The Middlebury register. [volume] (Middlebury, Vt.) 1850-1882, 1877-05-04
The Flow ofSap in Trees.


EDIToRs OF REGIsTER.-I noticed an
article in your issue of April 20, headed
GLOW ofSap in Maple Trees" stating
that some time ago, Amherst college
made up its mind that the maple sap
from which sugar was made in the
spring was laid up in the tree the year
before. The experiment tried by the
college may be true, but II does not con-
vince my mind. Ihave made sugar for
more than fifty sugar seasons in success
sion in the south part of Addison coun-
ty. In that time | have observed that
the sugar prophet invariably through
the press each year announces, If the
ground is hard frozen, that the farmers
are expecting to make large quantities of
sugar; If the ground is not frozen, then
small quantities are predicted. This
year, the ground being unfrozen, full
average amount has been made. In the
years 1S43, '55 and 20, small amounts of
sugar were made, yet the ground was
frozen. In 1S43, cold weather lasted till
about the 9th of April, then came q
change to warm sunshine and south
wind two or three days. l had two
hundred trees tapped; boiled up my sap
in less than two days. In 1855, sap be-
gan to flow the 4th day of April and
continued three days. Then the wind
turned south with warm sunshine for
about three days; no amount of freezing
produced sap that year after. In 1870,
Mar. 81, 28,and 20 were warm sunshiny
days, wind south, no flow of sap of any
consequence afterward, yet the ground
froze hard, with number of frosts af-
forwards. When the wind is west and
northwest, with moist atmosphere, we
have our greatest flow of sap. have
known sap to flow few hours with the
south, but that is invariably accompa-
MED with moist foggy, weather. There
was an uncommon flow of sap in the
spring of 1868 for a few days. The
mountain was covered with frost
through the day full two-thirds of the
way down its side. The snow would
pack but little on top; below three
or four inches it was like meal or gray
ell, so hard was it frozen, yet for num-
Der of days, after about three o'clock p.
NJ, icicles would form from the spout to
the bucket each day. From these facts,
L come to the conclusion that the sap
from which sugar is made in the spring
is taken by the tree from the atmos-
phere; that it requires the frosts OF
winter to fit the bark of the tree for ia
king in sap; that dry weather and
sunshine with south wind so contracts
the porousness ofthe bark of the tree as
to unfit it for taking in sap that q
large proportion of sap is In the two
outside grains of the wood in the tree
that the outer grain covers the inner
ones entire each year; that only the
bark on the tree comes in contact with
the atmosphere; that the older the tree
grows the deeper are the inner grains
covered and the less chance for circula.
ton of sap in them; that the draught OF
sap in the spring for sugar is no detri
ment TO the growth of the tree; that
of two vigorous trees of equal size, one
with small top, the other with wide
spreading one, the large top will invari
ably run the most sap.
can see nothing in the Amherst ex-
pertinent to initiate against this theory
All it proves is, that the sap does moi
come from the root in the spring. Might
not the experiment be more satisfactor-
lily tried by thoroughly vanishing few
maple trees at different times during the
fall and winter and let them stand and
tap them in the spring.
Goshen, April 80, 1877.