DAIRY AND SEED IMPROVEMENT MEETINGS. 257 



Some years ago I attempted to collect all these named species 

 of blackleg bacteria from Europe and Canada and then to 

 make a careful, comparative study of them and those found in 

 Maine. It has been a long, laborious task, but the work has 

 recently been completed. I regret to say that, although cul- 

 tures were obtained from the laboratory in which the species 

 named in Germany was originally studied, they were not patho- 

 genic, and I am convinced that they were not the same as origi- 

 nally described there. All the other named species were essen- 

 tially identical with each other and with those isolated from 

 diseased plants in Maine. Therefore, from a practical stand- 

 point, I believe that we are warranted in concluding that, no 

 matter from what source this type of disease comes to us, the 

 control measures already outlined will be effective in eliminat- 

 ing it. Before leaving this subject I wish to emphasize the 

 fact that any potato grower who tolerates blackleg upon his 

 fields is subjecting himself to unnecessary loss and expense. I 

 wish I might be able to say the same about a number of other 

 potato diseases, but unfortunately this is not the case. 



Powdery Scab. 



In view of recent history no discussion of this kind would 

 be complete without some mention of powdery scab. We are 

 exceedingly thankful that, from the standpoint of the country 

 as a whole, it is a much less serious trouble than we were led 

 to believe at first. Even though the lesson in some instances 

 has been an expensive one, the powdery scab agitation has 

 served a most useful purpose, for it has set people to thinking 

 and to observing. Now they are seeing things and appreciating 

 things on their own farms which previously they thought 

 existed only in the imaginations of certain impractical, scien- 

 tific men who were casting about for some good excuse for 

 drawing a salary. 



Powdery scab is now known to occur in Aroostook, Penob- 

 scot and Washington counties in Maine, but is almost exclu- 

 sively confined to the former. In New York, it is only in Clin- 

 ton and Franklin, the two most northern counties. In Minne- 

 sota, it is confined to the three most northeastern counties, St. 

 Louis, Carleton and Lake, either on or near Lake Superior. 



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