Nature Notes

Written by Tolly Beck
Tolly Beck is the horticulturist at Lasdon Park and Arboretum in Westchester County. She was formerly a horticulture educator for New York Botanical Gardens in the Bronx and Cornell Cooperative Extension of Rockland, NY.

Nature Notes
Stinging Caterpillars

   Folks have been spending more time outside now that the oppressive heat and humidity is starting to wane. We are well aware of the painful stings of bees, yellow jackets, hornets and wasps. What may come as a surprise is the number of stinging caterpillars currently on trees, shrubs and perennials.    

The stinging caterpillar that I have been encountering often in the gardens is the saddle back caterpillar. They deliver a surprisingly painful sting. This caterpillar has sharp rigid stinging spines that are located in small bunches at the front and back of the body as well as along the sides. The saddle back caterpillar is most often seen in late summer and fall and is the larva of a small and furry shiny brown cup moth.  

 Saddleback caterpillars are beautifully colored, but appearances can be deceiving. In the natural world, predators usually know to stay away from brightly colored insects as they are often toxic. This warning coloration works for monarch butterflies that are not toxic to humans but are toxic to predators.

   Reactions to the sting from the saddleback caterpillar may be quite severe for people who have allergies and/or sensitive skin. If you are stung you may get some relief by applying adhesive tape sticky side down to the area of your skin that came in contact with the stinging hairs. The stinging or burning sensation is usually not long lasting. 

   Saddleback caterpillars are found on the foliage of woody plants and perennials. Lately I’ve been finding them on daylily foliage as I remove the brown dried leaves from the plant. If you see one be sure to look at it, but don’t touch it. Some things in nature are just meant to be admired from afar.