3IO REPORT OF THE COMMISSIONERS OF 



Trees should not be tapped until they are thirty years old, at which time they will 

 be over fourteen inches in diameter if grown under favorable circumstances. Sugar 

 can be made from small, young trees, but they yield less sap and are not so able to 

 withstand any injury which might arise from the boring. The richest sap is found 

 nearest the bark, the shallow borings furnishing the whitest sugar. The deeper the 

 bore the smaller percentage of saccharine material and the darker the sugar. Care 

 should be taken in boring to select a spot where the bark is clean and healthy, and 

 to avoid any place where there is the least sign of rot ; for any decay in the wood will 

 discolor the sap. One bucket of discolored sap will injure or spoil several barrels of 

 the pure liquid. 



The question naturally arises here, one that is often asked, whether this annual 

 tapping for a long term of years does not injure or eventually kill the tree. In reply 

 it may be safely asserted that the present system of tapping, making only one or two 

 shallow holes each year, does no perceptible harm. Of course, it does not benefit the 

 tree, and, to some slight extent, may injure it. But the number of years during which 

 the trees withstand the boring without showing any sign of failure or deterioration, so 

 far exceeds the time in which a large maple can be grown from seed, that any 

 discussion on this point is needless. 



In I 791, Dr. Benjamin Rush, of the University of Pennsylvania, wrote a letter to 

 Thomas Jefferson, who was then vice-president of the American Philosophical Society, 

 in which the writer discussed at considerable length the manufacture of maple sugar. 

 He mentions a tree which not only survived, but flourished, after being tapped 

 annually for forty-two successive years. In view of the large incisions used then his 

 statement is worth noting. He attributes the ability of the species to withstand the 

 loss of sap to the fact that the sap is diffused through all parts of the tree, a peculiarity 

 in which it differs materially from most of our native trees. Owing to this peculiarity 

 a hard maple has been known to live three years after it had been "girdled" by an 

 axe for the purpose of killing it. Dr. Franklin B. Hough * mentions a sugar bush 

 which he knew had been tapped annually for seventy years, and was still in good 

 condition. Some of the trees had grown old and died, but as they were replaced by 

 younger ones the grove remained with its productive capacity unimpaired. Professor 

 Charles S. Sargent f states that there are trees in Northern New York " which are 

 known to have yielded sugar every year for a century, and which, while much swollen 

 about the base from repeated wounds, are still vigorous and fruitful." If these trees 

 had been tapped from the beginning in accordance with present methods, it is fair to 

 assume that they would have retained their symmetry as well as their vigor. 



* U. S. Department of Agriculture ; Report on Forestry ; Washington, 1884. 

 f Silva of North America. Vol. II, p. 99. 



