Yes, Milky Spore works against June beetles, as well as Japanese Beetles. Please know that Milky Spore is not effective in every soil type, nor every climate. Call your local extension office for regional information. If it IS something that can be helpful in your area, they will know the best timing of the application, as well.

A couple of years or more ago, we had a bad outbreak of Japanese Beetles and used Surround WP, a kaolin clay product used to repel many different kinds of plant feeding pests. It worked like a charm.

This year, we've had hoards of both June beetles AND Japanese Beetles and have used the Surround WP again with great success. Since our beetle season is of pretty short duration, we'll probably only have to apply it twice. It does last through some rain.

This product does not kill the beetles (and other feeding insects), but encourages them to go elsewhere. It is approved for Certified Organic growers of all kinds of crops (including fruit, veggies, herbs, etc.)

Another products I've used with some success with plant feeding pests is Neem oil. It not only acts as an anti-feedant but has growth regulator properties when ingested. Little collateral damage to beneficial insects when used according to label directions.