Most folks don’t see katydids because they are so well camouflaged. But anyone who sits on their porch on a late summer’s night are familiar with their “katy did….katy didn’t” song, along with their chirping cousin, the cricket.
True katydids are green with long thread-like antennae. They live in trees, bushes, and tall grass, and their color and body shape resembles a leaf for protection from predators. Their hind legs are long and powerful, making them strong jumpers. In fact, katydids usually don’t fly, but only flutter their wings to extend jumps. They are primarily plant eaters, although a few species feed on insects.
As mentioned earlier, katydids are great singers, or more correctly, instrumentalists. The chirping noise they make is produced (only at night) as the insect rubs its left forewing against a ridge on the right forewing. So katydids don’t sing, they sort of play a fiddle. And it’s the males who do all the fiddling, hoping to woo a female with his playing. She hears the chirping through ear structures called tympana, which oddly enough are located on their front legs.
Here in the mountains there’s a weather lore saying that the first frost of autumn will occur 90 days after the first katydid is heard. Based on that and my observation skills, first frost will be Oct. 10, so mark your calendar.
Because katydids are cold blooded, their chirping and other activities are closely related to temperature change. Listening to the length of the katydid’s song allows you to calculate the following temperatures: kay-tee-did-it (78 degrees); kay-tee-didn’t (74 degrees); kay-tee-did (70 degrees); kay-didn’t (66 degrees); kay-tee (62 degrees); and kay (58 degrees).
Steve Roark is the area forester in Tazewell, Tennessee, for the Tennessee Department of Agriculture, Forestry Division.