Caterpillars in the Parsley

When you plant a garden you often end up feeding the critters more than yourself. So rather than get too mad about this and spray dangerous chemicals, why not enjoy the experience and observe the intriguing lives of the beings that are harvesting your plants?

Upon starting to pick some parsley, our grandson Simon noticed some very interesting caterpillars (see photos). Now when you observe caterpillars on members of the carrot family (Apiacae or what used to be Umbelliferae) such as parsley, fennel or dill, you should immediately suspect that the caterpillars may be black swallowtails, which they are in this case. The larger and brighter caterpillar is in the final process of molting, which is necessary as they grow so rapidly. After this molt it turned around and ate the shed skin – presumably to regain the nutrients contained.

The older caterpillars are very handsome, but you may wonder why they look so different at different ages. The younger, early instar caterpillars are said to resemble bird droppings as a means of camouflage. With more maturity the brighter colors might be seen as disruptive and a partial camouflage. But the older caterpillars have a means of defense by extruding an orange tongue-like organ (osmeterium – see photo taken after I squeezed the caterpillar) and raising the anterior end of the body. Birds, lizards or frogs as predators may be frightened by the odd almost snake-like appearance produced by this strange organ. It is interesting that two very different colorations are used by the same species during development- is this an attempt to fool predators by changing the search image so necessary to find prey?

I have also attached a photo of an adult black swallowtail that just emerged from a chrysalis, after feeding on fennel in a friend’s garden (Abbie Banks) in Florida.

So consider your gardens a golden opportunity to gain ecological knowledge as well as a meal. You can in essence harvest the information, “feast” on this intellectually, and maybe get more enjoyment than from the food itself?

Bill Dunson, Englewood, FL & Galax, VA
wdunson@comcast.net