Have you tried using Milky spore for those pesky beetles? I did. It may take a year or two to make a huge difference, as the product takes out the emerging white grubs that come from the eggs that they lay. The Grubs actually become more of the solution as they produce more of the spore, and as the grubs move around they extend the area of coverage.
It will take a year or two for the grub population to really reduce a lot. 3 years in, and I am not seeing any near the red raspberries anymore.
Once using this product you no longer use the instant or quick kill products. That would defeat the Milky spores effectiveness.
They claim results can last more that 10 years.