National Moth Week

There’s mothing to do.

~from Nature Conservancy promotional article on National Moth Week

It is, indeed, the third annual National Moth Week (July 19-27, 2014). National Moth Week’s main goal is to promote awareness of moths, and to encourage people to observe and report their findings on this fascinating and little known (to most of us) group of insects. More information can be found on their web site at So, in honor of this event, I thought I would do a couple of posts this week on moths and their caterpillars.

C arpentorworm Moth with finger for size comparison

Carpenterworm Moth on oak stump (click photos to enlarge)

A few weeks ago, a large oak out front had to be taken down because it was showing signs of imminent death – the bark splitting off, a large dead limb hanging out over the driveway, and sap oozing from some cracks near the base. One evening as I walked by the stump, I saw a large gray moth sitting on top. I wasn’t sure what it was, but then noticed something laying on the ground below.

C arpentorworm Moth pupal skin

Carpenterworm Moth pupal skin

It was a large brown pupal skin that I recognized. I had seen these once before, but instead of lying on the ground, they were sticking out of holes at right angles to the trunk of a large oak. I had identified them then as the pupal sheds of a Carpenterworm Moth, and now I had found a live adult.

C arpentorworm Moth on bark

A Carpenterworm Moth blends in with the colors of tree bark

It was probably lucky that this moth had crawled up to the recently cut surface of the stump, as I might otherwise have missed it. Their camouflaged coloration helps them blend nicely with the patterns of tree bark.

C arpentorworm Moth head on

Carpenterworm Moth view head on

I believe this specimen was a female – they are larger than the males and lighter gray in color overall. She was close to 2 inches in length and must have just recently emerged as she allowed me to pick her up without taking flight.

C arpentorworm Moth on finger

Female Carpenterworm Moth

These moths are quite large, despite being members of the so-called Micromoth family. After looking in some field guides and online, I think this one is called Robin’s Carpenterworm, Prionoxystus robiniae.

C arpentorworm Moth and pupal skin

Carpenterworm Moth and pupal skin

The larvae bore into the trunks of various hardwoods, creating large tunnels. They require up to 4 years to complete their life cycle. I still have never seen a larvae, but they must be quite large given the size of the pupal case and the resulting moth.

This is just one of the thousands of fascinating species of moths you might encounter here in North Carolina. Leave a porch light on or look for National Moth Week events in your area, and get outside to learn about this amazing and beautiful group of insects.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s