192 STATE BOARD OF AGRICULTURE. 



Tree I gave the following results. 1 1 was in the same orchard but more distant 

 from tree III than tree II. There was little scab. 



TREE I. SPRAYEn. 



Yield 12 bu. 



No. of apples 1,883 



Not wormy 1.750 



Wormy 133 



Per cent wormy 7 OG 



This shows great superiority in salable fruit in the case of the sprayed orchard. 



Counts made from two trees in an unsprayed orchard, the one in which we 

 had banded trees, were made on October 8. Two Northern Spy trees were selected, 

 as this was the only variety common to both orchards, which had trees of approx- 

 imately the same size, and also because the Spy is standard in Michigan. The 

 outputs of these two trees were classed together, being rather light. The result 

 was as follows: • 



TREES IV .\Ml V. TNSl'K.WKI). I\ I'XSl'U.V YKl) ()l!(ir\ltI)S. 



Yield 71/0 bu. 



No. of apples 1,054 



Not wormy 114 



Wormy 940 



Per cent wormy 89.3 



There was much scab on the fruit and many windfalls. This helped to pull 

 down the yield very appreciably. The fruit in no case was cut open, but judged 

 as well as possible from outside appearances. 



THE riMKi) r.i:()<)i>. 



The work of the present season seems to indicate two annual generations rather 

 than three. It was at first thought that the presence of young larvae in the 

 apples in October, which had appeared just when the third brood would have 

 been due, was very suggestive of a third brood, but the counts made in 1904, 

 showing the waves of pupation, etc.. do not bear out this theory. If there were 

 a third brood, one would expect to find a corresponding wave of pupae and adults, 

 furthermore, in our observations, the October larvae Avere not of a uniform size, 

 grading instead from very small individuals to those of considerable size. The 

 fact remains, however, that larvae do enter the fruit late in the season, working 

 in considerable numbers even after the apples have been packed and sold. 



KATUKAL ENEMIES. 



Besides a number of parasites which infest the codling-moth, we find here a 

 fungus disease (Isaria farinosa) which was separated out and grown in pure 

 culture by the writer during the season of 1903, and which fungus killed other 

 larvae that were brought in contact with the culture. An attempt to collect winter 

 cocoons called attention to the fact that birds play an important part in keeping 

 down the insect. Most of the cocoor.s found in the spring were concealed beneath 

 flakes of loose bark, and in almost every case, a hole through the bark flake to 

 the inside of the cocoon, showed an opening through which the larvae had been 

 extracted. 



Such pierced cocoons are the common thing in our orchards, especially is this 

 true in all cases where they have been placed high enough to be above the snow 

 line. Those placed below the level of the snow are more or less i)rotected and 

 are more likely to escape. For this reason it will be good practice to scrape off 

 in the fall all loose flakes below the level of the snow. . 



Some parasitic hyraenoptera were bred from cocoons collected from under the 

 bands. 



Large numbers that winter under fences, brush, etc , are doubtless eaten by 

 shrews, which are quite plentiful in Michigan orchards. 



