Grubs are basically the larvae of June beetles, Japanese beetles and chafers. These C-shaped, off-white pests feed on grass roots, causing them to lose essential nutrients, wither and die, thus making way for a brown spot over the area. Immediate action is required to remove these pests from your lawn before they destroy it completely. There are chemical and natural methods of getting rid of grubs from your lawn depending on personal choice. The ideal time for treatment-application is from July to September, when the grubs are smaller and feeding near soil surface.
Determine the amount of area you want to treat. Measure the area around a brown spot caused by grubs, and include 2 inches around the edges to allow for a square or rectangle.
Read label directions for adding trichlorfon insecticide into a push broadcaster, or spread it by hand. Generally, use 1-1/2 to 2 lbs. for every 500 square feet of turf area. Apply an even amount over the infected area.
Saturate the spot with water so the insecticide granules melt and penetrate the soil to where the grubs live. Water your lawn frequently to make the soil evenly moist and thus reduce grub damage.
Spray the spot with a pesticide such as Milky Spore that does not harm worms, bees or spiders, but kills grubs. Follow manufacturers directions when applying this natural grub treatment evenly over the affected area. The grubs eat the powder and die, and release hundreds of spores in the soil to combat the next generation of grubs.
Use nematodes for a natural alternative for getting rid of lawn grubs. These microscopic worms feed on and reproduce within a grub's body and eventually kill it. Mix the contents of your package in a watering can and sprinkle over the area. Water well so they penetrate the soil.