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. — Relati-o-n 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.] 



Variety. 



Year. 



Weight 

 at the 

 begin- 

 ning. 



Dooley 19X2-13 



Nancy Hail 1912-13 



Doolev 1913-14 



Do 1913-14 



Nanny Hall 1913-14 



1914-15 



Ilall 1915-16 



Total.... 

 Average. 



Sorted. 



Lbs. 



300 

 50 



KIT 

 42 

 42 

 36 

 32 



1, 349 



Time 



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. 



Per 

 cent. 

 9.2 

 22.0 

 10.3 

 13.7 

 17.7 

 11.1 

 9.2 



10. 82 



Loss 

 due to 

 decay. 



Weight Time 

 at the 



Per 



cent. 

 0.93 

 6.00 

 2.70 

 5.00 

 4.40 

 8.00 



Not sorted. 



nuig. 



Lbs. 



300 



50 



2,527 

 42 

 42 

 36 

 29 



3,026 



Days. 

 125 

 182 

 I or, 

 131 

 125 

 152 

 103 



132 



Weight 

 at end of 

 storage 

 period. 



Lbs. 

 272. 79 

 40.00 

 2, 239. 93 

 38.26 

 36.67 

 32.11 

 20. 74 



2, 680. 50 



Shrink- 



Per 

 cent. 



9.30 

 20.00 

 11.36 



8.90 

 12.70 

 10.80 



7.80 



Loss 

 due to 



Per 



cent. 

 0.74 

 4.00 

 1.20 

 2.00 

 1.11 

 2.00 



Except in one experiment with the Nancy Hall variety, the decay 



reater in the sorted lots than in those not sorted. The average 



of the sorted lots was 2.63 per cent and of those unsorted 1.21 



per cent. Under less careful handling there would probably have 



been more decay in both soiled and unsorted lots, but especially in 



the former. No definite explanation can be given for the largeaj 



percentage of decay in sweet, potatoes that were sorted, but it is 



!e thiii slight bruising resulted from handling, and thai the 



sorting increasec the chance of spreading disease from decayed to 



37029°— 22- 2 



