The Beetles are Back

After that long, cold winter, this warm weather is wonderful!  In no way, shape or form and I ready for it to turn off cold again.  However, all of this sunshine and warm temperatures does bring on a whole set of problems; insects being at the top of that list.  I am starting to receive several phone calls about our “dear friend” the Japanese Beetle; meaning it is inevitably that time of year again.  The Japanese Beetles are emerging and making their presence known.  Individual beetles live for about 5 weeks; the season usually lasts for 6 to 8 weeks, peaking in mid-July.

According to Lee Townsend, UK Entomology Extension Specialist, many insecticides are labeled for use against adult Japanese beetles, if control is needed. Pyrethroid products such as cyfluthrin, bifenthrin, deltamethrin, l-cyhalothrin, and permethrin can provide about 2 weeks of residual protection. Carbaryl can give 5 to 7 days of control, however these products are toxic to bees and repeated applications can contribute to spider mite infestations.

Botanical alternatives, such as neem or pyrethrins, can give short-term protection from light to moderate beetle pressure. Insecticidal soap; extracts of garlic, hot pepper, or orange peels; and companion planting, however, are generally ineffective.

If your beetle population is not that significant, then you can always pull them off plants one by and one and terminate them.  Continued physical removal of beetles or use of protective netting will help to minimize damage when beetles are not numerous. Individual beetles do not eat much, but if undisturbed, more will arrive and damage will intensify.

Treat foliage thoroughly and repeat as needed to prevent re-infestation during the adult flight period. Follow label directions and avoid spraying under windy conditions or when bees are foraging. Be sure the insecticide is registered for use on the plant or crop you intend to spray. If it is a food crop, note the minimum number of days that must be observed between the date of the last application and the date of harvest.

Japanese beetle traps will attract more beetles than they capture and are likely to result in more damage than if they were not present.

For more information about controlling Japanese Beetles and other insects, contact the McLean County Cooperative Extension Service at (270)273-3690.  Educational programs of the Cooperative Extension Service serve all people regardless of race, color, age, sex, religion, disability or national origin.