Appendix. 149 



female deposits her eggs in the calyx just as the apple is forming; in a 

 short time -the egg hatches and the worm begins its damage. The first 

 spraying to be effective must occur before the calyx of the apple closes 

 and before the egg hatches; otherwise the poison cannot destroy the 

 worm. 



The bloom being well off the trees, vigorous spraying with the gasoline 

 spray pump enables us to go over our orchard of one hundred and sixty 

 acres in ten days. Should a rain occur immediately after spraying, we 

 spray again at once. Should we have no rain for the three weeks, we 

 then spray once again; and every three weeks during the season we 

 cover the trees with their coat of poison. Again the gasoline spray 

 pump is a power, in that rapid work is accomplished. In the spring when 

 it is necessary to spray for the first deposits, the period is very short 

 between the falling of the bloom and the closing of the calyx, and it is 

 impossible to thoroughly spray a large orchard with hand pumps. 



Then we have the spring rains to combat. If our first spraying has 

 been effective, we do not notice much damage until the broods of August 

 and September appear. The orchard may be sprayed in the spring and 

 early summer, and be free from the worm to the beginning of August, 

 and if neglected for the rest of the year, a great amount of fruit is de- 

 stroyed. As a rule our success in spraying has been in going over the trees 

 for the last spraying the first or second week in September. 



Good returns follow well directed efforts. Four good rules are: 



First — Be sure your poison is good. 



Second — Thoroughly agitate, as Paris green will settle to the bottom 

 of the tank like sand, and your work is lost. 



Third — Apply the poison at the proper time. 



Fourth — See that your work is thorough and success is yours. 



coxcr.usioxs. 



The codling moth is our most serious apple pest. 



It is likely to be a serious pest wherever the apple can be successfully 

 grown. Apple-growing regions now free from it are not likely to long 

 remain so. 



The average percentage of fruit injured by the codling moth is not 

 greater in Oregon than in other apple-growing regions. 



There are but two annual broods — not three or four, as has been stated. 

 Owing to irregularity of development these broods overlap so that larvae 

 may be found in fruit from the time the first wormy apples occur in spring 

 until after the fruit is gathered. 



In the Willamette Valley, there appears to be no relation between the 

 blossoming of the apple trees and the time at which the moths appear. 



The eggs are deposited principally on the surface of the fruit and not 

 in the calyx. At Corvallis egg-laying does not begin until towards the 

 end of June. It probably does not occur when the evening temperature 

 falls much below sixty degrees, and is probably most active when such 

 temperature is above seventy-five to eighty degrees. 



