<5TA | r BOAKl UNITED STATES DEPARTMENT OF AGRICULTURE Bureau of Entomology and Plant Quarantine Washington, D. C. B. E. P. Q. 503 Revised March 15, 1940 Sec. 301.72-5c Administrative Instructions — Modifying the restrictions of the white- fringed beetle quarantine by authorizing treatment by methyl bromide solution of balled nursery stock of specified thickness Introductory note. — The instructions in circular B.E.P.Q. 503 issued on November 21, 1939, provided for treatment of nursery stock by a solution of methyl bromide for larvae of the white-fringed beetle and limited the treatment to balled and burlapped nursery stock with soil balls not larger than 6 inches in diameter, and provided for an exposure of 21+ hours at temperatures of 70° or above. As a result of more recent investigations, the instructions are now revised to provide that soil balls 7 inches in diameter may be so exposed for 8 hours at a minimum temperature of 65°. The modification is restricted, however, to treatment for larvae of the more common species of the beetle, Pantomorus leucoloma Boh., and does not apply to such treatment for the new species, P. peregrinus Buch., known to exist at present at Gulf port and certain other points in Mississippi. The former specifi- cations remain in effect for treatment of larvae of that species and are brought forward in the instructions which follow. TREATMENT AUTHORIZED Under the provisions of Regulation 5(a) (Sec. 301.72-5) supple- mental to Notice* of Quarantine No. 72 (Sec. 301.72), the Chief of the Bureau of Entomology and Plant Quarantine hereby authorizes as a pre- requisite +0 certification, the following method of treatment for balled plants, when carried out under the supervision of an authorized inspector of the United States Department of Agriculture. TYPE OF MATERIAL AUTHORIZED For the more common species, P. leucoloma. — The treatment shall be applied only to plants in soil balls not greater than seven (7) inches in diameter nor greater than seven (7) inches in thickness when not spherical. For the new species, P. peregrinus. — The treatment shall be applied only to plants in soil balls not greater than six (6) inches in diameter nor greater than six (6) inches in thickness when not spherical. UNIVERSITY OF FLORIDA illinium 3 1262 09312 1621 - 2 - TREATMENT METHOD F"»r both sppcies of white-fringed beetle (a) Thp soil balls around the roots of plants must be buried in sand and plunged in boxes or trays approximately one foot deep, which ■.atertight. (b) A 2-inch space filled with sand shall be provided between the soil balls, also above and beneath them. (c) Such soil balls shall be treated with a solution of methyl bromide and alcohol at a concentration of 0.3 percent methyl bromide and 0.6 percent denatured ethyl alcohol by volume in water. The solution is to be prepared by first mixing the methyl bromide and alcohol together and then adding this mixture to the water and mixing thoroughly. (d) The aqueous solution of methyl bromide and alcohol shall then be applied evenly over the surface of the sand around the plants at the rate of £0 gallons per 100 square feet of surface area by means of a sprinkling can or sprayer. Exposure and temperature for the more common species (P. leucoloma) (e) After the required dosage has been applied, the soil balls shall remain embedded in \he sand for a period of* 8 hours. (f) The temperature of the soil bails during the treatment shall not be lower than 65° F. Exposure and temperature for the new species (P. peregrinus) (g) After the required dosage has been applied, the soil balls shall remain embedded in the sand for a period of 2U hours. (h) The temperature of the soil balls during the treatment shall not be lower than 70° F. DISCLAIMER There has been no opportunity to test this treatment on many vari- eties of plants, and it is understood that no liability shall attach either to the United States Department of Agriculture or its employees in the event of injury to either plants or operators. CAUTION Methyl bromide is a gas at ordinary temperatures. It is colorless and practically odorless, and in preparing the solution the operator should wear an approved gas mask/ (Sec. 301.72-5) [3. E. P. Q. 505, ;;d March 15, 1940] This revision supersedes circular B. E. P. Q. 503 dated November 21, 1939. AVERY S. H0YT, Acting Chief, Bureau of Entomology and Plant Quarantine.