SIZE OF POTATO SETS. 
tubers of the same weight. In the first set of experiments the 
largest yield was obtained from whole tubers weighing from 10 to 
12 ounces, with the 8 to 10 ounce tubers second. The others came 
in the following order: 6 to 8, 4 to 6, 3 to 4 and 12 to 14 tied, 2 to 3, 
and 1 to 2. The net value of the crop, deducting the cost of seed 
used, gives an entirely different aspect to the experiment. The 1 
to 2 ounce whole seed showed a net value of $42.95 per acre; the 2 
to 3 ounce, $42.90; the 3 to 4 ounce, $38.90; and the 4 to 6 ounce, 
$35.45. The 8 to 10 ounce seed came next with $28.50, closely 
followed by the 6 to 8 ounce with $28.20, while the 10 to 12 ounce 
seed gave the largest yield but showed a profit of only $17.25 per 
acre. The 12 to 14 ounce seed gave the least profit, $10.40 per acre. 
Brunk's conclusions (19) from a study of the relative merits of 
10-ounce whole tubers, egg-size whole tubers, 2 to 4 eye sets from 
medium-sized tubers, and 1-eye sets for seed purposes are summarized 
in the following five sentences: 
(1) The greater the quantity of the seed planted the greater the crop in total 
product. 
(2) Generally, the more seed the more good potatoes of merchantable size. 
(3) The most profitable seed potatoes on the average are those of egg size. 
(4) The less quantity of seed used and the more it is cut, the less the proba- 
bility of getting a full stand. 
(5) Cutting potatoes to a single eye increases the missing hills so much as to 
materially reduce the crop. 
It is believed that Brunk's second conclusion may well be chal- 
lenged, as it is invariably true under normal conditions of growth 
that as the size of the set increases above the average or normal-sized 
set the percentage of merchantable-sized tubers decreases. 
Taft (95, p. 18) found that halved tubers gave a larger yield of 
merchantable tubers than whole tubers, and the net increase was 
also greater. In one set of data whole tubers gave a net increase 
over seed used of 251.3 bushels per acre, while tubers of the same 
size halved gave a net increase of 296.7 bushels; quartered tubers, 
244.1 bushels; eighths, 215.3 bushels; and single eyes, 173.9 bushels. 
In another experiment where whole and halved tubers of different 
sizes were compared Taft obtained the results shown in Table 2. 
Table 2. — Comparative test of whole and halved potato tubers and single-eye sets 
reported by Taft in 1890. 
Average 
weight 
(ounces) . 
Yield (bushels). 
Kind of seed. 
Mer- 
chant- 
able. 
Small. 
Net 
increase. 
4$ 
if 
8 
370 
361 
433 
349 
305£ 
173£ 
62* 
31* 
31 
45 
44 
21§ 
372£ 
Do 
348f 
442 
372 
338 
These data show that the largest }ueld was obtained from a 3J- 
ounce tuber halved. It is also shown that the net increase from 
whole tubers weighing 4| ounces was practically identical with that 
from If -ounce whole tubers. No explanation is given in regard to 
the poor showing made by the single-eye sets. 
