46 



As the varieties presented in the table are arranged in the order of 

 the percentage of rotten tubers, starting with the smallest and finishing 

 with the greatest percentage of rot, the results regarding the percent- 

 age of disease are shown quite clearly. It will be seen that the Holborn 

 Abundance, Robertson's Champion, Skerries, Up-to-date, and Stray 

 Beauty varieties each had less than five per cent, of rot in comparison 

 with the Beauty of Hebron, Weld's Orange, and Montana Bluff, each 

 of which had upwards of fifty-five per cent, of rot. 



It is claimed by some that early potatoes, and by others that late 

 potatoes, a'-e the freest from the attacks of this disease. According 

 to the reports of the last two years, the average results of ten early, ten 

 medium, and ten late varieties of potatoes are as follows : 



ClasseB According to Maturity. 



Ten early varieties . . . 

 Ten medium varieties 

 Ten late varieties 



Number of days in 

 reaching maturity. 



Percentage of rotten 

 potatoes. 



25.8 

 33.8 

 10.9 



From these results, it appears that of all the varieties grown in the 

 Experimental Department in each of the past two years, the late varie- 

 ties, as a whole, were the freest from rot. 



Those varieties which had the largest percentage of rot did not 

 yield as many sound potatoes as the varieties having the least percent- 

 age of rot, as will be seen by the following figures : 



Amotint of Kot. 



Twelve varieties having the least rot 



Twelve varieties having the most rot .... 



Bushels of sound 

 potatoes per acre. 



219.2 

 129.9 



Percentage of rotten 

 potatoes. 



5.2 

 52.9 



This eives us some idea of the great loss caused bv means of the 

 rot on the potato crop of the past two years. The November Crop Bul- 

 letin for 1904 had the following regarding the condition of the potato 

 crop : "The extent of the loss from rot is variously estimated at from 

 tw.r-ty to fifty per cent." This will show the importanrp of planting 

 those varieties which produce large yields of potatoes of good quality 

 and which are less subject to rot than other varieties. 



In averaging the yields per acre produced by each of forty-six 

 varieties of potatoes grown in the experimental grounds for the past 

 five years in succession, the — -''atest number of bushels of sound pota- 

 toes were produced by the fnllnwin? : Empire State, 269; Seedling 

 No. 230, 256; Dempsey's Seedling, 252; Pearl of Savoy, 251; White 

 Elephant, 251; American Wonder, 247; Holborn Abundance, 247; The 

 Daisy, 243; Rural New Yorker No. 2, 243; and Rural Blush, 240. 



