Can't Wait for Spring

May is only a week away, however April is proving cold and wet in Nebraska this year.  However, this hasn't stopped us from finding insects in our world.  Despite the temperature hovering around freezing, and a cold rain falling; we pulled on our rain gear and went outside to collect some insects.

One of the most important characteristics that make insects such fantastic teaching tools is their availability.  Although it was cold and raining, you can still find insects in your environment.  This post is focusing on a garden pest, commonly called the bagworm moth. These critters are members of the Psychidae family.  They are moths, not worms as their common name may imply. They are plentiful in suburban and urban setting in the eastern United States, as far west as Texas and Nebraska, as far north as Massachusetts, and as far south as Florida.

At first, it may be tricky to find these little critters, they are an excellent example of camouflage.  Can you see how the outside of the casing is covered with bits of the host plant, including needles and branches?  Notice how it is attached to the arborvitae? There is a shiny, very strong piece of silk that attaches to the host plant, called a cremaster. Wiggle the branch, or better yet, have your child wiggle the branch and watch how the silk acts like a pendulum, allowing the casing to move freely with the wind. Often, the silk will be covered with a type of insecticide, to prevent predators from climbing down and attacking the casing. 

In hunting small game, it's easy to miss something you are not looking for. So, to increase your odds, first look for a common host plant. In this case, bagworm moths enjoy evergreens. After you find some evergreens, look for some dead spots or patches of the plant where the leaves or needles have been stripped. You will often find an insect responsible for plant damage, so spotting brown leaves/needles is a good point to start your investigation. I've included a picture of typical damage from the bagworm moth.

When collecting any type of casing or cocoon, it's best to take as much of the foliage as possible - more on this later.  James was more than happy to hold the basket and catch the falling casings. Older children would probably enjoy clipping the branches, too.

While we were outside, we collected a couple of sticks to provide some height to hang the casings on. I am using a critter container, which usually run around $10 at a pet supply store.

Here is another view of the casing and the amount of plant material I collected.

Notice how I used the sticks at an angle to provide height for hanging? These casings look a lot like a chrysalis that a caterpillar would make before emerging as a butterfly or a moth.  In this particular case, the casing is not actually a chrysalis, i.e. no moth with wings is going to emerge from this case. Adult, female bagworm moths do not have wings.  They look a lot like a grub, and each one lives in one of these casings. During the summer, you may notice them hanging from a strand of silk from the tree.  The female is probably dead right now, but inside of her are hundreds of eggs that will hatch and emerge in the spring. If a large butterfly was going to emerge, it is very important to provide them with an area to hang and stretch their wings.

 Anyways, the point is, you DO NOT have to know what will emerge to have this be a meaningful entomological experiment.  In fact, not knowing what will hatch can be half of the fun! I wanted to mention this point because if you don't know what will emerge, its best to prepare for a huge butterfly, and give them plenty of vertical and horizontal space to spread their wings. This activity is a great way to speed up the arrival of spring, if you are just as impatient as we are!  Because it is warmer in the house than outside, we should have some emerging bagworm moths very soon! Hopefully, we will have more pictures to post soon!