1216 EARLE V. HARDENBURG 



equidistant spacing of 38 inches for each type of seed, more per acre of 

 the large than of the small type was planted. Aicher (1917) compared 

 the yields from three lots of whole seed of a given variety having an average 

 tuber weight of 8, 4, and 3 ounces, respectively. Tho Aicher did not state 

 the amount of seed per acre used for each lot planted, the sets of each lot 

 were planted 16 inches apart in rows 3 feet apart. Aicher reported that 

 as the size of the whole seed was increased, the number of stalks per hill 

 and the total yield per acre were increased. There was little difference 

 in the percentage of marketable yield between the three lots. It must be 

 concluded from this that large whole seed is better than small whole seed, 

 under equidistance of planting, only because of the greater weight of seed 

 used. Welch (1917), in a similar experiment and under similar conditions, 

 duplicated Aicher's results almost exactly, except that he obtained a 

 decrease in the percentage of marketable yield as the size of the whole 

 seed increased. It is clear that the greater yields obtained by Welch 

 from the larger whole seed were due primarily to the almost doubled amount 

 of seed involved in each increase in size of seed used. Harwood and Holden 

 (1893) have brought together the results obtained at the New York, 

 Maryland, Tennessee, Kentucky, Louisiana, Wisconsin, and Utah stations, 

 in all of which it was shown that in many cases not only the gross but also 

 the net yield was greatest from the largest whole seed tubers. However, 

 in all cases this increased yield was obtained from the greatly increased 

 amount of seed used. Zavitz (1916) selected continuously, for eleven 

 years, seed of small unmarketable, small marketable, medium marketable, 

 and large marketable, whole seed tubers, and planted each lot in duplicate 

 plots. With but one slight exception in the eleven years, his average 

 marketable yield from the four types of seed showed an increase with each 

 increase in size of seed used. The average yields per acre from the 

 smallest to the largest seed, for the eleven years, were 105, 145, 181, and 

 203 bushels, respectively. Zavitz credits these differences in yield to the 

 difference in the weight of the seed tubers, that is, to the difference in the 

 amount of seed planted per acre. Plumb (1890) planted whole seed of 

 Early Rose varying in tuber weight from 14 ounces down to 1 ounce, and 

 concluded from his results that the larger the seed tuber, the greater was 

 the total yield, the earlier the bloom, the taller the plant, and the later the 

 maturity. Plumb obtained a consistent decrease in net yield, however, as 

 the size of the seed tuber increased. He failed to duplicate his test plots. 



Whole as compared with cut seed 



The advisability of cutting seed potatoes depends on three factors: 

 the cost of labor, the cost of seed, and the relative merit of whole as com- 

 pared with cut seed in the effect on yield. Literature reporting experi- 

 mental data on this question considers only the last-named factor. Gutting 

 seed tubers at once facilitates loss of sap by bleeding, and the entrance of 



