BLACKLEG. 319 



tubers were imported from England. In A'ermont Prof. H. A. 

 Kdson states that it has only been observed on one farm where 

 it was first introduced with the seed and reported by Doctor 

 Jones in 1006. "■■' In Mrginia Prof. T. C. Johnson first reported 

 the existence of the disease to the writer some over a year ago, 

 and writing on September 27, 1909, he says : "The "blackleg' 

 is becoming somewhat g:^neral in this section of \'irginia." 

 There can be no doubt as to the identity of the disease in A'ir- 

 ginia and Maine as Professor Johnson is perfectly familiar with 

 its appearance as it occurs in the field in both states. 



In [Maine, as has already been stated, the disease is not 

 uncommon, but as a rule it occurs only as an occasional, 

 isolated affected stalk scattered over the fields, though several 

 cases were found during the two wet seasons of 1907 and 1909 

 where from 5 to 15 or 20 percent, of the plants were affected. 

 These latter instances represented, with one exception, small 

 fields of from one to 5 acres. 



The similar appearing trouble wdiich Plarrison has described 

 in Canada he stated had been found throughout the Province of 

 Ontario, its presence had been reported from Nova Scotia, New 

 Brunswick and Quebec, and one case reported from the North 

 \A'est Territory.t 



Economic Aspects. 

 There is little evidence to show that blackleg has caused or 

 is likely to cause serious and widespread losses on Maine potato 

 fields although its occurence appears to be on the increase. 

 While one of the worst cases found in 1909 was on well- 

 drained, elevated land, the soil was quite wet on account of 

 excessive rainfall throughout the season. So far as observed 

 it is only to be feared as a serious pest in this section upon 

 low, wet lands or on higher ground during abnormally wet 

 seasons. However, in localities where the disease is prevalent 

 during wet seasons, occasional aflfected hills are found upon 

 the dryer soils and during years when the rainfall is not exces- 

 sive. 



* Sec p. 310. 

 1 1. c. p. 35. 



