Japanese Beetle - Treatment Concerns
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Japanese Beetle - Treatment Concerns

TREATMENT CONCERNS

JB treatments are given in the Japanese Beetle Harmonization Plan (JBHP) here.

There has been a concern about the reduction bifenthrin and chlorpyrifos from the market.

Dip Treatments ‑ B&B and Container Plants
Only plants grown in non-clay soil are eligible. This includes non-clay balled and burlapped, potted and containerized nursery stock with rootballs twelve (12) inches in diameter or smaller. The potted or balled and burlapped stock will be dipped so as to submerge the entire root ball and all growing media of the container or the root retaining materials into the solution. The submersion time should be a minimum of two (2.0) minutes and until complete saturation occurs, as indicated by the cessation of bubbling. Treatment must be applied between September 15 and April 15. Growing media must be at least 50o F at the time of treatment. Plants should not be shipped before they are well drained and can be easily handled. During the adult flight period all treated plants must be protected from re-infestation.

Chlorpyrifos (4E formulations labeled for dipping, including Dursban 4E). Apply at a rate of one-quarter (0.25) pounds active ingredient (8 ounces) per 100 gallons of water.

Bifenthrin (OnyxPro Insecticide).Apply at a rate of 14.4 fl. oz per 100 gallons of water.

Drench Treatments - Container Plants Only

Potting media used must be sterile and soilless, containers must be clean. Containerized nursery stock with rootballs twelve (12) inches in diameter or smaller and consisting of non-clay soil are eligible. Field potted plants are not eligible for certification using this protocol. Treat before Japanese beetle adult flight season (before June 1). Apply tank mix as a drench to wet the entire surface of the potting media. Avoid excessive irrigation following treatment to also reduce leaching of active ingredient. During the adult flight season, plants must be retreated after sixteen (16) weeks if not shipped to assure adequate protection. If the containers are exposed to a second flight season they 

must be retreated.

Imidacloprid (Marathon 60WP). Apply one-half (0.5) gram of active ingredient per gallon (or one 20 gram packet per 24 gallons water).

Bifenthrin (Talstar Select Insecticide, OnyxPro Insecticide). Mix at the rate of forty (40) fl. oz (Talstar  Select) or 14.4 fl. oz (OnyxPro) per 100 gallons of water. Apply, as a drench, approximately four (4) fl. oz of tank mix per six (6) inches of container diameter.

Thiamethoxam (Meridian 25WG). Apply as a partial drench (1/3 of full drench water volume) at a rate of 1.95 oz in 17 gal of water.

Media (Granule) Incorporation - Container Plants Only

Containerized nursery stock with rootballs twelve (12) inches in diameter or smaller and consisting of non-clay soil are eligible. All pesticides used for media incorporation must be mixed thoroughly into the media before potting and plants should be watered at least 2 times following media incorporation before shipment can begin. Potting media used must be sterile and soilless, containers must be clean and plants for potting will be free of Japanese beetle. Field potted plants are not eligible for treatment. If the containers are to be exposed to a second flight season they must be repotted with a granule incorporated mix or retreated using one of the approved dip or drench treatments. Pesticides approved for media incorporation are:

Imidacloprid (Marathon 1% G). Mix at the rate of five (5) pounds per cubic yard.

Bifenthrin (Talstar Nursery Granular). Mix at the rate of 25 parts per million (ppm) or 2.5 pounds per cubic yard based on a potting medium dry bulk density of 200 lb per cubic yard. (See definition of bulk density for specifics on how to calculate for media with other bulk densities).

Tefluthrin (Fireban 1.5 G). Mix at the rate of 25 ppm based on the dry bulk density of the potting medium. (See definition of bulk density for specifics on how to calculate for media of various bulk densities).

Bulk Density - The dry weight of a cubic yard of potting media. A formula for determining pounds of granular formulation per cubic yard of media for a 25 ppm dose rate is as follows:

Multiply media bulk density (in pounds) x 0.000025. Divide the result by the active ingredient concentration of the selected pesticide (for Talstar Nursery Granular, divide by 0.002; for Fireban 1.5 G, divide by 0.015). The result equals pounds of granular formulation needed to treat one cubic yard of growing media.

Example: Assume that potting media weighing 500 pounds per cubic yard is treated with Talstar Nursery Granular (500 x 0.000025) = 0.0125 divided by 0.002 = 6.25 pounds Talstar per cubic yard. Talstar and Fireban labels also provide tables and formulas for determining amount of pesticide to be blended into the potting media.

Methyl Bromide Fumigation

Nursery stock: methyl bromide fumigation at NAP, chamber or tarpaulin. See the California Commodity Treatment Manual for authorized schedules. Many plant cultivars may be severely injured by methyl bromide fumigation. To minimize injury, plants should be free of surface moisture.  However, pans of water should be placed around the chamber floor to lower the risk of plant damage. The fumigant should be injected into the chamber as a high temperature (210 oF) vapor and not as a liquid. Foliage should not touch the inner sides of the chamber or enclosure, and should be kept out of the direct air blast from the circulating and exhaust fans. For best results, the nursery stock should be at the temperature of the selected schedule before treatment. Material treated from October through April must be shipped before beetle flight or be protected from re-infestation. During the adult flight period all treated plants must be protected from reinfestation if they are held before shipment.