out in this country for the black rot of grapes, the apple scab 

 and the late blight of potatoes. The results were so satis- 

 factory that within a decade it had become the generally recom- 

 mended and accepted fungicide for most of the fungous diseases 

 of our crops. It continued to hold this pre-eminent position 

 until about 1906, when, through a discovery by Cordley in 

 Oregon, lime-sulfur was introduced as a substitute for Bor- 

 deaux in the summer spraying of apples. The work of Wallace 

 in New York during the years 1909 to 1912 on the control of 

 apple scab by the use of lime-sulfur brought about the all but 

 complete abandonment of Bordeaux as a fungicide for apple 

 scab in that State. Work in the other apple-growing sections 

 of northeastern United States, Canada and the Pacific Coast 

 completely confirmed the results obtained in New York, so 

 that within five years lime-sulfur had largely replaced Bor- 

 deaux as a summer spray for apples in most apple-growing 

 regions in the United States and Canada. 



It is interesting to observe in passing that experimental work 

 on spraying as a field practice in the control of plant diseases 

 and pests in thjs country was at first almost entirely in the 

 hands of horticulturists. The reasons for this are not far to 

 seek. Plant pathologists as such were few and their efforts 

 were largely confined to investigational work in the laboratory. 

 They were busy with studies on the nature and life history of 

 the organisms that caused these diseases. Horticulturists were 

 far more numerous and were, from the nature of their work, 

 most closely associated with the grower in the practical problems 

 in the orchards and fields. Disease and pest control was looked 

 upon as a practical problem rather than a scientific one. Plant 

 pathology as a profession had little or no standing, while 

 horticulture was generally recognized as the most advanced 

 and progressive of agricultural professions. 



The decade from 1900 to 1910 saw the entrance of the prac- 

 tical plant pathologist into the agricultural field in this country. 

 The first university chair of plant pathology was established 

 in America in 1907. Before the end of the decade plant pathol- 

 ogists as such were appointed to positions in many of the 

 agricultural colleges and experiment stations in this country. 

 Immediately they began to claim their rightful place in agri- 



