Wednesday, September 1, 2010


I spent much of my preteen life in more urban environments. Most of my fellow urban residents were intolerant of any creature they didn’t understand, which seemed to include just about the entire animal kingdom. One of the most hated of the wild life forms was the Bagworm. The sight of these silken bags hanging from the shrubbery could illicit all manner of strange behavior from the local homeowners. For me, the bags meant money, because I was a professional picker and could earn up to five cents a pound for bagworms removed from the bushes.

The bags provide camouflage and protection to a moth larva and are formed of silk and adorned with bits of plant material. The larvae carry the bags along as they feed. They usually don’t become noticeable until late in the summer when they’ve reached their maximum size.

I remember people having all sorts of theories as to what was actually inside the bag. I watched adults stand and argue their points, all while bags hung just a few feet away. I found it curious that they didn’t do what I had done and opened a bag to see. This moth larva is sealing the bottom of the bag with silk in preparation of pupating.

When you live your life hidden inside a bag, you don’t need anything in the way of fancy adornment. The large larvae are generally those of the females. They will emerge from their pupae as wingless adults that will never leave their bags. Males will visit the bags to fertilize the females and then the females will lay their eggs and die within the bags.

During its mobile period, the larva uses its true legs for locomotion. The prolegs serve to help keep the bag in place around the body. Even though this larva maintains a silken lifeline to its home, it could never find its way back to the bag.

The bag is just like a cocoon and most cocoons are easy to put back together. As a child I used to open cocoons all the time and then repair them and wait for the adult moth to emerge. The trick to success is to avoid blocking the point of emergence, or if this is indeed a female, the access point for the male. I hung this one from a shelf of the bookcase on my desk and will wait to see what happens.


  1. Hi Steve..I have seen those but was not wanting to find out what was in there ...fear of the unknown!! ; }
    Do you know what kind of a moth it is or are you just waiting to see!!
    God bless your wife...see must be a saint!! ; }
    I hope you keep the door to that room closed tight!!

  2. grammie g - The moth is called a Bagworm Moth. It's not much to look at, but if I get a picture, I'll be sure to post it.
    I'm pretty good at keeping in-the-house animals under control and usually capture escapees before anyone else knows they're loose. Usually my wife is exceptionally tolerant of my activities.