1903.] PUBLIC DOCUMENT — No. 33. 149 



was made with the nearest nothing plots only, the apparent 

 effect is as follows : — 



Pounds. 



Average increase due to application of 150 pounds of nitrate, 446.5 

 Increase due to application of 200 pounds of nitrate, . . 898.0 

 Increase due to application of 250 pounds of nitrate, . . 955.0 



All these increases are more than sufficient to cover the 

 cost of the application of nitrate made. 



XIII. — Variety Test, Potatoes. 



Dm'ing the past year we have grown, under conditions 

 allowing a fair opportunity for comparison, thirty-three 

 varieties of potatoes. The seed of all varieties was the 

 first generation of our own growing. We included for pur- 

 poses of comparison an equal area of one of the standard 

 varieties, — Beauty of Hebron, — with seed of the second 

 generation, from northern Maine. We raise our own seed, 

 because it is recognized that the locality in which seed stock 

 is produced and the way in which it is stored and handled 

 has much to do with its productive capacity. We cultivate 

 all varieties of potatoes that we test, therefore, two years, 

 the first year being the preliminary test, made with small 

 quantities of seed gathered from the many different sources 

 from which a list of varieties must be made up. It is the 

 product of this first crop that we use a second year in a 

 final test, the seed of all varieties being stored and handled 

 in precisely the same way. It is the results of this second 

 year's test which are here reported. 



The seed tubers planted this year were selected to as 

 nearly as possible an average size of 60 grams in weight for 

 each variety. The tubers were treated with corrosive sub- 

 limate in the ordinary way on April 9, and were spread in 

 a light and sunny room in a single layer until May 14, when 

 they were planted, being first cut to pieces of two good eyes 

 each. The pieces were planted 1 foot apart in rows 3 

 feet apart. The field is one which has been used for a num- 

 ber of years in experiments Math corn, in growing which a 

 moderate application of fertilizers alone has been .made. 



