June bugs how to get rid of them

Asked October 2, 2014, 6:18 PM EDT

This summer I had lots of large June Bugs on my peach tree.

I also lost a lot of grass which from research online it seemed it was from the larvae eating the grass roots in the lawn. What do you advise I use to get rid of the larvae so I can have grass again. I also have two cats and birds visit my trees. If necessary, I would use an insecticide. I have googled and most sites recommend Sevin. Do you agree?


Sheila Pugach

Bernalillo County New Mexico

3 Responses

Hi Sheila,

There quite a few reasons why your grass could be losing it's vigor, so first we should start with verifying that "white grubs", the larvae of June beetles, are the cause of the decline of your grass. If they are, killing the adults that you see on your peach tree is not an effective approach.

To check for them, look for loose turf that shifts on the surface of the soil like a rug, or dig the perimeter of dead areas in your lawn and screen some of the soil underneath. Left in the screen after the soil passes through, should be some white C-shaped grubs with legs. These are what are feeding on your roots. Submitting a sample of the grubs you find for I.D. might help with the timing of control measures, as different species have different lifecycles.

Assuming that white grubs are the problem, and given that we are already into the end of October, now would not be an effective time to treat. Late fall, leading into spring, the larvae are larger, have moved lower into the soil profile, and are hard to affect with insecticides. This is unfortunate, because this time period is normally when the larvae are large eating machines and damage becomes great enough to get noticed by most people. For this fall and spring, you will have to tolerate the damage. For next summer, when the grubs are still small, you can use any product labeled for white grubs with the active ingredient imidicloprid in it (for example, Merit), or you can use something with the active ingredient carbaryl in it (for example, Sevin). Apply in August/September and follow the label exactly. Application of insect parasitic nematodes of the genus Heterorhabditis (for example HeteroMask, Grub-Away, and others available from mail order suppliers) can also be effective if applied correctly during the right conditions, although more research is needed on this method of treatment.

The depth of the thatch layer on your lawn can influence the ability of the insecticides to reach the grubs in the soil. If too thick (greater than ¾-1”), insecticides can bind to the organic matter in the thatch. Aerating can increase the effectiveness of insecticides by helping it reach the soil better directly, as well as by encouraging beneficial microbial activity that decreases depth of the thatch layer. Aeration can also have the benefit of mechanically damaging the grubs. Watering well the day prior to aeration will bring grubs closer to the surface to be damaged during aeration. If you have a cool season grass, you might be able to squeeze in an aeration now, or you can wait until spring. If you have a warm season grass, aerate in the spring or summer to improve lawn health, improve effectiveness of applied insecticides, and damage grubs at a time when they remain unaffected by chemicals.

You need to fix your website as I thought I was writing to an extension expert and one would answer me for my area. There was no Bernalillo County specific site on the web page. People waste their time trying to contact you and you need to walk through the website and see what users encounter.

Sheila Pugach


Dear Sheila,

I'm sorry if we do not currently have an answer for your question. Writers for this site volunteer their services, so we may not always have an expert for specific issues in every region. However, you can contact your local extension agency at http://aces.nmsu.edu/directory/index.php?staff_search_action=dept&criteria=30.