172 Report of the Botanist of the 



All of the evidence obtainable goes to show that this bacterial 

 rot is not new, bnt that it is an old enemy whicb found unusually 

 favorable conditions for its development in some peculiarity of the 

 weather during the season of 1898. As yet, no attempt has been 

 made to determine the identity of the organism causing it. It 

 may be the same as the one causing the rot of onions and other 

 plants observed by Halsted^ in New Jersey. 



The weather records published by the New York State Weather 

 Bureau show that the rainfall in Orange Co. was excessive and the 

 temperature high from the middle of July to the close of August, 

 1898. At Middletown, which is on the edge of the onion district, 

 the dates upon which rain felP during this period were as follows: 



Rainfall at Middletown, N. Y., July 18 to August 2G, 1898. 



Date. Inches. Date. Inches. 



July 18 .31 August 11 .80 



July 19 .51 August 12 .08 



July 20 .90 August 16 .28 



July 21 1.85 August 17 1.31 



July 26 1.04 August 19 .41 



July 28 .09 August 23 3 . 08 



July 30 1.09 August 24 .42 



August 1 1 . 48 August 26 .52 



August 4 1.15 ■ 



Total 15.42 



In forty days 15.42 inches of rain fell and it was so evenly dis- 

 tributed over the period that the ground was almost constantly 

 wet. The onion fields, being on a low level, were frequently 

 inundated. In some cases whole fields were covered by the water 

 for a period of from 12 to 36 hours. It is not strange that the 

 onions rotted. 



The important role which water plays' in this rot is shown by 

 the behavior of laboratory cultures. Sound onions were cut open, 



2Halsted, B. D. The Root Rot of Salsify. Gard. and Forest. 3: 576. N. 

 1890: Also, Eleventh Ann. Rept. N. J. State Ag. Exp. Sta., 1890: 352. 



3Rept. N. Y. State Weather Bureau, vol. X, No. 7, p. 11, and No. 8, p. 11. 



