REPORT OF THE STATE ENTOMOLOGIST I909 63 



10,742 apples, obtained only T^.gi wormy. Another plot of five 

 trees received similar treatment with a mist spray and pro- 

 duced 24,316 apples, 1.88;^ being wormy. A third plot was 

 :<prayed like the preceding, except that it was drenched with a 

 coarse spray. It comprised four trees yielding 8109 apples and 

 produced 3.4^ wormy fruit. Conversely, a plot of six trees 

 sprayed in 1908 and producing only 21 to 930 apples each, 

 yielded but 2657 apples, ly/ being wormy. This latter approxi- 

 mates our results on trees bearing a very small crop. Almost 

 invariably such trees produced a markedly higher percentage of 

 wormy fruit than the more heavily laden ones. Gossard ['08] 

 gave a plot of four trees but one application. They yielded 4836 

 apples and an average of 95.91^ free from codling moth. Two 

 of these trees had a small crop, otherwise the percentage of 

 sound fruit would probably have been higher. One tree [Gos- 

 sard 09] produced nearly 99,^^ of sound fruit. Ball [07] as a 

 result of experiments conducted over a series of years, became 

 convinced that the first spray or the first and second sprays, namely, 

 the two given within a week or 10 days after the falling of the petals, 

 would kill 90^^ of the first brood in Utah, thus destroying many 

 of the progenitors of the second brood and, in addition, enough 

 poison remained on the foliage to kill some 74;/ of the second 

 generation of apple worms. He estimates that two early spray- 

 ings correctl}^ applied, are worth from 6 to 16 times as much as 

 three late ones. These two early sprays killed an average of 98;/ of 

 the worms of the first brood entering the calyx, and 97^ of those 

 of the second, an average of 78^' of the first brood entering the 

 sides of the apple and 52;^/ of the second brood attacking the 

 apple in the same Avay. ]\Ielander, apparently basing his recom- 

 mendations upon practical results over extended areas, has 

 recently come out most emphatically in favor of one spray, 

 claiming that this, if timely and thorough, will result in crops 

 practically immune from codling moth injury. 



It may be well to note in passing that Sanderson [08] as a 

 result of his extensive series of experiments, came to the con- 

 clusion that an early spray applied shortly after the blossoms 

 fell, and another approximately three to four weeks later, at the 

 time the codling moth eggs hatch, gave a maximum protection, 

 though he admits that the value of the second application is 

 doul)tful when not over 50^ of the fruit is likely to be infested 

 or unless a rain follows the first treatment. Obviously, the 



