CHAP TE R IV. 



An Account of Diseases which have previously affected the 

 Potatoe, and the Remedies that have been found efficacious. 



IN finding materials for this chapter I must necessarily 

 confine my attention principally to English publications, as 

 English writers on agriculture have noted and marked the 

 nature, effects, and cure of the various diseases which have 

 affected this root, with more exactness and precision than 

 have characterized American writers on this subject. 



The potatoe is subject to disease at a very early period of 

 its existence, not merely after it has developed its leaves and 

 stems, but before the germ has risen from the sets. The 

 disease which affects the p,lant is called the curl, from the 

 curled or crumpled appearance which the leaves assume 

 when under the influence of the disease. What the imme- 

 diate cause of the disease is, it is very difficult to say ; but 

 the puny stems and stinted leaves indicate weakness in the 

 constitution of the plant, and, like weak animals affected with 

 constitutional disease, the small tubers produced by curled 

 potatoes, when planted, propagate the disease in the future 

 crop. The curl is so well known by its appearance, and the 

 curled plant so generally shunned, as seed, that the disease is 

 never willingly propagated by the cultivator ; still there are 

 circumstances in the management of the tubers which induced 

 the disease therein. The experiments of Mr. T. Dickson 



