How to Control White Lawn Grubs
- 1). Apply Heterorhabditis bacteriophora nematodes to your grass in late summer or early fall. These tiny worms enter the grubs and kill them with bacteria. Water your grass in the early evening. Mix the nematodes with distilled water and put the solution in a sprayer. Apply to the areas that have an infestation. Water your lawn again. Repeat the process in two weeks.
- 2). Apply synthetic insecticide to kill adult lawn grubs. Use this option as your last resort since it poses risks to the well being of other plants and animals. Rake the lawn to remove dead grass and other debris and water it thoroughly. Broadcast the granules and water the grass again to push the insecticide into the ground. Apply 3 lbs. per 1,000 square feet of grass.
- 3). Apply insecticide granules to kill the young larvae before they cause damage. Rake the grass to remove debris and water it. Broadcast 30 lbs. of insecticide granules per 1/2 acre of lawn. Following the application, water your lawn again to push the insecticide down to root level.
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