FlORIPA ANI-) C^AIirOKNIA LAliOKATOIUHS 263 



of a Division ot Soils in the Department of Ai;riculture. He had 

 studied in South Carolina diseases and insect ravages of the cotton 

 plant in relation to soil conditions, and his knowledge of agri- 

 cultural chemistry further qualihcd him for such an investigation. 

 Soils research was then emerging into more dehnite scientific 

 prominence. During 1892 the Expcrinie)it Stiition Record by 

 editorials *^- had recommended to students more research in plant 

 diseases caused by bacteria and also cooperative soils investigations 

 of the type begun by the Department of Agriculture and the 

 Maryland station a^id Johns Hopkins University under Whitney's 

 leadership. 



Whitney offered to study with Smith a few Maryland localities 

 where healthy and diseased peach trees were in a close range of 

 proximity. Top-and-subsoils bearing diseased trees were to be 

 examined both in the orchard and from soil samples in the 

 laborator)'. The theory was that changes in the "texture of the 

 soil around a peach-tree might change the physical conditions of 

 growth sufficient to lower the vitality of the tree and render k 

 more liable to take the disease." Conversely, factors leading to 

 increased disease-resisting vitality were to be studied. Smith 

 believed that the contagious nature of the disease was now " well 

 established," *^^ and the results of his experiments with chemical 

 fertilizers were known to him, though not fully published. He 

 had not solved the problem and much work had been done. It is 

 likely that no collaboration ever took place. But, if it did, Smith 

 learned more of soil chemistry and soil physics and related this 

 knowledge to his interest in the nutritional requirements of plants. 

 In his study of the South Carolina watermelon disease, further- 

 more, he might have made some use of the knowledge. 



On July 1, 1894, from Monetta, South Carolina, he advised 

 Galloway: 



The watermelon fungus turns out to be one of the most interesting 

 things imaginable. ... It is no germ but a fungus! Of this I am now 

 certain, having examined 21 vines microscopically in a good many parts 

 of root and stem and having found this abundant in every case and in 

 the early stages of the disease, i. e., as soon as the leaves begin to wilt 

 and before stems or roots show any external signs of injury. The symptoms 



'-3(10): 665-670, May 1892; 4(2): 111-113, Sept. 1892. 

 *' The chemistry of peach yellows, pt. 1, op. at., reprint, 14. 



