How to Get Rid of Japanese Beetles
One of the best methods of Japanese Beetle removal is getting rid of grubs using Imidacloprid granules. The larval form of Japanese Beetles (grubs) cause lawn problems because they eat the roots of the grass. Treating the grubs before they emerge as an adult will help curb the population. The best time for spreading the granules is June to August which helps catch the newly hatched grubs. The Imidaclorprid granules last for two months.
If you use a trap like the Bonide Beetle Bagger, it is recommended that you use a repellent insecticide like Bifen IT on plants. Place the Beetle Trap away from the area that you want to protect.
For a organic approach, you can use Neem Oil
Japanese Beetles look for plant food and begin eating plants in June and July. If your plants are sprayed with repellent insecticides, the beetles are less likely to eat the plants and are encouraged to go the Japanese Beetle Traps. Without the repellent insecticide on the plants the trap may draw in more beetles than you actually trap. Simply put the traps may increase the population if used alone without the insecticide. After heavy rains it is advisable to retreat.
Photo: By Bruce Marlin via Wikimedia Commons