494 WOODY PLANTS OF MASSACHUSETTS. 
formed Mr. Colman, the agricultural commissioner, that in one 
season he obtained, from one tree, 175 gallons of sap, which, if 
of average strength, would have made 43 pounds of sugar. 
There are different opinions as to the character of the winters 
most favorable to the production of sugar. Open winters are 
thought to cause the sap to be sweetest; and much freezing and 
thawing to make it most abundant and of the best quality. 
Michaux’s inquiries led him to think a cold and dry winter 
most favorable. It is probable that the product depends much 
more on the character of the previous summer. A summer of 
plentiful rain and sunshine, that is, one which furnishes the 
trees with abundant nutriment and is at the same time favor- 
able to the elaboration of the saccharine matter and its deposi- 
tion in the vessels of the wood of the tree, ought naturally to 
prepare a plentiful harvest of sugar for the subsequent spring. 
The time at which the sap begins to run freely varies with 
the season and with the exposure and elevation of the ground. 
In warm and low situations, it is earlier, in cold and elevated 
ones, later. It sometimes begins about the middle of February, 
usually about the second week in March and continues into 
April. A clear, bright day with a westerly wind, succeeding a 
frosty night, is most favorable to the flow of sap; a thawing 
night is thought to prevent its flow; and it ceases during a south 
wind, and at the approach of astorm. There are commonly from 
ten to fifteen “good sap days’? in the sap season, which con- 
tinues about six weeks. After this, in spring, and also in sum- 
mer and the earlier part of autumn, sap continues to flow, but 
it is not rich in saccharine matter. 
The sap is obtained by making an incision with a chisel and 
boring with a small bit,or by boring, with an augur five cighths 
of an inch in diameter, holes inclining upwards to the depth of 
from two to six inches, according to the size of the tree, and 
inserting a spout made of elder, or, most commonly, sumac, the 
pith of which being removed, leaves a tube large enough for the 
purpose. Several holes are so bored that their spouts shall lead 
to the same bucket, and high enough to allow the bucket to 
hang two or three feet from the ground, to prevent leaves and 
dirt from being blown in. The openings are usually made on 
