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Japanese Beetles in Greeley CO #938497

Asked July 08, 2026, 10:14 AM EDT

Hi there, I just watched my roses go from aphid-infested (yuck) to Japanese Beetle-infested (YUCK!!!!) in about 2 weeks. After having googled the beetles, I discovered that they are likely the reason my lawn ALSO looks terrible... My searches have led me to a product called Beetle Gone (Beetlegone.com). My question is: How safe is Beetle Gone to use? They do say it only affects beetle grubs (I would apply it to my grass to prevent later beetles), but in your expert opinions, IS IT SAFE FOR OTHER BUGS? I love gardening for my birds (and squirrels) and bees and other pollinators, so I'm extremely hesitant to use some kind of insecticide. I did pick the beetles off my roses last night and dunked them in soapy/bleach/water (GROSS!!!!!) and got about 30-40 of them. Please advise!!! Thank you!!!

Weld County Colorado

Expert Response

Hi Merry,

BeetleGONE! is safe for most other bugs. It affects Japanese beetle, other members of the scarab family (to which Japanese beetle belongs), and some weevils. 

https://www.inaturalist.org/observations?place_id=34&taxon_id=48201&view=species

This link shows those other scarabs. While there are many, most of these other beetles do not inhabit the same areas that Japanese beetle would be present. As such these other beetles are unlikely to be exposed to the beetleGONE! There are some other scarabs and weevils that infest lawns (masked chafers, oriental beetles, asiatic garden beetles, may/june beetles, bluegrass billbugs) that would be affected by beetleGONE!, but that effect would be desirable for anyone trying to maintain a lawn. 

While there is some risk to these closely related beetles, there is virtually no risk to other insects. The same applies to the birds, squirrels, and other animals. This is because beetleGONE! is not an insecticide in the conventional sense, it is biological insecticide. The product contains live colonies of a pathogenic bacteria. Like many insect pathogens, this bacteria is specialized to infect a narrow range of hosts. The physiology of other insects (and other animals) is too foreign to this bacteria for it to be able to infect them. 

And while it is possible that Japanese beetle are responsible for your turf dieback, we can't be certain merely from the presence of the adult beetles nearby. Even the presence of a few Japanese beetle larvae in the lawn is not enough to warrant treatment, as the treatment threshold is 6-8 larvae per square foot. 

Most of the lawns I've evaluated this season were being affected by poor irrigation coverage. I'm not saying that is the definitive issue with your lawn either, but I would encourage you to consult your local extension agent (or me) about your lawn before spending time, energy and money on treatment. If Japanese beetle larvae are responsible for your turf dieback, there is a granular formulation of this same bacteria (grubGONE!) that can be applied to lawns. 

An Ask Extension Expert Replied July 08, 2026, 1:03 PM EDT

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