Page 40 



COMPLETE COVERING WITH THE MILDEW 

 Bud that was infected after making a healthy start in the spring 



few short feeders that draw substance 

 from the plant. 



The apple powdery mildew is no excep- 

 tion to this general rule. The parasite 

 grows over the surface of the affected 

 portions of the host, and so far as the 

 observations of the writer go it has a 

 very limited internal system. The exter- 

 nal growth of the fungus is, however, 

 very profuse, and affords a very ready 

 means of recognition. This mildew often 



BETTER FRUIT 



completely covers 

 the surface of young 

 shoots, and gives 

 them a decidedly 

 mouldy appearance. 

 Frequently there is 

 an abundance of a 

 white or greyish 

 powder which can be 

 very readily removed 

 from the mildewed 

 surfaces. This pow- 

 der consists in great 

 numbers of the sum- 

 mer spores of the 

 fungus. At other 

 times there are fewer 

 spores, and the fun- 

 gus has the appear- 

 ance of a felt-like 

 covering closely 

 applied to the twig. 

 When the twig is 

 completely covered 

 by the mildew the 

 leaves have a some- 

 what wilted appear- 

 ance, remain small 

 and are short-lived. 

 In this condition the 

 mouldy growth is abundant on both the 

 stem and leaves. When such infested 

 shoots are compressed in the hands they 

 emit a very strong mouldy odor. When 

 the mildew completely covers the shoots 

 it has a depressing effect on the growth. 

 Frequently the distance between leaves 

 on the stem is very much reduced, and 

 the growth of a whole season may be 

 compressed to less than a half inch. In 

 such cases the stem is usually thickened. 



February 



COMPLETE COVERING WITH THE MILDEW 

 Buds that were infected before expanding 



If, however, the attacked shoot happens 

 to be very succulent, such as a water- 

 sprout, the growth may be more normal 

 as to length, but will be spindling, and 

 the lower leaves die off, leaving only a 

 few of the younger ones at the tip. All 

 graduations are found between these 

 extreme types. 



The mildew does not confine its attacks 

 to the completely infested twigs, but 

 small infections occur on the under side 



BELLFLOWER FOLIAGE SPRAYED WITH IRON- SULPHIDE BELLFLOWER FOLIAGE UNSPRAYED. CRINKLED AND STUNTED 



THROUGH THE SPRING AND SUMMER APPEARANCE DUE TO MILDEW ON UNDER SIDE OF LEAVES 



