|Photo Credit by Linda Langelo, CSU Extension, Golden Plains Area|
See any of this on your Austrian Pines? If you do then your pines might be attacked by Pine Zimmerman Moth. These moths which you may or may not see are about mid-sized moths with gray wings. Blended with red-brown and marked with zig zag lines.
This moth has a one year cycle. It overwinters underneath the bark in a cocoon. These caterpillars once active in mid-late April and May tunnel into any pre-existing wounds. As they start tunneling, you may notice sawdust and or pitch over the entry site. As they continue to feed into July and August, they create more pitch.
The adult moths are active in July and August and the female lays eggs near the previous masses of pitch. The best time to manage these moths are when the larvae are active and exposed on the bark. Trunk sprays are best in mid-April and again in August.