There are a wide variety of insects that live in the lawn. Some of them are beneficial, while some may cause issues with grass growth and maintenance. While under normal conditions, bugs in the lawn will cause little disaster, but when the population of bugs that feed off grass gets too large, control may be necessary.
Identifying whether lawn damage is caused by an insect is the first step toward control. Wilting, water damaged or damaged leaf blades may indicate the presence of an insect. Blade defoliation appears on the leaf as brown scars, while blade sucking appears as black lesions where the blade has been sucked on by a sap drinking insect, according to the University of Minnesota. Similar damage is caused by some diseases, so locating the insect responsible is important.
Finding the Insect
Examining the area that shows damage to find the insect responsible is required to determine the correct treatment. Insects that cause damage are not found in completely dead areas because their source of food is depleted. A coffee can with both ends removed and sunk into the ground, filled with water mixed with dish soap, will catch insects that are damaging the lawn for identification purposes. These insects may be sent off to a local university extension for examination.
Below Ground Insects
Some insects do not do their damage on the surface of the lawn, living instead under the soil. According to the University of Delaware, white grubs and some varieties of wasps will live under the surface. Wasps and bees that live under the dirt do not require control as the damage they cause to lawns is superficial. White grubs do require control.
Once insects are identified, a control program using cultural methods and pesticides will control an insect population. Cultural methods include keeping the lawn healthy to prevent the growth of insect populations. Proper fertilization of the lawn according to the grass variety will keep the grass strong and prevent insect damage from affecting its overall health. Mowing one-third of the blade at a time will reduce stress to the grass. Core aeration, the removal of 3-inch tubes of dirt from the soil, reduces compaction, increases water drainage and improves the health of the lawn.
Pesticides are used when all cultural control methods for insects have failed. The label of the pesticide will provide safety instructions as well as application methods. Generally, pesticides are spread as granules over a lawn using a fertilizer spreader. Wettable powders and most granules require a small application of water to activate their chemicals. Over-watering will cause runoff of the pesticide, so a small application at the recommended rate on the packaging is required. Long clothes, work gloves and safety glasses are worn to prevent pesticides from coming in contact with the skin.