234 BOARD OF AGRICULTURE. 



the fall, and others will be left over : so, if you find lettuce- 

 leaves ajQfected, do not let them be, but pull them off and 

 burn them. If you simply pull them off, these seeds will not 

 be injured. They will come out the next spring with full 

 force. 



Mr. Strong. The lecturer states that these spores are 

 perishable, unless they have a sufficient amount of moisture. 

 Now, it is known that this fruit-mildew does not prevail 

 until about August, when we have warm weather, and very 

 rapid generation. I would like to know how these spores 

 live from spring until fall. 



Professor Faelow. The spores that are preserved through 

 the winter will be those that germinate, and enter into the 

 plants when they appear above the ground. The threads 

 are found in the leaves and stems, from top to bottom. After 

 a while, when they have gained sufficient force, they burst 

 through ; but they do not grow much for a time : they 

 remain quiescent; but the next moist weather they will 

 develop rapidly. 



Mr. Steokg. You are not aware of the existence of the 

 disease until you see these spots on the leaf. The fungus 

 may nearly fill up a grape-vine, and not do much harm : but, 

 the moment it has acquired force enough to break through 

 into the air, it seems to have attained much greater vigor ; 

 and, simultaneously with breaking through on the surface, 

 you will see a wilting and destruction of the leaves. 



Professor Stockbeidge. We have found an application of 

 sulphur destructive to the fruit-mildew, when it has broken 

 through, and becomes visible to the naked eye. 



Mr. Paul. Is there any remedy for the fungus on the 

 grape-leaf? I am not a judge of these matters; but I will 

 state a fact, which, by analogy, may apply to the question 

 now under consideration. A neighbor of mine picked the 

 leaves off of his strawberry-plants, and none of the berries 

 ripened. I have seen on my own vines, where from some 

 blight the leaves shrivelled and dropped off, that the grapes 

 never matured afterwards. 



Mr. FiSHEE. Some grape-growers have pulled the leaves 

 from their vines to let the sun in ; and the result has been 

 exactly what any man of sense might have expected. Grape? 

 never ripen except in the presence of the upper leaves. 



