442 BOARD OF AGRICULTURE. [Pub. Doc. 



cannot be controlled ; Avherea.s, in iinder-i»la>ss culture there is 

 little difficulty in controlling these conditions and preventing 

 such diseases. The application of the moisture absorb- 

 ent to asparagus plants has in some instances very percep- 

 tibl}^ reduced the rust ; and even the cover of an apple tree 

 is often sufficient to keep the dew oti' and render the plants 

 free from infection. With this idea in mind, tent cloth 

 crops have been tried with some degree of encouragement ; 

 although the exjiense of tent covers and the results obtained 

 from the same do not at present appear to be such as to 

 warrant their use except in special cases. Another element 

 which has a great bearing on the health of })lants, in general, 

 is i)r()per feeding. The influence which ])roper feeding and 

 cultivation has on the susceptibilitj' of crops to disease is 

 (juite marked. There is little doubt but that in many cases 

 time and money could be better spent in securing robust 

 crops by cultivation and feeding than in spraying sickly 

 ones. 



Tomatoes. 



Blight or Mildew (^Clados^mrium fiilvuiii^ Cke.). 

 This mildew grows on both outdoor and greenhouse toma- 

 toes. Infected plants show, on the under surface of the 

 leaves, a velvety, brownish-colored, downy mass. The ui)per 

 surface of the leaves turns yellowish and the edges become 

 curled. It propagates (juickly and freely by spores. The 

 method of preventing mildew in the greenhouse is to keep 

 down the moisture in the air and give the plants sufficient 

 light and ventilation. Massey, in the North Carolina Sta- 

 tion Bulletin No. 170, states that spraying with a weak 

 solution of potassium sulphide, and dusting the pipes with 

 a wash of sulphur and lime, completely prevented mildew. 

 The latter treatment, however, is probably the most effec- 

 tual. For out-of-door plants the best treatment would con- 

 sist in spraying with some standard fungicide. 



