The oriental or Asiatic beetle is an introduced species (first detected in Connecticut in 1920 from Japan) in the scarab beetle family (Scarabaeidae) that is typically smaller than the Japanese beetle (Popillia japonica) as an adult. Adults are typically 4/10 - 1/2 of an inch long, with the stout (broad), oval body typical of scarabs. Adult coloration can be variable, ranging from a black color to mottled gray with black patches/patterned markings. Adults are seen typically in mid-June and can be found through at least early August in MA. Adult beetles are active in the evenings/night time. Eggs are tiny and round in shape and females lay them 2-4 inches below the surface of the soil. Soils that are more saturated with water may be preferred for egg laying, but dry locations can be used by adult females as well. Extremely dry soil, however, prevents egg development. Eggs hatch, and grubs are nearly identical in appearance to the grub (larval) stage of Japanese beetle (c-shaped white grubs that grow at least to 3/4 inch long). Grubs can be distinguished between different species by looking at the raster pattern. oriental/Asiatic beetles have parallel rows of setae (hairs) on the raster which may be viewed with magnification, such as a hand lens. To differentiate between scarab beetle grubs in turf, visit: White Grub Identification. By late July, the larvae (grubs) can cause serious damage to turfgrass and ornamental plants. The roots may be eaten and the crown girdled. This may lead to wilting and yellowing of foliage. Grubs also feed on dead organic matter in the top 2 inches of soil. At least two instars of the larvae are known. In the fall, grubs burrow deeper into the soil to overwinter. Once soils warm in the spring, grubs move back to the soil surface and continue to feed for a month to just over a month. Once feeding is complete and grubs reach maturity, they burrow back deeper in the soil and pupate in an earthen cell. Following pupation, adults emerge again in the early summer. There is one generation per year.
Anomala orientalis beetles can feed on flowers such as daisy, roses, phlox, and petunia as adults; although typically, the feeding by the adults is not severe. Larvae often coexist with those of the Japanese beetle and can be very difficult to distinguish from them. Larvae can damage the roots of turf grasses as well as the roots of many nursery plants and small fruits, including containerized plants. Common ornamental hosts include hemlock, holly, rhododendron, azalea, juniper, and andromeda. Feeding by the larvae of this species on roots may lead to host plant yellowing or wilting of foliage.
At home, a light trap may be fashioned out of an outdoor-safe light bulb suspended above a flat pan of soapy water. This technique can be used to monitor for the presence of this insect if it is a suspected cause of damage on high-value host plants, however it is unknown whether or not this will effectively reduce damaging populations of the adults. Light trapping for the adult beetles may be more effective for monitoring purposes, than management or reducing damage caused by the insect.
Hand-pick adults when appropriate and remove and destroy, however this must be done at night. Light traps may be used to trap adult beetles that are active at night, however the efficacy of this is not completely understood. Suspending a light bulb over a pan of soapy water may attract the adult beetles who will then become stuck and perish in the pan. It may also be important to place traps away from favored host plants to avoid accidentally attracting this insect to suitable hosts.
A parasitoid wasp is known to lay its eggs in oriental/Asiatic beetle larvae (grubs). Tiphia vernalis is a tiny, dark colored wasp whose larvae feed on oriental beetle grubs. Additionally, Tiphia popilliavora is another parasitoid mentioned to be associated with oriental beetles. The larvae of this species are also susceptible to a bacterial disease (Paenibacillus popilliae), entomopathogenic fungi (Beauveria bassiana and Metarhizium anisopliae) and entomopathogenic nematodes (Steinernematidae and Heterorhabditidae) (CABI Invasive Species Compendium).
Acetamiprid (L)
Azadirachtin (larvae) (NL)
Bacillus thuringiensis subsp galleriae (NL)
Beauveria bassiana (NL)
Bifenthrin (NL)
Chlorantraniliprole (NL)
Clothianidin (NL)
Cyantraniliprole (NL)
Dinotefuran (NL)
Flonicamid+cyclaniliprole (N)
Tau-fluvalinate (NL)
Imidacloprid (larvae) (L)
Isaria (paecilomyces) fumosoroseus (NL)
Lambda-cyhalothrin (L)
Neem oil (NL)
Permethrin (L)
Active ingredients that may be applied systemically include: acetamiprid (injection), azadirachtin (injection, soil drench), chlorantraniliprole (soil drench), clothianidin (soil drench), cyantraniliprole (soil drench, soil injection), dinotefuran (soil drench), imidacloprid (soil drench), and neem oil (soil drench).
Larvae may feed on the roots of containerized plants or nursery stock.
Make insecticide applications after bloom to protect pollinators. Applications at times of the day and temperatures when pollinators are less likely to be active can also reduce the risk of impacting their populations.
Note: Beginning July 1, 2022, neonicotinoid insecticides are classified as state restricted use for use on tree and shrub insect pests in Massachusetts. For more information, visit the MA Department of Agricultural Resources Pesticide Program.
