150 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 5 



on nine separate tests and these tests were again duplicated in 

 four poison series, making thirty-six separate tests in all for each 

 spray used. Three early sprays were used separately and in combina- 

 tions of two, making six different spray sets besides the unsprayed 

 one or seven sets in each orchard on each variety. 



The lead arsenate (5 lbs.) was used as the standard of efficiency 

 and the results with this poison were so high that it was thought worth 

 while to present them to the society as indicating the efficiency of this 

 method of spraying, even under the adverse conditions explained 

 below. 



The Orchards Used. The Stillman orchard (S) was the first to 

 blossom and the first sprayed. It did not have enough trees of any 

 one variety to carry on all of the tests, so that half strengths and the 

 third spray were omitted. In addition to the varieties used in the 

 other orchards, Rome Beauty was added to these tests. A frost took 

 the larger part of the crop, leaving the distribution very irregular, 

 some trees having nothing left, and some Winesaps running as high 

 as 2,500 apples. The check trees averaged 475 apples. 



The Woodbury orchard (W) was sprayed next, as in the other two 

 orchards, the tests w^ere carried on, on Gano, Jonathan and Winesap 

 trees. Frost reduced the crop here even below that at the Stillman 

 orchard. The check trees averaged 325 apples. 



The Nokes orchard (N) was last sprayed and it was a little late by 

 the time this orchard was reached, some of the earlier calyx cups 

 closing. The Gano trees in this orchard were bearing from 1,000 to 

 2,200 apples, the other varieties considerably less, with an average 

 for the checks of 700 apples. 



Poison Used. The poisons used were a standard lead arsenate (L.A.) 

 and a new compound (N. C.)' each used in two strengths; five pounds, 

 and two and one-half pounds, to the hundred gallons. The N. C. 

 did not prove efficient, especially in the two and one-half pound 

 strength, and allowed too many w^orms to escape. These spread to 

 the L. A. rows in the second brood, and lowered the apparent effici- 

 ency on the side worms. In the Woodbury orchard, where a greater 

 amount of the two and one-half pound strength was used, and where 

 the trees were bearing a very light crop, this effect was especially no- 

 ticeable, often reducing the apparent efficiency on the total wormy to 0. 

 This is only apparent, however, the real efficiency on side worms was 

 no doubt as high as in any other case, as the remarkable calyx effici- 

 ency shown under these conditions indicates that very thorough spray- 

 ing was done. 



1 It was through the financial assistance of the manufacturers of this compound 

 that this spraying experiment was undertaken. 



