EXPERIMENTS WITH INSECTICIDES AND FUNGICIDES. 203 



seem to indicate a sufficiently increased yield to pay its cost ($5 

 to $7). These results are not confirmed by the Station experi- 

 ments. 



NOTES ON FUNGICIDES. 

 The year 1902 is the first year in which potato blight has been 

 particularly bad since the Station began experiments in the great 

 potato growing section of this State. In 190 1 there was a large 

 acreage with some blight and rot on unsprayed fields. In that 

 season sprayed potatoes, even though treated only once or twice 

 were free from blight and rot. Unfortunately this apparent help 

 from imperfect protection led many to believe that the four to 

 six sprayings urged by the Station were unnecessary and that 

 two sprayings were equally good. In 1902, even in the case in 

 which the spraying has been quite thorough, the results have 

 been disappointing, as the protection has been only partial. For 

 example : In the Experiment Station experiments with insecti- 

 cides there was found on fairly drained ground a loss of 10 per 

 cent due to rot, and on poorly drained ground the loss was much 

 greater. One large grower recently at the Station was much 

 discouraged at the outlook ; he said he sprayed three times and 

 fully half of his potatoes rotted. However, it came out in the 

 course of the conversation that a piece which he sprayed twice 

 rotted so badly that he did not dig them. Thus the extra spray- 

 ing gave him one-half of a crop and it is probable that if he 

 had sprayed twice more his loss from rot would have been no 

 greater than in the Station experiments. The blight progressed 

 peculiarly the present season. For the most part potatoes were 

 late planted and through July and August made very rapid 

 growth, much of the time an inch a day. This soft, succulent 

 foliage was apparently peculiarly susceptible to the blight. 

 Blight, however, did not appear until late, so that in most 

 instances the tops were covering the ground and forming a dense 

 mat at the time in which it appeared and most pieces had not 

 been sprayed for some little time previous for fear of injuring 

 the tops by driving through the field. The blight progressed 

 somewhat slowly but still made decided progress at lower tem- 

 peratures than has usually been supposed to be favorable to its 

 growth. While pieces quite thoroughly treated have not been 

 perfectly free from rot, the season has added to the importance 



