Out of Sight…Out of Mind
That expression may be the root cause of problems for many landscapes. It is always best to know what is going on in the soil underneath your grass and plan accordingly. Be proactive. Think back to the condition of your lawn over the last several years. Make notes of successes or problems. Did your grass improve year to year? Did you have a lawn full of weeds? At what time of year? Did insects or lawn diseases cause damage? How was your last soil test? Were deficiencies corrected? Plan ahead to take care of issues before they get out of hand. Let us know if we can be of help.
Lawn grubs are white, C-shaped larvae of certain beetle species such as Japanese Beetles, and June Beetles. Almost every yard has a few grubs. Properly maintained lawns can tolerate more grubs than a stressed, underfed lawn. Grubs live underground and feed on the roots of the grass and other organic matter in the top inch or so of soil, killing the grass. A large grub infestation can destroy any lawn.
Life Cycle of a Grub
Beetles emerge from the soil in early to mid-summer. They feed on plants and lay their eggs in the soil of your yard. Later in the summer the eggs hatch and the grubs begin to eat as much as they can. They are at their most vulnerable at this time. This is the best time to control grubs. As the weather gets colder in mid-fall the grubs move down deeper into the soil below the frost line to stay warm and hibernate. They are too deep in the ground to treat at this point. Damage to the lawn is not easily recognized at this time of year. When the soil warms up in the spring the grubs move back up near the surface. They feed again, more aggressively and enter the pupal stage. They are difficult to control at this stage. Lawn damage may become more apparent. The insect emerges from its pupae as an adult beetle during the summer. It searches for food and a mate. The cycle begins again.
How to Check Your Lawn for Grubs
Grubs can go undetected for a while and damage may be done to your lawn before you realize the problem. You may notice brown patches in your lawn in late summer. Unfortunately, many other things can cause brown patches, such as a fungus or drought. There are several signs to help you distinguish between the issues. Try to pull your grass out of the ground. If it comes up easily you may have a grub problem since the roots may have been eaten away. Also, racoons, skunks and birds may try to dig up your lawn to eat the grubs. The only way to confirm you have grubs is to check the soil. To do that you need to:
- Make three 12” long cuts about 3” deep. It should look like 3 sides of a square.
- Peel back the turf in that area and look for grubs.
- Check several areas and estimate the number of grubs per square foot.
- Replace the turf and water after checking for grubs.
If you find 5 or fewer grubs per square foot that may not be a problem for a healthy lawn. If you find 6 or more per square foot, you may want to treat your lawn. Ten or more per square foot should be treated.
How to Control Grubs
A healthy, thick lawn with a deep root system can tolerate some light grub damage if it occurs. The most common and effective way to control grubs is with chemical insecticides. There are several types. Timing is important depending on the type you use. A very common type of treatment will kill young grubs before they can do much damage. This treatment needs to be applied in the June/July time frame. Be sure to follow all safety measures when using a chemical treatment. Read and follow all label directions. There are also a few organic alternatives. One is Milky Spore, a bacteria that kills Japanese Beetle grubs. Another is beneficial Nematodes.
- Tip: Mow before your grub treatment to help the chemical reach the soil faster.
- Tip: In most cases the product must be watered in to be effective. Check the label.
Grass Roots Advanced Turf Program includes a Grub Control treatment in the package. This application will be done in June-mid July. If you are not on our Advanced Turf Program and would like information about the program, please contact us. If you have questions about grub control or are interested in a treatment, please let us know. Grass Roots holds both a Virginia Pesticide Business License and a Commercial Pesticide Applicator Certification.
We are now on Facebook. Please follow us for additional tips and information for your lawn and garden.
Wishing you and your family a wonderful summer. Have fun in your yard!