Japanese Beetle Control and Management

The Japanese beetle is a serious pest to the Maryland area. The beetles can destroy your turf and ornamental plants quickly.  The beetles were first found in the U.S. in the early 1900’s being accidentally introduced in New Jersey. Up until that time the insects were only known in Japan. Our Maryland climate is perfect for this destructive insect with hundreds of species of plants for the adult beetle to feed on. With no natural enemies, the beetle thrives and their population increases every year.

Description of the Japanese Beetle

The adult beetles are about 7/16 of an inch long with a metallic green body with copper brown wing covers. They are easily noticed emerging from the ground and begin feeding on plants in June. The beetles are very active for 4 to 6 weeks. The average Japanese beetle will live approximately 30 to 45 days. They tend to be most active on warm sunny days and prefer plants that are in the direct sunlight. Eggs are laid soon after the adults emerge and mate. The females will burrow about 2 to 3 inches into the ground and lay their eggs. The eggs will hatch and the grubs will spend about 10 months in the soil as white grubs about 1-inch long. The grubs will feed on the roots of turf grasses, vegetables, and other plants. Their feeding will quickly damage the plants they are feeding on.

How to Control Japanese Beetles

It is important to realize that these pests cause damage in two different ways. In the grub form, they can be found when planting flowers or other plants in the soil as they feed on the root systems.  If you notice your lawn dying in patches you can check by pulling on the dead patch and if it pulls up easily this is a sign that the roots have been eaten by grubs.  Check the surrounding living grass to see if there are grubs in the soil just below the roots. The heaviest months of feeding are from June to September.  The second stage is the adult beetle form. This is when you will see the green and brown beetles eating thousands of holes in the leaves of many tree and shrubs.

Treating the turf or grass with a grub control treatment will prevent the grubs from feeding on the root systems. It is important that your landscaper apply a permitted insecticide at the appropriate time.  Different products can be used at different times depending on the infestation and grub or beetle stage of the insect.  Typically, June through September are your main treatment times. Usually, a granular product is preferred for the grub stage but it is important to water the product into the soil right away to ensure the product can get into the soil before the sun can break it down and render it useless.

Different methods of insecticides can be used to treat adult populations of the Japanese beetle. It is best to ask your professional landscaper to handle spraying any insecticide to ensure you are using an approved insecticide that will not cause damage to other animals or plants and is safe for rain runoff.

Some people ask about Japanese beetle traps. In most landscape situations, the use of the traps probably will do more harm than good as they will attract the beetles to the trap and the beetle will generally feed on nearby plants prior to entering the trap. If you decide to experiment with traps, be sure to place them well away from gardens and landscape plants. The Japanese traps are sold in many garden centers and use baits that mimic the scent of virgin female beetles and is highly attractive to male beetles.

If you are experiencing damage to your turf or ornamental trees or suspect that you have grubs, call American Landscaping Inc. at (301) 384-4486. We will be very happy to help you get your Japanese beetles and grubs under control!

American Landscaping Inc.

(301) 384-4486