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INSECTS OF THE YEAR IN COLORADO. 



By C. P. Gillette, Fort Collins, Colo. 



ORCHARD ENEMIES. 

 THE CODLING MOTH. 



(Carpocap-'in iioinoiiella Linn.) 



Oiir experiments and studies with tJiis insect for the past two years 

 have been chiefly for the ]Dnrpose of determining the comparative 

 vahies of early and late sj^raying-, the number of times that it is 

 advisable to spray, and the best poison to use. Besides conducting 

 ex]:)eriment3 in orchards near Fort Collins, the writer has visited 

 many orchards in the different apple-growing sections of the State 

 and has made counts of many thousands of apples in orchards sprayed 

 in different ways to determine percentages of wormy fruit. I have 

 found no reason to change the advice already given out to the 

 orchardists of the State, namely, to spray first as soon as the petals 

 are fairly well off', to repeat the spray in one week, and then make a 

 third s]iraying about the 4th of July. If the first and second spray- 

 ings are thorough the third will hardly be needed. The first spray- 

 ing, if thoroughly done at the right time, seems to be worth more 

 than all the applications that are made afterward. 



An examination of the fruit in October in many orchards that 

 were sprayed two or three times, as above directed, indicated that 

 less than 5 per cent of the fruit in such orchards was wormy at that 

 date. Unsprayed orchards near by would have from 50 to 95 per 

 cent wormy. 



Arsenate of lead has been used quite extensively in Colorado the 

 past season and with splendid results. xVlmost without exception, 

 those who used this poison the past summer say they will continue to 

 use it even if it is more expensive. Many orchardists have told me 

 that the}^ no longer fear any serious losses from the codling moth. 



PLANT-LICE. 



There are a few plant-lice that are serious orcliard jjests in Colo- 

 rado every year. The woolly aj)])le aphis {Schizonenra Janigera 

 Hausm.) is one of these. At the present time almost as much com- 

 plaint is made of it as of the codling moth. Treatment by orchardists 

 seems seldom to be satisfactory. Many who use tobacco about the 

 roots of the trees think they do not get good results. I should like 

 very much to hear of the experiences of the members of this society 

 in fighting this insect both on the roots and the branches of the trees. 

 What have you found to be the best treatment? 



The black cherry aphis {Myzus cerasi Fab.) and the green plum 

 aphis (Aphis jn'unifoUce Fitch) are much complained of nearly every 



