328 STATE POMOLOGICAL SOCIETY. 



species thus tapped, and all others named in this paper, will be mentioned by 

 their common English names, which are familiar to most persons ; but in order 

 that these may be clearly understood, a list is appended containing both the 

 English and the Latin names. The following were tested, as above described, 

 for sap, viz.: Hemlock, black spruce, balsam fir, alder, European alder, striped 

 maple, red maple, sugar maple, shad-bush, white birch, black birch, yellow 

 birch, paper birch, hornbeam, chestnut, hickory, bitternut, cornel, thorn, 

 -quince, ash, beech, butternut, black walnut, mulberry, ironwood, white pine, 

 yellow pine, buttonwood, aspen, English cherry, black cherry, mountain ash, 

 apple, pear, peach, white oak, red oak, glaucous willow, white willow, bass, 

 linden, elm, and grape. These trees were visited every day about noon for 

 several Aveeks, the holes being renewed as often as necessary, and whenever 

 they were found flowing the number of drops per minute was recorded, except 

 in the case of such trees as flowed somewhat abundantly and for a considerable 

 time. The whole amount of sap from those of the latter class w^as carefully 

 collected and weighed daily. It will be seen that the sugar maple flows at 

 any time when stripped of its foliage, provided the weather is favorable, the 

 principal condition being a temperature above freezing, directly after severe 

 frost. A comparison of the flow from this species with the pressure on the 

 mercurial gauges, and with the temperature as indicated in the meteorological 

 observations, kindly furnished by Prof. E. S. Snell, LL. D., of Amherst College, 

 will convince the inquirer that there is an intimate connection between these 

 three sets of facts. 



THE QUANTITY OF SAP 



from a sugar maple during the season is much greater than from any other 

 tree flowing from the same causes. Thus the entire flow from the butternut 

 was less than the product of the sugar maple for a single day. The ironwood 

 and the birches, however, surpass even the maple, both in the rapidity and 

 amount of their flowing, if Ave make allowance for the diff'erence in the size of 

 the trees tested. A paper birch, fifteen inches in diameter, flowed in less than 

 two months one thousand four hundred and eighty-six pounds of sap; the 

 maximum flow, on the fifth of May, amounting to sixty-three pounds and 

 four ounces, Avhich is probably three times the average yield of a sugar maple 

 of the same size. These latter species will not bleed during the winter, and 

 seem to do so in the spring from a cause entirely different from that which 

 afiects the trees which bleed in fall and winter. The grape, which is often 

 thought to bleed more freely than any other species, though later in the sea- 

 son, really floAvs but little, the total amount from a very large vine beingeleven 

 pounds and nine ounces. 



Among the species subjected to trial, only those mentioned as bleeding ex- 

 hibited this phenomenon. The folloAving flowed for a short time, or very irreg- 

 ularly, or very slowly. The shad-bush Avas seen to flow, on the eighth of April, 

 one drop in fifty seconds. The hickory bled one drop per minute of very sweet 

 sap, on the fifteenth of April, and the cornel, ten drops on the same day. The 

 European alder flowed three drops per minute, April ninth, and the common 

 alder, four drops, on the twenty-first of March, and on the tenth of April, nine 

 drops from one spout and six drops from another, inserted six inches belowthe 

 former. The black walnut yielded a small amount of sap during several weeks, 

 and, March thirtieth, bled six drops per minute. The buttonwood flowed forty 

 drops per minute, March twenty-fifth, and one hundred on a very cold day, 

 the eighth of April. The total amount, however, was very small. The apple 



