Potato leafhoppers are present in large numbers in southern Illinois. Be watchful for their presence and early damage on red maple, red bud, hop tree, sugar maple, winged euonymus (burning bush), wisteria, and other woody ornamentals. Early infestation can be detected by using an insect net to sweep under and outward along the tree or shrub branches. The 1/8-inch-long, wedge-shaped, green potato leafhoppers will be caught in the net. A method for determining whether potato leafhoppers are in the area is to check lighted windows at night for their presence. Applications of a pyrethroid or other labeled insecticide provide effective control.
Caterpillar hunters are being found in southern Illinois. These are flattened, widened, adult ground beetles in the genus Calosoma that are about 1 inch long. Several species occur in Illinois that are metallic green, purple, or black and are attracted to lights at night. They were numerous in parking lots and other areas lit at night last year. Many people asked about them due to their large size and noticeable color. Caterpillar hunters climb trees to feed on caterpillars. The species that we have are a combination of native species and those imported decades ago to control gypsy moth caterpillars. They are considered beneficial, and no control should be needed.