Grubs can damage your lawn very quickly. Your lawn can go from looking healthy to dead almost overnight because of the damage they cause. Grubs are beetle larvae and they are most active in the late summer and early fall. They feed on the roots of your grass, so you will never see them causing any problems until one day you find your grass brown and dead. There are many methods to get rid of grubs, but the most reliable is to use an insecticide that is targeted at grubs.
Sample a section of your lawn to verify that you really do have a grub problem. Take a bulb planter and push it into the soil to remove a core. Look between the roots and soil of the core and count how many grubs you have. If you see five or more, you have a grub problem.
Set up lawn sprinklers and irrigate the entire lawn with a half inch of water before applying the insecticide. Use a pan to measure when a half inch has been applied.
Pour your grub killer insecticide into your broadcast spreader. Set the dial to the setting indicated on the grub killer bag.
Walk back and forth across the entire lawn until all the insecticide is spread.
Turn on your sprinklers and apply another half inch of water over the entire lawn.