118 Early Work in North America 



pear blight, but admitted no " genuine remedies " existed. Germi- 

 cides and sprays were being experimentally investigated. Certain 

 pear varieties were known to be less blight-susceptible than others. 

 Immediate removal and burning of affected branches had been 

 early recommended, as well as clean orchard culture and other 

 practical measures. Smith accredited ^°^ both Burrill and Arthur 

 Vv^ith observing blossom-blight caused by the bacteria; and Arthur 

 suggested that the bacteria entered through the nectaries, a con- 

 clusion later proved by M. B. Waite when establishing the insect- 

 transmission of the disease. Smith's comparative account ^°" in 

 1885 of the work of Burrill and Arthur in pear blight conformed 

 substantially to his more elaborate description of fourteen years 

 later, when, to the contributions made by them, he added the 

 results obtained by Waite by 1899."^ 



In 1886 Burrill, with the use of pure culture inoculations, was 

 studying "A Disease of Broom-Corn and Sorghum." "* Interest 

 in this study is heightened by the fact that Waite assisted him in 

 part of the investigation. In July bacteria were believed found 

 associated with the tissues and in August some unsuccessful inocu- 

 lation experiments were performed. A pure culture of a bacillus 

 was saved and the next year Burrill believed that he had repro- 

 duced the disease with the artificial culture. With material from 

 diseased stalks Waite commenced experiments on young plants. 

 At the eighth meeting of the Society for the Promotion of Agri- 

 cultural Science, Burrill reported on the disease. 



Waite graduated in 1887 from the University of Illinois and 

 spent a year as an assistant to Burrill. His work in pear blight 

 began later after becoming connected with federal agricultural 

 work. He made " successful inoculations of Bacillus amylovorus^ 

 using modern methods and pure cultures obtained from poured 

 plate colonies. . . ." He and Smith became acquainted in 1888, 

 perhaps earlier, while both men were employed in the Section 

 of Vegetable Pathology of the United States Department of 

 Agriculture. 



^"^ Centralblalt f. Bakt. II, 5 (8): 277, 1899. 



^°^ E. F. Smith, Recent literature concerning pear blight, Michigan Horticulturist 

 1 (2): 34-36. 



^°^ Centralb. f. Bakt. II, 5 (23): 813-814. Describes experiments begun at 

 Washington in 1894 and which Smith watched, inoculations and results. 



"•** Proc. Soc. Prom. Agric. Sci., 30-36, 1887, at p. 32. 



