If your dog or cat is scratching itself, it's most likely caused by fleas, says Virginia Tech University. Fleas often hide in your landscape and jump onto you or your pet as you walk by their hiding place. Your lawn can serve as the home of thousands of fleas. Defend both you and your pet's health and comfort by killing the fleas in your grass using a combination of chemical and nonchemical strategies.
Maintain your landscape by pruning back dense shrub growth, removing weeds and keeping grass mowed low. This exposes the area to more sunlight, which kills both flea larvae and their eggs, according to the University of Tennessee.
Soak your lawn with water so that the grass and soil surface is evenly wet. Fleas drown easily and this will help control the flea population. Allow the lawn to dry, then pull on white socks and walk across your grass. If you still have many fleas, they'll appear as black dots clinging to your socks and you'll need to treat your lawn with chemicals.
Sprinkle your lawn with water again. This forces the surviving fleas to climb onto the top of the grass, suggests Texas A&M University. Otherwise, the grass blades will shield the pests from the insecticide.
Spray your lawn with an outdoor insecticide formulated with diazinon, carbaryl or deltamethrin, according to Ohio State University. Apply the insecticides according to their labeled guidelines, since toxicity varies by product. These sprays will kill fleas upon contact. Retreat the lawn 45 days later to catch any fleas that you may have missed the first time around.