Beneficial nematodes have been shown to be as much as 96% effective against Japanese beetle grubs in field studies. Although many species of beneficial nematodes are available, Heterorhabditis bacteriophora (Hb) nematodes are most effective against Japanese beetles, European chafers and other grubs that are lawn pests.
How long does it take for nematodes to kill grubs?
Most biologicals require days or weeks to kill, yet nematodes, working with their symbiotic bacteria, can kill insects within 24-48 hours.
What is the best treatment for grubs?
To kill grubs in the spring or fall, use carbaryl or trichlorfon. Always wear rubber gloves and rubber boots when applying insecticides to turfgrass. Make sure to irrigate the lawn with at least 0.5 inches of water* and allow the grass to dry before allowing anyone or pets into the treated area.