Japanese Beetle Poses Serious Threat to Fair Oaks Flora

One year ago a male Japanese beetle was picked up in an area of Fair Oaks through an annual detection program sponsored by the California Department of Food and Agriculture (CDFA). Now it would appear the species has been rediscovered in that immediate area.

Two more Japanese beetles have been detected in Fair Oaks, in the vicinity of Greenback Lane and Fair Oaks Boulevard.

The discovery of the beetle one year ago triggered a delimitation program in Fair Oaks to trap any more of the species, said Juli Jensen, acting agricultural commissioner.

"That involves trying to narrow down the area where the beetle is," said Jensen. "When we have a find, the area is much more intensely tracked to try to narrow down exactly where the beetle is if there is an infestation."

Since the discovery of the beetle last year and now two more, it does indicate a breeding population in Fair Oaks. Last year's discovery of the beetle was a first for the area, Jensen said, though it's not her first encounter with the species in the area. Some 20 years ago Jensen was introduced to the beetles in an area of Orangevale.

According to the U.S. Department of Agriculture (USDA), the Japanese beetle is the most widespread turf-grass pest in the United States and expenditures to control this pest are estimated at more than $460 million a year.

The beetle is known to cause extensive damage to ornamental plants like roses or cut flowers. Adult beetles feed on the leaves, flowers, and fruit of more than 300 species of plants; while larvae, also known as grubs, live in the soil and feed on plant roots, especially those of grasses. An adult Japanese beetle is a little less than 1/2 inch long and has a shiny, metallic-green body and bronze-colored outer wings, with small tufts of white hair along the sides of its body, under the edges of its wings.

“The good news is that the infestation appears to be localized,” said Jensen. “Residents in this area should not move plants or plant parts to keep this infestation from spreading throughout the County.”

Treatment for the elimination of the beetles will involve the use of an insecticide, Jensen said. Since the beetle is an invasive species, it is not a contributor to the natural local ecosystem, Jensen explained.

When asked about the effects of the spray on other insects in the ecosystem, Jensen said, “The Japanese beetle is an insect, and insecticides are being used to eradicate it, so other insects could be affected. The CDFA has taken this into account and is using materials that will have the least toxic effect on the environment and yet still eradicate the Japanese beetle.”

The eradication project is being carried out by the Department of Food and Agriculture, Jensen emphasized, not by Sacramento County. One of the materials used in the eradication process will be carbaryl, an insecticide known to be detrimental to bee populations, "if they (the bees) visit the area when it is still wet," Jensen said.

"We have already been in contact with beekeepers and those bees will be removed just prior to our treatment in order to protect them," Jensen said.

Japanese beetles generally infest the Eastern Seaboard, spreading south to Alabama and west to Mississippi.

Representatives from the Sacramento County Department of Agriculture, the CDFA, the California Department of Pesticide Regulation (CDPR), and the Office of Environmental Health Hazard Assessment (OEHHA) will be on hand for an informational open house to be held today at the Orangevale Recreation and Park District Meeting Room, 6826 Hazel Avenue. The meeting, which is open to the public, will be from 5:30 to 7:30 p.m.

Residents and anyone with questions about the treatment program are invited to attend. On August 2, CDFA is scheduled to begin ground applications of carbaryl on fruit bearing trees, and cyfluthrin on non-fruit bearing trees and landscape plants. The initial treatments will be directed at adult beetles. Two weeks later, a second final treatment will be applied and augmented by a granular imidacloprid, a systemic treatment, to target grubs.

The applications, to occur on approximately 100 properties, will be carried out by CDFA staff and subcontractors following all pesticide use laws and regulations, with advance and post-treatment notices to residents. The Agricultural Commissioner’s pesticide use enforcement staff will randomly monitor some of the applications. CDPR, which approves pesticides for use in California, will provide environmental monitoring during the treatment. The public can help by not moving plant material, cooperating with agricultural officials and reporting suspicious bugs to the CDFA PEST HOTLINE at 1-800-491-1899. For more information, visit CDFA’s website at www.cdfa.ca.gov.