Overview
White Grubs vs Other Lawn Issues
It can be difficult to diagnose white grub damage since it can often appear as other lawn issues. However, there are some definite hallmarks of white grub activity. Being able to recognize symptoms of white grub damage and thoroughly inspecting your lawn will be vital to your white grub control efforts.
Step
1
Look For Lawn Grub Damage
Signs of Grubs in Lawn
White grubs feed on the roots of your grass, which leads to several symptoms of damage:
- Grass with damaged roots will begin to thin, yellow, and die.
- Irregular patches of brown grass will appear in random places in your lawn.
- Grass will feel very spongy and will pull up very easily. Since the roots are damaged, the turf will often roll up like carpet.
- Grass will be very vulnerable to drought and other stressors.
- Another sign of the presence of white grubs in your soil is an increase in activity of raccoons, moles, and birds digging in your turf, and even certain wasps flying low to the ground in your lawn. However, these animals also eat other insects and earthworms in the soil, so you should still inspect your turf/soil for the grubs before treatment to make sure you have white grubs.
Step
2
Inspect Soil For White Grubs
If you suspect you may have white grubs in your soil, you should inspect your soil to see if you have enough grubs in your soil to warrant control measures. A few grubs in the soil are normal and your grass should be healthy enough to withstand a few grubs feeding on the roots, but more than that can definitely warrant corrective action. Here are the steps to inspecting your soil for grubs:
- Survey the suspicious areas in your turf. August and September are good times to inspect the turf because the grubs will be active and close to the top of the soil.
- Start by using a spade to cut square foot sections of turf, about 2-4 inches deep in several different areas.
- Pull back the square foot area to expose the soil below.
- Closely inspect the turf, thatch, and soil for grubs.
- Generally, less than 5 grubs per sample is a normal amount that doesn't warrant control measures. More than 5 grubs per soil sample are enough to require control measures.
- Replace squares of sod and pat down. Water in patches to avoid drying.