228 ANNUAL REPORT OF THE Off. Doc. 



ties, and if used when (lie fruit is nearing mature size it tends to 

 aid in the coloring, and preventing the manilia, or brown rot which 

 in some seasons causes heavy loss. 



How Often Shall We Spray and When 



Ordinarily three times is enough, occasionally four times is bet- 

 ter. 1. Either in Ihe fall as soon as the petals drop, or early in 

 the spring before the buds expand sufficient to be injured. For 

 apple, I believe the fall spraying is the best. We generally have 

 more time, the weather is usually more favorable, we are not troubled 

 with such strong winds. In the spring we frequently have strong 

 northwestern winds for a week or ten days at a time, and very few 

 days with the wind south or southeast. Thus we often find it diffi- 

 cult to spray the tree on both sides. Fall spraying has another 

 advantage, we catch many of the lice crawling about having no 

 protection and so are easily destroyed. And the tree suffers less 

 than if they were feeding upon it during late fall and favorable 

 weather in winter. For peach I prefer spring spraying, as one 

 application answers for the Scale, and as fungicide to prevent the 

 leaf curl. 



2. Spraying depends upon conditions. Some seasons we have 

 an epidemic of Aphis, like the season of 1909 when the foliage and 

 fruit of the apple was seriously injured all over the country. For 

 these pests we spray Avith one of the emulsions, just as the buds 

 begin to open and the small leaves are forming. 



3. Spray, as soon as the petals drop, or inside of ten days. At 

 this season the calix cups are standing erect and open in the most 

 favorable position to receive the poison. At this time by spraying 

 from above downward with a good pressure some of the poison will 

 be forced into the cups, but if left later the sepals close and no 

 poison can enter. This is important as from seventy to eighty per 

 cent, of the larva of the codling moth enters the fruit from the flower 

 end. If this contains poison the small worm takes its first meal 

 and perishes. 



4. Spraying should be about twenty days later. Many bulletins 

 recommend ten daj's after the petals drop, but this is too early, as it 

 is seldom that any young larva are hatched before July, as the life 

 history of the insect shows. The larva passes the winter in the 

 cocoon in some secluded place. During May the larva opens the 

 end of the cocoon and spins a silken tube to the surface, then re- 

 turns to the cocoon with its head to the opening, and sheds its 

 coat, and transforms into a pupa, which is its dormant stage, dur- 

 ing w'hich time it goes through most wonderful changes from a 

 worm into a winged moth. This transformation averages about 

 sixteen days, time depending upon the w^eather. At the end of 

 this time the puj)a wriggles out of the cocoon, Ibis takes place fnmi 

 the 10 th to the 20th of June. If the weather is warm the moth 

 begins laying eggs in five or ten days, and die in a couple of weeks. 

 So the eggs are laid the latter part of June, or the beginning of 

 July. The eggs hatch in five or ten days. So it is seen that in 

 average seasons, the eggs do not hatch inside of a month after the 

 blossoms drop. 



Now^, as the eggs are laid, many of them upon leaves some dis- 

 tance from the apple, the small worm eats its first meal from the 



