CONCORD – We all have memories of the summers of our childhood. The sun rose early, the days were long, and we could play outside until dark. But, of all my summer memories, my most cherished is of the time I spent with my Uncle Dan at the Catawba Worm Tree.
For several weeks in early summer, Uncle Dan and I met each morning at the tree; first to see if there were worm eggs, and then to wait for them to hatch.
Now that the eggs had hatched I worried if Uncle Dan would still come to the tree each morning. I waited on the front porch hoping to see him walking down the driveway to the tree. When I did, I was overjoyed and rushed out to join him.
“Let’s see how our worms are doing today.”
I smiled inside. He had said, “Our worms.”
When the caterpillars first hatched they stayed close together, in a group. Their first meal was their egg case and then the natal Catawba leaf. They used their strong, razor like mandibles to cut pieces of leaves to eat, moving forward, resembling a regiment of soldiers. In their wake they were leaving behind only “skeletonized” leaves.
“There will be plenty of worms if the birds and the bugs don’t get them. But they still have a long way to go before they’re good fishing worms. We’ll keep an eye on them.”
I was happy to know they were not ready to be fishing worms.
The next morning when Uncle Dan turned over the leaves the group of worms was not there. I felt my heart sink – had the birds and bugs gotten them?
Uncle Dan continued to examine leaves and, to my relief, pointed to a caterpillar and then another. The caterpillars had abandoned their group, becoming solitary, crawling in search of their own leaves to feed upon.
For the next several days the caterpillars ate voraciously, traveling upwards into the tree, leaving behind only raggedy leaves, stems, and veins.
One morning the worms were not moving or eating.
I felt heartsick and whispered, “Are they dead?”
“No. When they start acting this way they are getting ready to shed their skin. Look! This one is starting now.”
Uncle Dan gently plucked the leaf holding the caterpillar from the tree so that we could see it shed.
Watching this creature up close was mesmerizing. I was torn between wanting to watch and feeling compelled to look away. A shiver of excitement, a “frisson,” spread over me.
For the next half hour, I was completely unaware of time as I watched this wondrous process.
“Do you think it hurts him to lose his skin?”
“I don’t think so; he’s just outgrown it.”
When a caterpillar sheds its skin, the process is called molting. The stage between each molt is described by a beautiful word: “instar.”
Uncle Dan and I were watching what would be the second instar; the first instar had occurred when the caterpillars hatched. The Catawba worms would undergo five instars on their journey to adulthood.
Before a molt, the caterpillar is completely inactive for several hours. Then, the caterpillar begins to contract. The head plate splits and falls away. Through a series of rippling, wave-like movements, the caterpillar uses 4,000 muscles to twist, squirm and wiggle, working its way out of the tight, old skin, the act resembling the shedding of a sock.
As caterpillars grow, their skin cannot grow with them. To increase in size, it develops a new, larger skin underneath the current skin. When the caterpillar has eaten all that its current skin can hold, it molts the old skin, and the newer, larger skin underneath is revealed.
After molting, the caterpillar’s skin is very soft. While the new skin is soft, they swallow a lot of air, which expands their body. When the new skin hardens, they let the air out and have room for growth. With a larger skin, the caterpillar is once again able to feed. Its first meal is the recently discarded nutrient-rich skin.
After eating the old skin, the caterpillar began to nonchalantly nibble on the leaf I had been holding. I reluctantly handed the leaf and the caterpillar back to Uncle Dan, not wanting this time to end. He gently guided the worm onto a fresh leaf to feast upon.
My Uncle Dan and I then stood side by side in reverent silence for a few moments, watching the worm take its place in the tree. We knew we had just shared a remarkable wonder of nature together.
Editor’s note: This article was contributed by Cindy Austin, a new addition to the talented team of writers at the Richmond Observer.
