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Show 1 1 i i - ' ...... Horticullural Hiiats CONTROL OF CODLING MOTH Entomologists Find That Arsenate of Lead Is More Effective Than Nicotine Sulphate. trr'Pirfd by the United States Department Depart-ment of Agriculture.) Nicotine sulphate Is not ns edlclent In the control of' Tie codling moth n powdered arsenate of lend, It ban been shown In experiments conducted by entomologists of tho United States Department of Agriculture. For several sev-eral years nicotine nnd Its compounds havp been used agnlnst tiettnln soft-bodied soft-bodied Insects ns contact Insecticides, nnd within the past few years the question has been raised concerning the effects of nicotine sulphate upon the eggs and early Instnrs of other Insects In-sects which are commonly controlled by other menns. To obtnln reliable Information on this subject the depart incut entomologists conducted n series of experiments both Irs the laboratory and Held, a report of which has Just been published In Department Bub Hln n:i8. In the Inbnratoiy tests It was found ifmt nicotine sulphnte, with one excep. tlon, wns. Inolllclent ngnlnst the eggsof the silkworm moth, codling moth, tus lock moth nnd potato beetle. The eggs sprayed wjlh It were variously affected depending upon the strength of spray solution used, on tho nge of the cgzs tested, nnd whether or not the solution contnlned sonp. Upon the eggs of three of the species of bisects bi-sects used there wils practically no difference In the effects between solutions solu-tions contnlnlng sonp nnd those without with-out soap, although those with soap were much more cJTectlvo upon the eggs of tho tussock moth. Comparing the effects of (ho spray solution, 1:800. the strongest of the economic solutions used, tho percentages percent-ages of eggs sprayed with It that failed to hatch are as follows: Ninety-nine Ninety-nine per cent of the freshly laid eggs of tho silkworm moth, but only 75 per cent of the older eggs of the snmo Insect In-sect ; about 20 per cent of the codling moth eggs on npple tree foliage; 75 per cent of the tussock moth eggs (oe to three dnys old) ; and about 12 per cent of those of the same Insect which had been collected In the field; nnd practically none of tho potato beetle eggs. The field work was conducted by the depnrjmont entomologists during the season of 1017 In three Important apple ap-ple regions of the United Htntes the Jake roL-lon of Tlenton Harbor, Mich., r . ,,v ' '1 L 3 I Injury Wrought by First Brood of Codling Moth. the mountainous region of Grand Junction, Junc-tion, Colo, nnd tho semlnrld region nt Itowell, K M. The experiments show that nicotine sulphate l:S0O with sonp gave a fair degree of control for the codling moth nt Benton Harbor nnd Uoswell; but that U wns not ns effective as one pound of powdered arsenate of lead to SO gallons of water. wa-ter. It wns found also that there wns no practical ndvnntnge In combining arsenate of lead nnd nicotine sulphnte In sprays designed to control tho codling moth. At Grand Junction, where the Infestation was much heavier, heav-ier, nicotine sulphnte 1:800 without sonp was Inolllclent against the codling cod-ling moth. |