STATE HORTICULTURAL SOCIETY. 213 



Prof. Burrill found it is on the young trees that the blight works 

 most easily. In the summer, during the time that he was making 

 these experiments there were a good many thunder-showers; he could 

 not find that the blight worked any more rapidly or slowly during the 

 thunder showers than before — couldn't see that they had any effect. 

 Later he found that the blight sometimes occurs in winter as well as 

 in summer, although to less extent. 



The bacteria that produces this blight is perhaps ^j^so of an inch; 

 from this fact it is not surprising that not much has been found out 

 by the use of the old microscopes, but the microscopes have been so 

 much inii^roved that we can get a pretty distinct view of them. 



Mr. Pearce. I would like to ask if they attack the sound tissues of 

 a tree? 



Prof. Seymour. Yes, they attack healthy trees if there is a break in 

 the bark, if the bark is rubbed off to allow them to enter. The tree is 

 not diseased before they get in. They grow in healthy tissues and 

 make them diseased. The cells of the bark contain starch, stored up 

 in little granules as food for the tree. Healthy cells are full. When 

 the bacteria get in, they destroy the starch grains and starve that 

 part of the tree. They can not enter through the bark when that is 

 unbroken, but they may get in through the flowers in some other way. 



On motion, the meeting was then adjourned until 7 o'clock p. m. 



EVENING SESSION. 

 Wednesday, January 20, 1886. 



The meeting was called to order at 7 o'clock by President Smith. 



The following lecture was then delivered by Prof. A. B. Seymour, 

 of the State University at Madison, Wisconsin : 



SOME FUNGUS DISEASES OF SMALL FRUITS. 



3fr. President, Ladies and Gentlemen: 



Before speaking of any particular disease, I wish to show how and 

 why fungi produce disease in plants. It is well known that the green 

 coloring matter occurring in all our common plants has the power of 

 converting inorganic matter taken from the soil and air into food 

 materials for the plant. All plant food and indii'ectly animal food is 



