226 



Bulletin 230. 



were read every two hours for a period of twenty-four hours on Satur- 

 day and Saturday night of each week. The air temperature readings 

 covering the same hours each week were taken by the U. S. Weather 

 Bureau with apparatus located about two hundred yards distant 

 from the potato plats. At five o'clock in the afternoon of the days 

 (Saturdays) upon which temperature readings were taken, samples of 

 soil were taken from the whole plat in duplicate at the depth of two, 

 four, six and eight inches for the purpose of determining the moisture 

 content. Inasmuch as the surface of the three plats, as a whole, is 



rolling, the soil samples 

 were taken one on the 

 lower side and one on the 

 upper side each time. 



Level culture was given, 

 and during the growing 

 season the plats were 

 cultivated six times and 

 sprayed with Bordeaux 

 and Paris green five times. 

 When the potatoes were 

 dug, note was made of the 

 depth at which each tuber 

 grew, and later each tuber 

 was weighed and examined 



Fig. ISO.— Longitudinal section from the middle ^^th internally and ex- 

 portion of the same tuber from which Fig. 179 ternally and SCOred upon 

 was taken. The section is of the same thickness a series of points upon 



which the 

 estimated. 

 228.) 



The soil in which the 

 potatoes were planted is of the type known as Dunkirk' gravelly 

 loam. It is a good potato soil, although in this particular 

 area the underlying subsoil, which is not so productive as the 

 surface soil, lies too near the surface to give the roots the 

 feeding area below that they would seem to demand. It was soil 

 adjacent to this plat, and of the same type, which produced yields 

 of potatoes of from 300 to 350 bushels per acre for a series of succes- 

 sive years without the addition of fertilizers or manures. (See 

 Cornell Bulletins.) 



During the growing season, hills of potatoes from each plat were 

 dug in order to study the position of the tubers in relation to the 



and boiled in the same manner. The stem end 

 m,ay be recognized by the cleavage of the sub- 

 stance. There was a small cavity in the bud 

 end. Compare Figs. 179 and 181. 



quality was 

 (See table p. 



