GENERAL PR A CTICE. DISEA SES. 



245 



have fallen, or when the leaves are about one-third grown, repeating at intervals of ten 



or twelve days once or twice, and afterwards at fortnightly or three-weeks intervals 



until the parasite is subdued. Special attention 



must be given to early treatment, always bearing 



in mind that the work is wholly preventive. 



Waiting until mildew gets hold signifies the 



spoiling of the crop, success resting with early, 



earnest workers, and those aiming at keeping the 



trees in health. Never forget that trees to perfect 



their current crops must be clean, and that for 



future ones it is essential that they store up 



sufficient material to insure vigorous blossom for 



setting. This is only possible by the presence of 



healthy foliage. 



Fig. 67. OlDIUM FABINOSUM (CoOKE) ON 



APPLE BLOSSOM. 



Natural size, showing abnormal condition, 

 namely : petals or floral leaves crumpled, 

 curled, and in parts contracted ; stamens 



Mr. Graig, of the Central Experimental Farm De- t rt ; ^ ^* v*^ by mycelia , 



the whole fructifying organs more or less 



partment of Agriculture, Ottawa, Canada, in Bulletin deformed. 



No. 10, under " Treatment of Apple Scab, Grape and Gooseberry Mildew," recommends 



a trial of the following, as a combined fungicide 

 and insecticide: "Carbonate of copper, 1^ ounce; 

 ammonia, 1^ pint ; Paris green, 1^ ounce; water, 

 25 gallons." 



Mildew. Trees infested with mildew appear 

 to be thickly dusted over or frosted with a white 

 or greyish- white powder. Every part of the tender 

 growths in bad cases is distorted, curled, swollen, 

 blistered, and sometimes blackened. Flower buds 

 and expanded flowers are often attacked. The latter 

 is so often unnoticed that an illustration will prob- 

 ably lead to close observation of fruit-tree blossoms. 

 The appearance of an attack of mildew on 



Showing : flocculence caused by the Oidium 



on filaments and anthers three stamens to blossoms and the tenderest terminal leaf shoots is 



the left; growth of fungus on style and ^ Qf & fine 

 stigma, as indicated by the flocculence two 



pistils on the right. the attack is severe that the mischief is noticed 



Fig. 68. Oromi GBOWING ON STAMENS AND 

 PISTILS OF APPLE. 



, 



that th 

 by ordinary observers. Yet the fungus grows with virulence upon the stamens and 



