1952年1月 · U.S. Department of Agriculture, Agricultural Research Administration, Bureau of Entomology and Plant Quarantine
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Japanese beetle quarantine procedures provide for the shipment of plants grown in nursery sections treated under supervision with 25 pounds of DDT or 10 pounds of chlordane per acre and cultivated into the soil to a depth of 3 inches. Annual retreatement to maintain these concentrations is required. For this purpose the soils are sampled and the concentrations are determined by chemical analysis. The tool approved for use in taking these samples is described in this paper