362 Agricultukal Experiment Station, Ithaca, N. Y. 



Tlie total rainfall is 1.31 inches above the average for the month. 

 Most of the days during which no rain fell were cloudy and 

 wann, and the atniosj^here was moist. The first week in July was 

 also rather wet, but later the rainfall was considerably less. Such 

 conditions are generally supposed to favor the development of the 

 a(i>i)le-sciaJb (Fusicladiuni dt^mdriticum) and perhaps also other 

 fungi which work upon the trees. The rains also wash off the 

 materials wliioh are applied to the trees. Professor Atkinson has 

 examined diseased fruit taken from the orchard in which the 

 experiments were made and has found that a large part, if not all 

 of the injury done to the apples by fungi was primaiHy caused by 

 the apple-iscab fungus. The leaves were lalso more or less injured 

 but this was due partly to the action of other fungi as well as the 

 fusiclaidium. However, the latter may be considered as thewoi*st 

 pest and any treatment which will effectually check it A\ill 

 undoubtedly render the others harmless also. 



The life Mstory of the fungus has not been well determined. 

 IVIr. Fairchild, of the Division of Pathology at Washington, writes 

 me that the infections take place earlier in the se'ason than was 

 su'})posed; in fact that it is probable that the disease often obtains 

 a foothold e\en before the petals fall from the trees. The experi- 

 ments made here the past season tend to confirm the statement. 

 Tlie application of some fungicide before the buds of the apple 

 iypen will probably be as valuable as any later treatments which 

 may be given. When the fungus has once penetrated the plant 

 tissues, thei-e can be no efficient remedies for it. The fungicide 

 should be ujK)n the tree before the spors of the fungus germinate ; 

 and those of the ai>ple-seab occasionally seem to be growing even 

 before the opening of the first leaf buds. The apple-scab first 

 appears ujxyn the fruit in the fonu of grayish, slightly sunken 

 spots. These generalh^ are circular at first but when several grow 

 together their outline is irregular. As the spot enlarges the cen- 

 ter becomes quite dark, even black. At the edges may be seen 

 the epidermis or skin of the apple; it is loosened by the disejise, 

 and forms a light colored line which plainly divides the diseased 

 from the healthy tissues. 



