350 MISSOURI HORTICULTURAL SOCIETY. 



The nature and causes of the potato rot now so prevalent in Michi 

 gan have been carefully investigated at the botanical laboratory of our 

 State University by Prof. y. M. Spalding and Erwin F. Smith, of the 

 'University of Michigan, and the latter gentleman has kindly furnished 

 the following article for publication in this report: 



THE POTATO ROT. 



The rot which has this season destroyed nearly one-third of the 

 potatocrop in Michigan, and a still larger per cent, in New York and 

 neighboring States is identical with that which caused the great famine 

 in Ireland in 1847. Michigan annually raises about 9,000,000 bushels 

 of potatoes, and though we are in no danger of starvation should the 

 entire potato crop be destroyed for a series of years, the loss of even a 

 third or a quarter of the crop bears heavily on the prosperity of the 

 farming community. The importance, then, of the potato crop, and 

 the probability of the return of the rot next year with Increased de- 

 structiveness should the season be wet, makes it desirable to give the 

 widest possible currency to sound knowledge of the nature of the dis- 

 ease and the measures which can be used to check its spread. 



Now, if I am to rely upon my own observations, instead of on the 

 theory that a potato, being a cutting, cannot improve or deteriorate 

 by selection or cuttting, I should say that the potato is greatly modi- 

 fied in quantity of yield and quality of product by conditions ot soil 

 culture and by the season. A variety may do remarkably one season, 

 or under certain conditions, and be almost worthless another season 

 or under different conditions, and the different 'varieties vary greatly 

 in their susceptibility to such modtfications and to get the best pos- 

 sible result we must uotonly have a variety which is good, but which 

 wall respond most readily to the most favorable conditions ; but such 

 a variety will almost invariably be subjected to corresponding deteri- 

 oration, if it has to contend with unfavorable conditions ; so the ideal 

 potato of experts in different locations or circumstances would not be 

 ths same, and would be sure to be different from the ideal potato for 

 general culture. — W. W. Tracy in Rural New Yorker. 



