About Japanese Beetles

The Japanese beetle is native to Japan. Like many insects from all over the globe, it came to the United States through the shipping industry. It is said that this version of the beetle made its way to the States in a shipment of iris plants from Japan in the 1910s.

It was first discovered in the New Jersey, in 1916, meaning the Beatles were most likely here at least a couple of years before that.

Since then, the Japanese beetle has got in most of the remaining 50 states; serious infestations are in states near the Mississippi River, including Ohio, Georgia, Tennessee, and North Carolina.

There have also been infestations in:

  • Texas
  • Mississippi
  • Oklahoma
  • Kansas
  • South Dakota
  • Nebraska

The Japanese beetles are also found in, Portland, too, though the climate of many states out west aren’t suitable for the Beatles’ survival.

What do Japanese Beetles Feed On?

Japanese beetles are known to feed on around 300 kinds of plants, according to the University of Kentucky. Sometimes the beetles may use the plants as fuels as well.

1. Trees

Certain species of trees the beetles like are birch, maple, cherry, and crabapple. The beetles are known to stay away from oak and evergreen trees, another reason outside of the environment as to why beetles don’t usually stay in the Pacific Northwest.

2. Vegetation

Beetles like feeding on crops, which is part of the reason why they’re not in certain regions. The beetles feed on plants that produce fruits and vegetables such as raspberries, blueberries, peppers and tomatoes, and grapes.

They also feed on other vegetables and food including carrots, corn, beans, plantains, and asparagus. This is why Japanese beetles can be annoying to farmers.

3. Flowers

Japanese beetles are also attracted to plants like poison ivy, roses, morning glories, and lilacs because of their sweet smell. This affects our garden and lawn appearance in addition to affecting the surrounding environment.

Many of these plants are affected when the beetles live above the surface in their adult stage. While below the ground, mobility is limited, so the beetles feed on the roots of grass and surface near where the females lay the eggs.

What do they look like?

It’s easy to recognize the beetle by its unique appearance. It has a copper-colored back, metallic blue-green head and tiny white hairs that line the sides of its stomach. These insects have 6 legs, 2 antennae, and wings.

It looks unique, as it didn’t originate in America. Until early in the 20th century, these bugs were just found in Japan. Geographic isolation and particular predators, native to the island nation kept the beetle from spreading.

How do Japanese Beetles Survive?

Japanese beetles are annoying, somewhat-menacing pests. They emerge in their adult phase with a metallic green body and copper wings, which they use to fly from plant to plant.

The Beatles are known to create a mess on vegetations, plants, and lawns all over the eastern United States, and they do so just being about half an inch long in their adult phases. Once they are adults, they do their damage in a life period that lasts about a month to a month and a half.

Adult female beetles lays up to 60 eggs in a 45-day period, as explained by the entomology department at the University of Kentucky.

The eggs are laid during the afternoon time a couple of inches under the soil in June and July, and they hatch a couple of weeks later. This then begins a long period of living underground and nourishing on the roots of grass and turf.

The Beatles spend whole life underground, and their eggs are saved from drying out due to the consistent rainfall in the mid-summer months. That’s why many of the states in the eastern U.S. are excellent for Japanese beetles; they have moist, rainy summers.

Known as “white grubs,” the previously hatched larvae of Japanese beetles grow on the surface during the winters. They hibernate during the cold seasons, too, diving further underground for warm temperature.

Once the weather and soil get warmer, the larvae start to elevate back to the surface and enter the pupa phase, a four- to six-week time of feeding as an almost-hatched beetle before they emerge in the month of June as adults.

Frequently asked Questions

1. How to control Japanese beetles?

Begin by spraying the affected plants with Japanese Beetle Killer (pyrethrin) or neem at the initial sign of invasion. The pyrethrin-based insecticide is a safe and useful way to control these pests on grapes, vegetables, roses, raspberries, trees, flowers, and shrubs.

2. What attracts Japanese beetles?

The scents of some kinds of fruits, flowers, and plants, as well as the pheromones of different Japanese beetles, bait these pests on almost any yard with big, open patches of grass. Certain kinds of plants are more feasible to attract Japanese beetles.

3. What birds eat Japanese beetles?

One of the many birds that eat both the beetle larvae and adults is the starling. Finally, something practical can be said about this common bird. A few other birds that eat grubs and sometimes adults include:

  • Crows
  • Robins
  • Blue jays
  • Sparrows
  • Wild turkeys
  • Ducks
  • Cardinals

4. How long do Japanese beetles stay around?

Adults come from the ground and begin feeding on plants in the early summer. The peak of their activity lasts from the months of late June through August or September when they will proceed to die off due to temperature and climate. Japanese beetles live for up to 2 months during their adult life form.

5. When to spray for Japanese beetles?

In the grub phase of late spring and fall (beetles have 2 life cycles per season), spray the lawn with two tablespoons of liquid dishwashing lather diluted in 1 gallon of water per 1,000 square feet. The Japanese beetles will surface. Sprinkle once each week until no more Japanese beetles surface.

6. What plants repel Japanese beetles?

It may seem tremendous, but there are actually plants that Japanese Beetles avoid. These plants typically have a powerful scent and don’t taste good to the insect. Some of the plants that prevent Japanese Beetles are:

  • Onions
  • Catnip
  • Larkspur
  • Chives
  • Leeks
  • Marigolds
  • Garlic
  • White Chrysanthemum
  • White Geraniums
  • Tansy