A Dry Rot of the Irish Potato Tuber 
83 
3. Lime and sulfur. The tubers were dusted over with a powder 
composed of three parts of air-slaked lime and one part of 
the flowers of sulfur. 
4. Lime-sulfur wash. This was made by boiling in the usual 
manner five pounds of sulfur, five pounds of lime, and fifteen 
gallons of water. After treatment the potatoes were dried 
before being placed in the storage bin. 
5. Formic aldehyde solution. The tubers were placed in sacks 
and dipped for two hours in a solution of one pint of 40 per 
cent formic aldehyde solution (often called "formalin") in 
a barrel of water. The tubers were then dried before being 
placed in storage. 
6. Formic aldehyde vapor. The tubers were exposed to the 
vapors generated by twenty-three ounces of potassium per- 
manganate placed in three pints of a 40 per cent solution of 
formic aldehyde (formalin) to each one thousand cubic feet 
of space. 
7 Check. These tubers were not treated at all. 
8. Check. These tubers were wounded by walking over them 
before they were placed in storage. 
The tubers were placed in bins two feet wide and five feet 
long and were about three feet deep in each of these bins. The 
bins had previously been thoroly disinfected with formic aldehyde 
solution. Treatment was applied and the potatoes were stored 
October 1 and the counts were made the following April 25 The 
results are shown in Table 26. 
In the first eight lots the World's Fair potato was employed, 
while for two of the checks smaller lots of the Blue Victor and 
the Early Ohio were employed. 
Table 20. — Results of experiments in the control of dry rot. 
Treatment 
Total number 
of tubers 
Number 
rotted 
Per cent 
rotted 
1108 
133 
12.00 
1393 
227 
16.08 
3. Lime and flowers of sulfur 
1208 
291 
24.08 
1420 
45 
3.16 
5. Formalin dip 
1221 
60 
4.09 
6. Formalin vapor 
1459 
67 
4.59 
7. Check— not bruised 
1121 
182 
16.23 
1262 
397 
31.46 
9. Check -Early Ohio 
1000 
316 
31.60 
10. Check— Blue Victor 
641 
67 
10.45 
This experiment has clearly demonstrated that dry rot during 
storage may be held in check thru treatment of the tubers before 
