Going to the hardware store on the weekend is something many homeowners do, especially in the spring. People stock up on fertilizers, weed control products as well as controlling insect pests in and around the home, and in landscape, gardens and lawns.
In regards to insects, it is estimated that there are over 1 million identified species of insects and probably several times that number is yet to be discovered. Fortunately, there are only about 2 dozen species of insects that feed on lawns. It is hard to say which of these insects are the most damaging, but the species that seems to be the most discussed are white grubs.
What Are Grubs?
Grubs are the larval stage of a scarab beetle. There are several different species of beetles that produce grubs that damage lawns. In the Midwest, Japanese Beetles and Northern Masked Chafers are the most common. The Japanese beetle causes the most damage as the adults feed on many trees and flowering plants and the female adult lays her eggs in turf areas, which then hatch into lawn-damaging grubs.
In the South, Japanese Beetles, Green June Beetles and Southern Masked Chafers are the most common species. In the Northeast, Asiatic Garden Beetles, European Chafers, Oriental Beetles, Northern Masked Chafers and Japanese Beetles are the most common.
Most grub species feed on the roots of turfgrasses in the late summer into early fall. They act like little sod cutters feeding on the roots of the turf grasses. If a lawn is being watered and fertilized on a regular basis, the damage may not even be noticed unless the population of grubs is above 20 per square foot.
The bigger problem is damage that is caused by skunks, raccoons, armadillos and other foraging animals, who rip up a lawn in search of a late-night snack. It is not clear as to why these animals know that grubs are present in a lawn, but most speculation points to either their ability to hear their feeding or smell grubs. Unfortunately, there is no product that will prevent the skunks, racoons, and armadillos from tearing up a lawn.
Treatment for Grubs
Good grub control requires the material be applied at the appropriate time. Most grub control products are insect growth regulators that prevent grubs from getting larger. Therefore, it is critical that the material is applied before the eggs hatch.
Look for products that contain certain active ingredients to control grubs. Chlorantraniliprole, Imidacloprid, or Trichlorfon will help control grubs and surface insects, prevent grubs from growing after they hatch or will control existing grubs if its actively feeding in a lawn. Products with these ingredients need to be watered in to move the solution into the soil where the grubs are active. Note that grubs will still be present for several weeks before they are completely gone.
Applying an insect or pest control in the spring is usually not recommended as the grubs are not feeding enough to ingest enough of the material to kill them. The best thing to do is to make sure you apply a grub preventative in early summer to avoid a problem with grubs later on. The solution will prevent the eggs from hatching or growing in your lawn.
Contact your local neighborhood Spring-Green lawn care professional to assist with grub damage on your lawn areas. They will provide you with the program and products to help keep your lawn free from grubs.