Lots of insects visit flowers late in summer. Some are gathering pollen and nectar, but others are feeding on flower structures.
12-Spotted Cucumber Beetle
One example from the destructive group is the 12-spotted cucumber beetle (Figure 1). This insect spends the winter as an adult, so it feeds a lot before moving to a protected site for the cold months. It chews relatively round, smooth-edged holes. However, this insect is usually not around when the damage is discovered because it moves frequently to visit flowers of many different plant species, especially Chrysanthemum.. Many Insecticides labeled for flowers can provide protection against this and other flower feeders.
The Scolia wasp is among the beneficial insects visiting flowers now. This distinctive half-inch-long wasp with blue-black wings has a reddish tail and two yellow bars near the end of the abdomen (Figure 2). It is a natural enemy of Japanese beetle and green June beetle grubs.
These wasps can be seen cruising over grassy areas where grubs are present. They will enter the soil and burrow to find beetle larvae, sting them, and then lay an egg. The wasp larva uses the grub for food and spends the winter in a cocoon within the host, emerging the following year. The wasps are not aggressive and do not pose a threat. Nectar provides them with an energy source that allows them to search for prey.
By Lee Townsend, Extension Entomologist