Japanese beetle #584034 - Ask Extension

Knowledgebase

Japanese beetle #584034

Asked July 27, 2019, 8:02 PM EDT

I just noticed a Japanese beetle infestation. What can I do to eradicate these pests

Denver County Colorado

Expert Response

Unfortunately, Japanese Beetles are here to stay and we only can learn strategies to manage them. For adult beetles on small plantings, flicking the insects into a container of soapy water will drown them. Doing this several times a day (morning and evening when they are least active) will begin to make a dent in the numbers because with fewer beetles munching on the plant, the plant itself will produce fewer chemicals that attract more beetles (ie. aggregation).

There also are a variety of chemical and bio-controls available. Read about them in this fact sheet https://extension.colostate.edu/topic-areas/insects/japanese-beetle-5-601/

Note that there are separate treatments to control JB larvae in the lawn - the larvae that will grow into next summer's adults. Also note that Japanese Beetles traps - which have become hugely popular and are sold at countless outlets - do not work to rid adult JB from your yard. In fact, the attractant in the trap attracts beetles and while some beetles are captured in the trap, many are not and those feed on surrounding plants which attract yet more beetles to your yard!
Gardening Help Replied August 01, 2019, 12:26 PM EDT

Loading ...