PROCEEDINGS OP THE SUMMER MEETING. 61 



luscious St. Joseph peaches, which are now known only in history. The 

 climate is the same today as it was then. If we can restore to the soil the 

 elements it possessed then, what is to hinder our producing anew those 

 peaches'? 



TREATMENT FOR POTATO SCAB. 



Mr. L. J. Post of Lowell appended the following to his report: 



I treated quite a quantity of potato with solution of corrosive sublimate, 

 1 to 1000, for scab. I took two oz. of sublimate and dissolved in two gal- 

 lons of warm rainwater, in a wooden pail, stirring it frequently; then poured 

 this into thirteen gallons more of water, in half of a kerosene barrel. We 

 used three baskets, each holding one and one half bushels, filled about level 

 full, of potatoes. Set one of these baskets into the solution, and it will fill 

 the half barrel full, and also cover the potatoes. Let them remain a few 

 minutes, to become thoroughly wet. Then raise them slowly and set in a 

 common kerosene barrel with one head out. It will probably just set in 

 without dropping down. Leave it here a short time to drain. The water 

 can be poured back into the half barrel frequently. In using three baskets 

 we fill one, have one in the solution, and one draining. If a good many 

 are to be dipped, keep a second supply of the solution close by, to replen- 

 ish the one half barrel as the solution is taken out by the potatoes. If the 

 baskets are made as they are in this vicinity, the water will pass through 

 very readily. There is no danger in handling this solution, even if there 

 are sores on the hands, as it is the same solution used in surgery. Of course 

 it would not be just the proper thing to drink. 



TO PREVENT POTATO SCAB. 



In continuance of this subject, the secretary read the following paper 

 prepared by Mr. R. J. Coryell, one of Prof. Taft's assistants at the 

 Agricultural College: 



Potato scab is familiar to all potato-growers. It is prevalent wherever 

 the potato is grown, and its origin is probably in the remote past. The 

 cause of scab was not known until within the past two years. Even yet 

 the exact life-history of the organism that causes it has not been fully 

 traced out. The theories that it was caused by angleworms, wireworms, 

 manure, or by the condition of the soil, are disproven, and the fact estab- 

 lished that it is caused by a plant organism resembling both the fungi and 

 bacteria. 



It propagates by spores which are brought into contact with the growing 

 potato and enter it at a lentical or breathing pore, and begin their work of 

 destruction. Its presence is first shown by a tiny crimson spot. This col- 

 oration soon enlarges. The potato, in its effort to heal the wound, makes 

 an increased growth of cells under the diseased portion, and tends to throw 

 it off, which accounts for the raised surface of the scab as seen in some 

 specimens. The disease attacking the potato earlier in its growth, and 

 consequently having a longer time for its action, may involve the underly- 

 ing tissues to a greater extent and cause the formation of cavities, which 

 are filled more or less with the decaying mass of destroyed tissues. Worms, 

 mites, myriapods, etc., feeding on this decayed substance, led many to think 

 that they were the cause of the injury. 



