling or southern outer walls and eggs can be found in cracks. They attack spruce but never leafy trees. In temperatures between 25-28 degrees the caterpillars keep very active, below 12 degrees there is no activity.
How to avoid them:
- Professional inspection
Suitable treatments: chemical treatment or gassing.