European Chafer Beetle and GrubEx

Asked June 18, 2018, 1:46 PM EDT

I have seen about 6 European Chafer Beetles in my pool in the past few days. Is it to late to apply GrubEx? I do not want to kill anything but the Chafer Beetle grub and do not want to apply insecticide that will not hit my target.

Wayne County Michigan lawns and turf insect issues

1 Response

Good afternoon and thank you for using Ask an Expert. Controlling Chafer beetles can be an on going job. I am sending some information on the timeline of controlling the grubs which will control the beetles.

A summary for successful grub control

Grubs in turf

  • Check the bag or bottle to determine what active ingredient the product contains.
  • Do not use products containing ONLY lambda-cyhalothrin, gamma-cyhalothrin, bifenthrin, deltamethrin, cyfluthrin or permethrin for any phase of grub control.
  • Do not use preventive compounds such as clothianidin, thiamethoxam or imidacloprid now. Use them in June or July to control grubs that would be damaging turf in the fall. Applying them now will allow some of the chemical to leach through the turf or break down to the point that not enough insecticide will be there in July to control grubs.
  • The preventive compound chlorantraniliprole should ideally be applied in April or May to control grubs that would be damaging turf in the fall as it will take longer for the material to move to where the grubs will be feeding in July.
  • To kill grubs in the spring or fall, use carbaryl or trichlorfon.
  • Always wear rubber gloves and rubber boots when applying insecticides to turfgrass.
  • Make sure to irrigate the lawn with at least 0.5 inches of water* and allow the grass to dry before allowing anyone or pets into the treated area. Irrigation is essential for the chemical to be most effective.
  • Store insecticide products in a locked cabinet not accessible to children.
  • Proper fertilization is important to prevent and allow the lawn to recover from grub damage.
  • Mow lawns immediately before applying an insecticide for grubs to remove weed flowers and protect bees.

Make a regular practice of mowing your yard with the mower on the highest setting (3.5-4 inches).

*What is 0.5 inches of irrigation? A half-inch of irrigation is when lawn sprinklers are run until a container like a coffee mug, or several mugs, fills to a level 0.5 inches up from the bottom of the cup.

Available products

Below is a short list of products now being sold for grub control as of April 12, 2016, in stores checked in the Mid-Michigan area. An online search indicates there are other products that will be available at other stores. Check the active ingredients.

Available preventive products

  • Scotts Grub-Ex - Granular
    chlorantraniliprole 0.08%
    Apply between April 1 and May 30 (no later than July 15) for best results.
  • Bayer Advanced Season-Long Grub Control and Turf Revitalizer - Granular
    imidacloprid 0.25% and a low fertilizer rate (6-0-1)
    Apply between June 1 and July 15 for best results.
  • (local distributors name) Premium Grub Control (Do not confuse with “Premium Insect Control”)
    imidacloprid 0.2% - Granular
    Apply between June 1 and July 15 for best results.
  • Bayer Advanced Complete Insect Killer Liquid attach-to-hose-bottle
    cyfluthrin 0.36% and imidacloprid 0.72%
    Apply between June 1 and July 15 for best results.
  • Bayer Advanced Complete Insect Killer Granules - Granular
    cyfluthrin 0.05% and imidacloprid 0.15%
    Apply between June 1 and July 15 for best results.

Available curative products

  • Sevin Lawn Insect Granules - Granular
    carbaryl 2.0%
    Apply in spring or fall to active grubs.
  • Bayer Advanced 24 hr Grub Killer Plus - Granular
    trichlorfon 9.3%
    Apply in spring or fall to active grubs.