368 Chief of a Laboratory of Plant Pathology 



be issued. Add to this the regular diagnostic and remedial services 

 furnished plant growers from every state of the Union, and one 

 comprehends in brief compass its contribution to plant pathology 

 and bacteriology during Smith's tenure. During these years, crop 

 losses from bacterial and fungous diseases ranged from two to 

 ninety-five per cent annually. First, the etiology of these maladies 

 had to be understood, and proof of how infections start and are 

 transmitted were often necessary preliminaries to working out 

 methods of control or prevention, and remedies. If infections 

 were transmitted by insects or through soils or on the seed, it 

 was often as valuable to know these facts as to know the path- 

 ogenic organism responsible for the malady. Fundamental, never- 

 theless, was the isolation by pure culture technique of the organism, 

 and each disease was studied from every available aspect. 



In 1902-1903 ^^ Smith found on Japanese plums in Michigan a 

 disease which he proved to be caused by Bacterium pruni EFS. 

 He worked on this disease for twenty years, yet never published 

 a full account of the organism. His first paper, entitled the same 

 as his preliminary note in Science, was presented before the sixth 

 meeting of the Society for Plant Morphology and Physiology. 

 Dr. Spalding was then its president. At this meeting Smith offered 

 also his " Completed proof that Ps. Steivarti is the Cause of the 

 Sweet Corn Disease of Long Island." At the December 1903 

 meeting of the Society he began to discuss the bacterial origin and 

 the parasite of the tumor of " The olive tubercle," ^* due to Bac- 

 terium Savastanoi EFS, the results of study begun that year with 

 James Birch Rorer. 



In 1903 Smith published his Bulletin 29, " The Effect of Black 

 Rot on Turnips," '^'^ a series of photomicrographs accompanied by 

 an explanatory text. 



For the next several years he studied mainly bacterial diseases 

 of plants, work aimed at preparing to place in written form 

 various portions of his three-volume monograph. Bacteria in 



^^ E. F. Smith, Observations on a hitherto unreported bacterial disease, the cause 

 of which enters the plant through ordinary stomata, Science n. s. 17(429): 456-457, 

 March 20, 1903; Synopsis of researches, op. cit., 31-32; Fifty years of pathology, 

 op. cit., 29; Beobachtungen ueber eine bis dahin unbekannte, durch Bakterien 

 verursachte Krankhcit, die durch die gewohnlichen Stomata in die Pflanze eindringt, 

 Centralhlitt f. Bakt. etc., II, 10(22/23): 744-145, 1903. 



''* Science n. s. 19(480) :4l6, March 11, 1904. 



" Issued Jan. 17, U. S. Bur. of PI. Ind., pp. 9-20. 



