I 9°5\ Journal of the Mitchell Society. 71 



the national department of agriculture, the vigorous cam- 

 paign of farmers' institutes, farmers' reading circles, farmers' 

 extension courses, and the extended use of farmers' periodi- 

 cals and agricultural papers have served to bring the latest 

 discoveries of science to the use of him who will heed. As is 

 to be expected, it is the man who most closely studies his 

 business, he who has most at stake, the large specialist in the 

 culture of any crop, who first embraces the offered aid. The 

 orchardist or vineyardist leads the way in the adoption of new 

 methods and new machinery. The revolution looking toward 

 recognition of the value of plant treatment is now so thor- 

 oughly inaugurated that the treatment of such diseases, both 

 insect and fungous, in the case of fruit and trucking crops is 

 of general occurrence. The movement, too, is world-wide. 



The practical outcome of all the investigation and propa- 

 ganda up to the present time is that many hundreds of plant 

 diseases have been recognized; for a hundred or more have 

 been prescribed remedial or preventive measures, many of 

 which are eminently successful; witness, the treatment of 

 cereal smuts, the peach curl, the grape black rot, the powdery 

 mildews. The saving occasioned by any one of these, as is 

 true of scores of others, would amply suffice to pay all the 

 expense of investigation and propaganda incurred in the 

 development of the whole field of plant pathology. By oat 

 smut alone the estimated damage in the United States yearly 

 is $26,766,166, a loss avoidable by an annual expenditure of 

 less than four cents an acre. The saving actually made in 

 Dakota, Minnesota and Wisconsin in one year is placed at 

 $5,000,000. 



The future problems of plant pathology are manifold. 

 The period of growth must continue long before the work 

 now undertaken is done. Many diseases of even the culti- 

 vated plants are not yet recognized. The diseases of wild 

 plants, particularly the weeds, must too be studied to ascer- 

 tain the possibility of intercommunication of diseases between 



