Jones—Relation of Soil Temperature to Disease in Plants. 437 
relation of amount of infestation, moisture, chemical reaction, 
temperature and physical and mechanical composition, reaching 
the conclusion that of these factors soil temperature is undoubtedly 
the most important.) 
Work in Progress, Upon which no Publications or Only Pre¬ 
liminary Notes have Appeared 
7. The relation of soil temperature to the development of the 
root tubercles of legumes, caused by Bacillus radicicola. F. ft. 
Jones and W. B. Tisdale. In progress 1917 to date. Undertaken 
in cooperation with the U. S. Department of Agriculture, Bureau of 
Plant Industry. Manuscript submitted for publication in an early 
number of the Journal of Agricultural Research. 
8. The relation of soil temperature and soil moisture to the de¬ 
velopment of the yellows disease of cabbage, caused by Fusarium 
conglutinans. W. B. Tisdale. In progress 1917 to date. See pre¬ 
liminary note, Phytopath. 10: 63. 1920. 
9. The relation of soil temperature to the cankering of potato 
stems, caused by Rhizoctonia (Corticium vagum). B. L. Richards. 
In progress 1917-1919. Completed manuscript filed as doctor’s 
thesis in the library, University of Wisconsin. Abstract presented 
at the meeting of the American Phytopathological Society, Janu¬ 
ary 2, 1920. Undertaken with partial financial support of the 
U. S. Department of Agriculture, Bureau of Plant Industry. In 
connection with this, Dr. Richards and Dr. F. R. Jones determined 
the relations of soil temperature to the parasitism of this fungus 
upon seedling stems of certain other hosts, including bean, pea, 
and cotton. (To appear in the Journal of Agricultural Research.) 
10. The relation of soil temperature and other factors to the de¬ 
velopment of the wilt disease of tomato, caused by Fusarium lyco- 
persici. E. E. Clayton. In progress 1917-1920. Completed 
manuscript filed as doctor’s thesis in the library, University of 
Wisconsin. See also preliminary note, Phytopath. 10: 63. 1920. 
The correlation between air temperatures and soil temperatures 
has been studied, also the relation of these to variations in soil 
moisture. In cooperation with E. C. Sherwood, attention has also 
been given to the influence of soil reaction. See thesis for M. S. 
