NWF® The Backyard NaturalistTM

Wednesday, November 08, 2006

Killer Frost and Found Caterpillars



The past week's weather dealt our vegetable gardens and Backyard Wildlife Habitat that shock and schedule-adjustor known as the "first killing frost." Gone are the tomatoes, peppers, marigolds and okra. The early morning air went well beyond frost to freeze. What had been sweet basil and tropical milkweed is now mush as the thermometer registered its first of the season 20 degree F. reading.

This event is both dreaded and eagerly anticipated. Such is gardening schizophrenia. Summer's gardens linger, looking rattier with every early morning brush with frost. When the juncos and white-throated sparrows que up at the feeders, they tell me the winter is approaching even if I am more elated at finding that last bunch of green beans or the final cuke of the garden season.

I don't want to give up the last fresh basil. Discovered dozens of cherry tomatoes postpone the first purchase of marginally edible store-bought tomatoes. There is joy however in accepting what is inevitable (well, ok, it's not inevitable given the warming climate, lateness of recent killer frosts and the seasonal paucity of snow), and I can then move ahead with clean up, mulching, planting of a winter cover crop and other chores postponed until IT, the killer frost, occurs.

Dill has become the garden's most welcome weed. It is frost-hardy, showing little effect from the first big freeze. It is tasty as leaf and seed. It returns year after year with no effort on my part. The blooms attract small pollinating flies, bees and wasps. Most notably, it is the home of dozens of black swallowtail caterpillars over the course of the year's two or three generations of this exotic plant. After this frost, the swallowtail "cats" reappeared for perhaps the last feeding before their final molt and overwintering as pupae.

One other much larger caterpillar appeared during these last days of summer-like weather. I carefully picked up and then carried the large green insect dotted with red on my shoulder. It crawled down my shirt sleeve before exiting in suitable habitat. Although assuring myself that it would likely be better off wandering through tree-edge meadows and forming its cocoon on its schedule, I had hoped to photograph it.

The following day, returning to the locality where it had left me, I found it again wandering off to construct its overwintering shelter. I once more grabbed it, placed it in my lunch bowel, snapped its photo, above, in very unchararcteristic habitat, and then immediatley released it.

This large, late caterpillar will emerge next April or May as a beautiful, lime green luna moth.