Green June beetle adults have been active for the past couple of weeks. They have a wide host range and, thus, can be attracted to many different kinds of plants when they are flowering or fruiting if these beetles are active. They can be attracted in considerable numbers, and these large numbers of highly visible beetles, often in a small area, are usually what causes concern. Every year, they seem to be more prevalent.
Relative to agricultural crops, they cause concern mostly in corn if it is silking when these beetles are active. They are often mistaken for Japanese beetles but are much larger and do not have the characteristic white tufts on either side of the abdomen as Japanese beetles have. They can feed on corn silks (Figure 1).
Green June beetles may cause concern because of their size and numbers in small field areas. Still, it usually only occurs on a few plants and not the whole field, and timing is everything because if this silk feeding occurs after the corn has pollinated, it does not affect yield or anything else. These beetles should be finished feeding on silks soon and fly off to other areas to deposit their eggs, and thus, this silk clipping will be forgotten with no ill effect on the corn.
Figure 1. Green June beetles feeding on corn silks. Photo by Cody Wyckoff, K-State Research and Entomology.
Amie Norton, Postdoctoral Fellow – Entomology
amien@ksu.edu
Jeff Whitworth, Extension Entomology Specialist
jwhitwor@ksu.edu