Page:Some recent developments in white pine weevil research in the northeast (IA CAT31009844).pdf/7

 1.Lindane emulsion Vi percent plus Aroclor 5460. 2.Heptachlor emulsion 2 percent. 3.Heptachlor emulsion 1 percent plus Aroclor 5460. 4.Endrin emulsion 1 percent plus Aroclor 5460. 5.Malathion emulsion 2 percent plus Aroclor 5460. 6.DDT emulsion 2 percent.

With at least one of these materials, weevil control is now possible with fall applications. On October 24 and 25, 1956, and three blocks of trees were sprayed with ½-percent Lindane emulsion, with the addition of like percentages of Aroclor 5460, replicated three times. In 1957 only 1 tree out of the 10,000 trees sprayed was weeviled.

PRAYING large plantations with helicopter has given very good control. The most satisfactory results were obtained when a solution or emulsion containing 2 pounds of DDT in 2 gallons of liquid per acre was applied in the spring.

Spraying with fixed-wing aircraft has not been so satisfactory. However, with some of the newer materials, both types of aircraft may give good control with a smaller amount of insecticide and liquid per acre.

Preliminary tests of a 2-percent granular formulation of Endrin gave promising results for the control of hibernating weevils at a rate of 1 pound Endrin per acre (5). Last winter several additional materials at rates ranging from 1 pound active ingredient per acre to ¼ pound per acre confirmed the promising results obtained earlier. Two materials, Aldrin and Heptachlor, resulted in no emergence of 5