A number of beetles are known as 'June Bugs' and most of them get this designation for appearing in the month of June. Cotinis nitida is a large bronze and metallic green beetle that is often seen in June and July flying in low, lazy circles just a few inches above lawns or turf grass. They don't sting or bite and are not dangerous to humans, but they are not a 'nice bug'.
The adults are sometimes called 'Fig-eater Beetles' because they love the soft and easy to break skin of figs. They also like any soft fruit and can be quite destructive in peach orchards and berry patches. They use the small horn-like protrusion their foreheads to break the fruit's skin and then eat unsightly holes as they feed. Most of the time, folks can simply cut insect damage away from the fruit and use it, but these guys secrete a substance that permeates the fruit and makes the whole piece have a bad odor and taste. They're considered a minor pest in eastern North America and more so in the southern part of the U.S., even though they are pleasantly associated with summer, sweet tea and lazy afternoons in literature and lore. Those of us in the South consider them simply another part of summer. They make a bumbling drone as they fly similar to a bumblebee and generally appear when the summer has reached its peak. We do have a fondness for tradition here and they appear in poems, songs and stories throughout our reigon.
The grub or larval stage of the Cotinus nitida is considered a pest as well. The immature beetles are destructive to lawns and turf grass. These large white grubs do not actually eat the roots of the grass, but their burrowing habits undermine the root systems. They are easily identified because they do not use their legs to crawl. Instead, they turn on their backs and motivate with their tiny, useless legs in the air. They feed on decaying organic matter. If they become a destructive enough pest in your area Penn State recommends using Steinernema spp. and Heterorhabditis spp. as a non chemical means of control. These are insect-parasitic nematodes that infect the grubs and cause them to die. There is also a species of digger wasp that uses the grubs as food for their larvae, so let them go about their business if you see them working. There are chemical controls available as well, but as long as the insects are not causing extensive damage, I'd personally prefer for nature to take care of itself.
Some people may confuse these with another metallic green beetle...the dastardly Japanese Beetle, Popillia japonica. Japanese Beetles are far more destructive and are a non-native species. (Cotinis nitida is native to North America) It is easy to distinguish between the two. The Japanese Beetle is much smaller (about 1/2" long, 12.7mm) and has a series of white dots along the outside edges of its body. Cotinis nitida is a very large beetle (nearly 1", 90mm long) The image at left is a Japanese Beetle and it has a much different appearance than the June Beetle.
Cotinis nitida isn't usually present in enough numbers to be a serious threat to gardens or agriculture, however localized concentrations of the beetle might prove annoying and controls needed. I have them every summer and they can be seen flying their low, lazy circles above my yard. I have never felt it necessary to use any type of pest management on them though. They leave my apple trees alone and I've not noticed any damage to my grass. I have a "live and let live" philosophy and as long as they're doing no harm, I choose to do likewise.
Grub image courtesy of Wikimedia commons
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