TECHNIQUE OF TAPPING 199 



French and American Methods Contrasted. — The main difference 

 between tapping methods in France and the United States on National 

 Forests seems to be in the width of the face and the annual rate of in- 

 crease in its height, and the number of faces per tree. In the United 

 States the first streak cannot begin higher than 10 inches above the 

 ground. In France it can be anywhere above the root swelling. In 

 the United States the maximum depth of streak is 0.5 inch; in France 

 it is approximately 0.4 inch. In the United States in Federal tapping 

 operations ^^ no tree less than 10 inches can be tapped, and trees 16 

 inches and over can have two faces, while trees 10 to 16 inches can 

 have but one face. In France the minimum diameter of trees tapped 

 alive on State forests (trees to be removed in thinnings can be tapped 

 to death no matter how small) is 13 inches and the number of faces is 

 specially designated by the local forest officer. In the United States the 

 face can be 12 to 14 inches wide with no specified decrease in width as 

 the face proceeds up the tree. In France it is 3.5 to 2.4 inches, decreasing 

 each year as the distance above the ground increases. The maximum 

 height increase per year in the United States is 16 inches, while in France 

 the face can be lengthened 24 to 26 inches, and even up to 39 inches 

 in case of 4-year tappings. Without exhaustive experiments the best 

 methods to follow cannot be stated, but tentative results from the Florida 

 Forest in the United States show the French method is not applicable 

 to mature, large timber and that the yield in resin per square inch of face 

 is slightly greater with the American (Government) method of wide faces. 



Technique of Tapping. — The trees (on State forests) for tapping alive 

 are blazed on the bark and stamped " AF " at the base and at breast height. 



It is necessary ^^ for a good worker to be able to cut a thin, even slice 

 of wood to increase face and to continue the face vertically following the 

 grain of the wood. The sHver is about 3 inches wide, 5 to 7 inches long, 

 and usually less than 0.4 inch deep. The first step is always to smooth 

 the outer bark with the axe. The tendency is to bark too large rather 

 than too small an area. In placing the gutters care should be taken 

 not to cut into the tree with the place-crampon more than 0.2 inch; this 

 is a sufficient depth, inasmuch as the gutter is glued by the sap as soon as 

 it flows, and besides if the gutters are set too deep it is very difficult to 

 remove them in the autumn. The gutter should, of course, be sHghtly 

 inclined toward the ground so that the sap will run off into the cup. 

 has not yet been invented. It must be easy to place, secure, easy to remove, and must 

 not damage the tree. 



Ricard states that the yield of resin is greatest near the ocean, with thrifty, rapidly 

 growing trees, with thin chipping at frequent intervals, and with hot weather. 



-'' It would be unwise to attempt to pass legislation limiting the size of trees that 

 should be tapped. This is a technical problem to be solved for each forest. 



28 Le Pin Maritime (Manuel Pratique) par R. Cattin et J. J. Saint-Jours. 



