94 



usually enter the side of the fruit, producing the familiar 

 side-wormy apples. Two broods appear to be the rule in the 

 northern fruit growing seijtion of the United States. 



With the above summary of the habits of this insect in 

 mind, it is easy to see that there are three well defined 

 periods when applications of poisons may be more or less 

 effectual. 



The first comprises the week or ten days after the drop- 

 ping of the white petals or bloom, and during which the 

 much smaller green calyx lobes remain open and the young 

 apples upright in such a condition that the calyx cavity can 

 be more or less filled with poison. 



The second period is about three weeks after blossoming 

 and is the time when the young codling moth larvae or apple 

 worms hatch, begin feeding and enter the fruit. 



The third period is the latter part of July or early 

 August and is of especial importance because the small 

 caterpillars of the second brood, the young apple worms are 

 then hatching and feeding on the leaves or entering the fruit. 



We were desirous of obtaining some information as to 

 the actual value of poisoned sprays applied during these 

 different periods, and also wished to ascertain ?iow many 

 were necessary to control the apple worm under average 

 conditions. Experiments were begun in 1909 and continued 

 through 1912. The work was planned along practical lines, 

 so far as possible, and special pains taken to secure only 

 fairly representative trees in orchards kept in good horti- 

 cultural condition. Invariably the spraying outfit and the 

 men on the place were employed, the entomologist contenting 

 himself simply with explaining his methods and insisting 

 upon reasonable thoroughness in treatment. It only re- 

 quired, for example, one minute and three gallons of spray 

 material to treat a tree 15 feet high with a power outfit 

 equipped with two lines of hose. The experiments were 

 conducted in four well separated localities, while the trees 

 selected were of the standard varieties, being Baldwins, 

 Greenings, Northern Spy and Ben Davis. The diversity of 

 season, location, equipment and men and the different va- 

 rieties used for the tests, prevent these experiments being 

 classed as local or exceptional. The spraying was invariably 

 given as soon as possible after the dropping of the petals, 



