Japanese beetles, as their name suggests, initially came from Japan. Back there, they were considered as minor agricultural pests, mainly because of their natural enemies, which feed on them, and the unfavorable temperature in Japan for these beetles. They are more significant pests in the United States, infesting turfgrass and ornamental, horticultural, and agricultural plants. They were then introduced to the United States in 1916 in New Jersey by accident. They were said to have been carried here through the rhizomes of Japanese iris. They have adapted to the environment here and have thrived since then.
It is also a fact that they are more successful here than they ever were in their home country. Japanese beetles are abundant in the Midwestern area but are poised to spread damage to more parts of both the United States and Canada. They initially caused damage to plants like roses, beans, grapes, and raspberries. Unfortunately, they eat any type of plant and are not choosy at all, which - along with the temperature here in the U.S.- is the main reason why they are so successful here. Right now, Japanese beetles are firmly established in 28 states across the United States, with 6 other states partially infested.
Japanese Beetles are difficult and expensive pests to manage. The cost of doing this is estimated to be around $450 million in the United States, and that is for turfgrass management alone.
Identifying The Japanese Beetles
The size of the Japanese beetles is about ½ inch in length. They have metallic blue-green heads, with copper backs and tan wings. They have miniature white hairs on the sides of their abdomen. They feed in small groups.
Japanese beetles lay eggs in the soil, usually in the middle of the year. These eggs develop into small white grubs that have brown heads and 6 legs. These grubs are about ¾ inch long. They will remain in the ground for about 10 months, in which time they will overwinter and grow. They will emerge from the soil 10 months after as adult Japanese beetles and will start to feed by the middle of the following year, usually around June. Adults can live for only an additional 40 days, but can already do a lot of damage by that time. They also attract other Japanese beetles from around the neighborhood, making the damage so vast.
The Japanese beetle is described as a generalist herbivore. This means that they will feed on any plant that is available to them. They do show preference to other plants.
They undergo a complete metamorphosis their whole lives. They go through the egg, larvae, pupae, and adult stages. The eggs are about 1.5 mm in diameter. They are elliptical but can also be spherical. They are laid singly at a depth of 4 inches in the soil. They come in translucent to creamy white colors.
The larvae are shaped like a letter C. They are white grubs with a yellowish-brown head. They have mouthparts that are capable of chewing, with 3 pairs of thoracic legs, as well as 10 abdominal segments. Their bodies are covered with brown hairs. Most of these hairs are at the dorsal side and at the tip of the abdomen. A newly hatched larvae are ⅛ inch in length, while fully grown larvae are 1 and 3/16 inches.
The pupae have legs that are not attached close to their bodies. They now resemble an adult, though not quite. They come in cream to tan, to metallic blue-green in color. They are 1/2 inch long, and 1/4 inch wide.
The adults, just as described above, are ½ inch in length and ¼ inch wide, metallic blue-green heads, copper backs, and tan wings.
Japanese Beetle Damage
We should never ever underestimate the damage Japanese beetles can cause. They can completely destroy landscapes and crops. Because of the fact that they feed on a wide variety of plants and crops, they are so destructive. They are common in roses, beans, grapes, and raspberries. They wreak havoc on plants, vegetation, gardens, and lawns in many states here in the U.S.
The larvae are destructive to turfgrass roots. This includes lawns, athletic fields, tennis courts, and golf courses. The adults feed on the leaves of the plants. They eat between the veins and they leave a characteristic skeletonized appearance on the leaves.
Japanese beetles can feast on most of the foliage of a wide variety of plants and flowers. The skeletonized leaves are one sure sign of their presence, they do not go far from the leaves that they have just recently devoured, so you may look for them around the damaged plant; you may most probably spot them.
In the lawn, you may spot brown, unhealthy patches. They damage the grass while overwintering in the soil. They feed on the roots of the lawn grasses and garden plants. This causes unsightly brown patches of dead or even dying grass in the lawn. You may pull them easily because their roots are weakened.
They are present in several states, but the worst infestations are in Georgia, Ohio, Tennessee, and unfortunately, here in North Carolina.
What Do The Japanese Beetles Eat?
1) Trees - Japanese beetles feed on maple trees, cherry, birch, and crabapple.
2) Flowers - They eat roses, poison ivy, lilacs, and morning glories. They are attracted to it because of the sweet and attractive scents given off by these flowers.
3) Vegetation - Japanese beetles feed on crops too, making them economically destructive. The like to feed on produces such as tomatoes, grapes, raspberries, blueberries, peppers, grapes, plantains, beans, and asparagus. Climate models have also now shown that Japanese beetles are suitable to areas that are planted with soy and corn, though they have not infested these areas yet.
Climate Change: What Impact Does It Have On The Japanese Beetle’s Survival?
According to a study that was published in the Journal of Insect Science, “a 3.5 degree Celsius increase in temperature by the year 2050 in the midwestern United States could boost the feeding window for the Japanese beetles by almost 200 percent. At the same time, models have predicted that the same climate change could reduce beetle populations in places like Arkansas, because of the hotter and drier conditions there”.
These studies show what eventually would be their suitable habitat here in the United States.
Control Tips Using Integrated Pest Management
First of all, Integrated Pest Management is the use of all available pest control techniques that discourage the development of pest populations without really using chemical pesticides, or at least kept to acceptable levels to reduce risks to human health and the environment.
The initial step to controlling these beetles is to look for the adults in the garden or field and estimate the damage to the plants. Skeletonized leaves and brown patches are the signs to look for. If you spot a damaged leaf, chances are the Japanese beetles are just around the corner.
Once you discover where they are, you can use your hands to remove the beetles. After handpicking them, put them in a bucket of soapy water to kill them. If you see an infected or infested plant, remove it immediately so that the infection or infestation would not spread.
Encourage beneficial insects. Beneficial insects are those that feed on the pests that feed on your plants. These include parasitoid wasps, nematodes, and bacterial organisms. These are natural predators for larvae. For adults, on the other hand, it is much different to find a natural enemy because of its large size and rigid body. The winsome fly is used as a natural predator for the adults. Several groups of birds like chickens, ducks, pheasants, and meadowlarks are very good predators as well.
Sticky traps and other forms of traps are also effective in putting down the population of pests. These traps also help you monitor how bad the problem really is in your garden.
Unfortunately, there really is not one very effective way to get rid of pests, be it Japanese beetles, or other pests like mosquitoes, cockroaches, flies, etc. One thing that is constant is that you may hire a Raleigh exterminator to take care of your pest control needs.
Why Go-Forth Home Services?
At Go-Forth Home Services, we have expert professionals who will examine your home and your lawn to evaluate your individual necessity. We will identify points of entry and make treatments as necessary. We only use state of the art equipment to keep up with these ever-evolving pests. Our expert experience in exterminating pests like cockroaches, wasps, weevils, mosquitoes, mice, flies, termites, ants, and spiders can really make you say goodbye to these pests in your home.
Go-Forth Home Services has earned the trust of residents and businesses in North Carolina for more than 50 years. For more information, or to set an appointment, just dial (877) 274-1475. Our friendly operators are standing by.