EXPERIMENT STATION BULLETINS. 327 



When large quantities of potatoes are to be treated, 

 formaldehyde gas may be used to advantage as fol- 

 lows: * "Place seed tubers in bushel crates or shal- 

 low slat-work bins in a tight room. For each 1,000 

 cu. ft. of air space in the room, spread 23 ounces of 

 potassium permanganate evenly over the bottom of 

 a large, flaring pan or pail placed in the middle of 

 the room. Pour over this three pints of formalin. 

 Close room at once and do not open for 24 or 48 

 hours." 



For blight and Begin spraying with Bordeaux mixture and poison 



"bugs." when the "bugs" first appear, or when the plants 



are about 8 inches high, and repeat about every 2 

 weeks as long as the plants are growing. Spray 

 often in warm, muggy weather; it is not as neces- 

 sary in dry weather. 



Use Bordeaux mixture (6 pounds copper sulphate 

 and 4 or 5 pounds of lime to 50 gallons of water, 

 and put in the poison, about y^ pound of Paris green 

 or 2 pounds of arsenate of lead, or 1 quart of the 

 stock solution of Kedzie mixture. 



PREPARATIONS OF SPRAY MIXTURES. 



FUNGICIDES. 



DILUTE BOILED LIME SULPHUR SOLUTIONS FOR SUMMICR. 



SPRAYING OF APPLES. 



During the past seasons, tests have been made to determine the com- 

 parative value of dilute solutions of boiled lime-sulfur and Bordeaux 

 mixtures for spraying apple orchards. 



The advantages of the dilute lime-sulphur solutions over bordeaux 

 mixture were found to be : 



(a) That the fruit was not russetted as badly. This was especially 

 so with Wagener, R. L Greening, Baldwin, Ben Davis and Hubbardston. 



(b) Ease with which the solution was prepared— where a commercial 

 concentrated brand was used. 



(c) Very slight wear on the pump and packing and no trouble with 

 nozzle clogging, since the Siolution did not contain any grit, as Bordeaux 

 mixture does. 



(d) Appeared to lessen the number of San Jose scales. 



Encouraging as the results have been from the use of the diluted lime- 

 sulphur solution, it must be remembered that it has not been compared 

 with Bordeaux mixture in Michigan in a season when the apple scab fun- 

 gus has been serious, and until this has been done, its use must be consid- 

 ered in the experimental stage and Bordeaux not entirely abandoned. 



The diluted lime-sulphur solution can be prepared for use in several 

 ways. 



1st. Commercial concentrated lime-sulphur solution can be diluted 



*From Bui. 149, Maine Exp. Sta. 



