SIZE OF POTATO SETS. 
19 
3-ounce halved-tuber lot. The 6-ounce halved and the 3-ounce quar- 
tered tubers came next. The 5-ounce whole tubers were fifth, while 
the 4-ounce halved and 3-ounce whole tubers tied for sixth place. In 
1917 the 5-ounce halved tubers again gave the largest net yield. The 
4-ounce halved seed was a close competitor, with 4-ounce whole, 
2-ounce whole, and 5-ounce quartered tubers occupying third, fourth, 
and fifth positions, respectively. The differences in yield from the 
sizes mentioned are relatively slight and have no real significance. 
In 1918, 5-ounce halved and 5-ounce quartered tubers gave the largest 
net yields, followed by 4-ounce halved, 3-ounce quartered, and 3- 
ounce halved tubers. In the 1919 experiments 3-ounce halved, 3- 
ounce quartered, 4-ounce quartered, and 4-ounce halved tubers were 
very close competitors. It is apparent from these data that there is 
no consistent superiority of any size of seed tuber or set, except pos- 
sibly in the case of 4-ounce and 5-ounce halved tuber sets. In the 1914 
to 1918 average production columns, the 4-ounce halved tubers show 
zoo 
300 
6- 
3- " 
&0£/A/C£r Qi//?£:T£/?£0 
i 
mm 
i 
_J 
1 
\ :■■■:■ 
] 
vaawmmmu 
i 
1 
i 
1 
£?T&Ly<ZV/9770/V 
$gggm&e//t/£rs 
Fig. 1.— Average vields in bushels per acre from Irish Cobbler potato sets of different weights at the 
Virginia Truck Experiment Station, Norfolk, Va., in 1916, 1917, and 1918. 
the highest net yield of primes, while the 3 and 6 ounce halved sets 
are close competitors for second place. The averages for the years 
1915 to 1918 show that the 4-ounce halved tubers produced the 
largest net yield of merchantable stock. The 3-ounce halved tubers 
came next, and 6-ounce halved tubers came third. In the 1916 to 
1918 averages 5-ounce whole, halved, and quartered sets appear for 
the first time. The 5-ounce halved seed gave the highest net yield 
of primes, followed in their order by the 3-ounce halved, the 4-ounce 
halved, and the 5-ounce quartered sets. (Fig. 1.) 
STUDIES AT CARIBOU AND PRESQUE ISLE, ME. 
SIZE OF IRISH COBBLER SEED. 
The experimental studies of the size of set of the Irish Cobbler 
variety conducted at Caribou, Me., in 1914 and on the Aroostook 
Farm, Presque Isle, Me., in 1915 to 1918, the data from which are 
presented in Table 8, were designed to serve as a check on the Nor- 
folk studies. In 1914 the 4-ounce halved tubers gave the highest net 
