Family Solanaceae 337 



of space in the disinfecting room. With less quan- 

 tities of potatoes in this space, the formaldehyde 

 gas will injure the germination and produce a pitting 

 on the tuber. A tight room is used for this pturpose, 

 and the seed potatoes are placed in open crates, or in 

 layers in slated bins, or in small piles on the floor. 

 For each pne thousand cubic feet of space, three 

 pints of formaldehyde (40%) pure and twenty- three 

 ounces of potassium permanganate shotild be used. 

 The latter is placed in deep wooden or earthen dishes, 

 and the formaldehyde is poured on the salt crystals, 

 the disinfector rushing out locking the door at once. 

 The ftunigated house is kept closed for twenty-four 

 hours. 



Spraying. The field diseases such as early and late 

 blight, tip bum, and, in fact, all other foliage diseases 

 except leaf roll and curly dwarf may be controlled by 

 spraying. Lime svdphur in any form has failed to 

 give satisfactory results. The spray recommended 

 is 5-5-50 Bqrdeaux mixture. To each one hundred 

 gallons of Bordeaux, add one pound of Paris green 

 or six pounds of lead arsenate paste. Spraying 

 should begin when the plants are about six inches 

 high, and from 3 to 6 applications should be given, 

 depending on the climatic conditions. To yield the 

 desired result, sprajringmust be appUed in a thorough 

 manner. It is a good form of insurance, as has been 

 demonstrated by many workers. Table 16 by Lut- 

 man' clearly shows the profits to be derived from 

 spraying. 



I Lutman, B. F.,Vennont Agr. Expt. Sta. Bui. 159,: 216, 296, 1911. 



