Japanese Beetle adults are starting to emerge now, soon to be followed by European Chafer beetles. Look for these shiny green and copper beetles feeding on grapes, roses and other flowers. Where possible, knock adult beetles into a bucket of soapy water to drown them.
The adults will mate and lay eggs that hatch into white, C-shaped, soft-bodied larvae with legs near the head, which feed on grass roots, causing sections of the lawn to die.
Skunks and raccoons find the grubs tasty treats, so they pull up your sod to get at them. If your lawn is infested, you will begin to see dead patches and pulled up sod around the end of July / beginning of August.
Mid- to late August is the time to apply beneficial nematodes to control the grub problem. Irrigate the soil prior to application. Never apply nematodes in direct sunlight and water well for 10-14 days after the application. Nematodes are available from garden centres.