316 MAINS AGRICULTURAL EXPERIMENT STATION. K)Oj. 



mix with the air of the room. To avoid injury from the strong 

 gas as it is liberated no potatoes should be placed directly above 

 the generator. 



There is less danger of retarding germination if the disin- 

 fection is performed before the sprouts begin to appear. 



The gas is more effective if the temperature of the room is 

 6c degrees to 65 degrees F. at the beginning of the disinfection 

 period than will be the case with a lower temperature. 



The gas also appears to be more effective in a moist atmos- 

 phere than in a dry one, therefore it is recommended that part 

 of a pailful of boiling water be sprinkled over the floor of the 

 room just before the generator is started. Do not wet the 

 surfaces of the potatoes, for experiments have shown that the 

 gas is more effective on dry potatoes than those which are 

 moistened just before being treated.* 



Can Potato Soil be Limed with Safety? 

 With potato growers clover is usually an important factor 

 in the rotation. Unfortunately clover, like potato scab, thrives 

 best under alkaline soil conditions. To bring about the required 

 alkalinity the practice of liming is resorted to with increasing 

 frequency. The Station has recently secured some remarkably 

 good stands of clover by liming Aroostook potato soils. The 

 question naturally arises, can the amount of lime be so gauged 

 as to produce the required stand of clover and not materially 

 increase the amount of scab when potatoes are again planted 

 on the land? Fortunately one of these trials which was located 

 on the Watson farm at Houlton was made up of a series of 

 alternate acre plots treated with 1000 pounds, 500 pounds and 

 no lime per acre. The lime was applied when stocked with 

 clover in oats in 1905. With a 3-year rotation potatoes would 

 be the crop for 1907, so permission was secured to plow a strip 

 directly across the middle of these plots and at right angles 

 with them. Five long rows of potatoes were planted on this 

 strip. It was intended to use treated seed, but through a mis- 

 understanding on the part of the man in charge of the planting, 

 clean, untreated seed was used instead. The treatment of the 



*Vt. Sta. Rpt. 17, p. 401 (1904). 



