130 STATE BOARD OF AGRICULTURE. 



Careful observations covering periods of several years have been made 

 in a number of States and it has been well established that a period of 

 six weeks may elapse between the time of the first specimens of the first 

 brood appear, and the hatching of the last individuals of that brood. 



While many fruit growers give their trees only one application after 

 the fruit sets, a majority of them follow this application with another 

 two or three weeks later, and then spray for the second brood the first 

 week in August. This practice leaves six or seven weeks between the 

 date of the last spraying in June and tlie first spraying in August, and 

 as the larvae of the codling moth will be hatching every day during that" 

 period we may expect during the latter part of July a large proportion of 

 the worms will be able to enter the apples in spite of the poison applied 

 six or seven weeks before. We are convinced that in sections where 

 this insect 'is plentiful, the only safe method is to spray or dust the 

 trees as often as once in two or three weeks from the time the fruit 

 sets until the middle of August. This means that at least four treatments 

 should be given winter varieties of apples after the fruit has set, and 

 if the worms have been plentiful and the season is rainy so that the poison 

 is washed off: as many as six applications may be worth while. 



During the spring of 1920 a circular covering the above points was 

 quite generally distributed through the press and by mailing copies 

 to individuals. 



The Control of Apple Scah. The past two seasons have not been favor- 

 able for the development of the fungus which causes "scab" on the fruit 

 and foliage of apples, but there was sufficient development of the di- 

 sease to show that good fruit cannot be grown without spraying. 



In some sections it was cold and wet at about the time the buds opened 

 and there was conclusive evidence of the value of the pre-piuk spray. 

 If we make the first application as soon as the first sign of growth 

 shows and repeat the application often enough to keep the leaves and 

 fruit covered, we will be sure to have foliage and fruit free from this 

 disease. The June drop is sometimes largely due to the attack of apple 

 scab. 



As a rule, jt will be safe to make but one application before the blos- 

 soms open but if ten days have elapsed after the pre-pink spray and 

 the ]ietals have not opened it will be well to make a second a]>plication. 

 We would then spray within a week after the petals have fallen, and 

 re]>eat it every two or three weeks up to the first of August. An ap- 

 jtlication about the middle of August would also be worth while for 

 Avinter .varieties that are especially subject to attack, if the weather 

 is wet and favorable for the development of the disease. 



We are glad to report that not only was spraying never more general 

 than it has been this year in the commercial orchard section, but it has 

 never been as thorough and the results will certainly be seen in the 

 quantity as well as the quality of the fruit sold this autumn. 



The Cavker Worm. Although seldom if ever entirely absent from the 

 State, the Caidcer worm has not been generally distributed for a num- 

 ber of years. In the sjtring of 1920 it did more harm than for 25 years, 

 and its work was quite noticable in most of the counties in the southern 

 half of the State. It was generally in orchards that had not been sprayed 

 and 'VAhen its presence was noted it was too late for etfeclual spraying. 

 These orchards had the appearance of having been burned. In a num- 



