SWEET-POTATO STORAGE STUDIES. 9 
careful handling. The conditions under which this experiment was 
conducted were more favorable than would ordinarily exist in com- 
mercial practice. The loss due to decay was not as great as would 
usually occur. Under ordinary conditions the cut and bruised sweet 
potatoes should be disposed of at harvest time. 
COMPARISON OF THE PRACTICES OF SORTING AND NOT SORT- 
ING STORED SWEET POTATOES. 
It has been very generally believed that when sweet potatoes be- 
gin to decay in storage they should be sorted to pick out the diseased 
ones. Observations on this point indicated that this sorting was of 
doubtful value. Experiments were begun in 1912 and continued in 
each of four years to determine whether it is safe to pick out the 
diseased sweet potatoes. The sorting was carefully done, so as to 
avoid bruising as much as possible, about once a month during the 
storage period. 
In all. seven tests, including three varieties, were made. The aver- 
age storage period for all of these experiments covered 134 days. 
The results are given in Table 4. 
Table 4. — Relation of sorting to the keeping quality of sweet potatoes. 
[Shrinkage and decay averages for three varieties in seven storage-house tests in Southern States during 
four seasons.! 
Varietv. 
Year. 
Dooley 1912-13 
Nancy Hall 1912-13 
Dooley 1913-14 
Do j 1913-14 
Nancy Hall ' 1913-14 
Big-Stem Jersey.., 1914-15 
Nancy Hall 1 1915-16 
Total 
Average. 
Sorted. 
Weight 
at the 
begin- 
ning. 
Lbs. 
300 
50 
847 
42 
42 
36 
32 
1,349 
Time 
in 
stor- 
Days. 
125 
182 
106 
131 
125 
152 
103 
132 
Weight 
at end of 
storage 
period. 
Lbs. 
272. 4 
39.0 
759. 76 
36. 25 
34.57 
32.00 
29.06 
1, 203. 04 
Shrink- 
age 
Pa- 
cent. 
9.2 
22.0 
10.3 
13.7 
17.7 
11.1 
9.2 
10.82 
Loss 
due to 
decay. 
Pa- 
cent. 
0.93 
6.00 
2.70 
5.00 
4.40 
8.00 
2.63 
Not sorted. 
Weight Time 
at the | in 
begin- stor- 
ning. age. 
Lbs. 
300 
50 
2,527 
42 
42 
36 
29 
Days. 
125 
182 
106 
131 
125 
152 
103 
182 
Weight 
at end of 
storage 
period. 
£6*. 
272. 79 
40.00 
2, 239. 93 
38.26 
36.67 
32.11 
26.74 
3.50 
Shrink- 
age. 
Pa- 
cent. 
9.30 
20.00 
11.36 
8.90 
12.70 
10.80 
7.80 
Loss 
due to 
decay. 
Per 
cent. 
0.74 
4.00 
1.20 
2.00 
1.11 
2.00 
1.21 
L 
Except in one experiment with the Nancy Hall variety, the decay 
was greater in the sorted lots than in those not sorted. The average 
decay of the sorted lots was 2.63 per cent and of those unsortecl 1.21 
per cent. Under less careful handling there would probably have 
been more decay in both sorted and unsorted lots, but especially in 
the former. No definite explanation can be given for the larger 
percentage of decay in sweet potatoes that were sorted, but it is 
possible that slight bruising resulted from handling, and that the 
sorting increases the chance of spreading disease from decayed to 
87029°— 22 2 
