62 



This Jias been I'lilly described in Farmer's J>nlieLin No. 4()7, of 

 the United States Department of Agriculture, and need not be 

 considered in its entirety here. 



For this worlv the most essential implements are a gouge, a 

 mallet or hammer, a pot of tar or paint, and a brush to apply the 

 latter; also a whetstone for keeping the gouge sharp. When a 

 diseased spot in the bark is located, it is carefully cut out with 

 the gouge and mallet, care being taken to cut the bark perhaps 

 (»ne-half inch beyond the discolored area which is usually so 

 prominent a characteristic of diseased bark. It is extremely im- 

 portant that the gouge be kept scrupulously sharp. If it is dull, 

 the pressure required in forcing it through the bark will invari- 

 ably result in some injur}^ to the delicate cambium cells at the 

 edge of the cut. This means that the new growth will start 

 back under the bark some distance, an eighth, a quarter, a 

 half inch, or even more, and not close to the edge of the cut, 

 where it should start under the most favorable conditions. 



During the growing season the new groAvth begins to lift the 

 old bark within a week or ten days. If this growth does not be- 

 gin close to the edge of the cut, we shall find in the course of 

 three weeks, under the uplifted edge of the bark, the finest kind 

 of a shelter for all kinds of small grubs, beetles, etc. ; all of which 

 are Avell known danger factors in connection with the si)read 

 of the disease. 



At most seasons of the year, it is highly important that the 

 edge of the cut along tlie caml)ium line be covered with paint or 

 tar as promptly as possible. This is an important, and often 

 essential, point in coaxing the new growth to start closer to 

 the edge of the cut than i' ('\i'" would under perfectly normal 

 conditions. By using a sharp gouge and promptlj^ covering the 

 cut edges, we have many times had the satisfaction of seeing 

 the new growth start within a thirty-second of an inch of the 

 edge of the cut, and be readily visible to the unaided eye in less 

 than a week. Anything better than this can scarcely be expected. 

 Of course, all portions of the cuts must be finally, carefully and 

 completely painted with tar, paint, or other suitable waterproof 

 coating, and it is, theoretically at least, a good plan to paint the 

 cut surface with copper sulphate or Bordeaux before waterproof 

 coating is applied. 



