Lamoille newsdealer. [volume] (Hyde Park, Vt.) 1860-1877, 1874-03-11
Flow OF San.

some CURIOUS facts seem 10 pc DrOusl
to light in the following, which we fnt
reported in the Mas. Ploughmaa:
"lp the extensive and admirable serie
Of experiment, and observations at tn,
Massachusetts i agricultural College at Am
heIs,, as detailed IN the lecture of Presi
dert Clark beflre the State Board of Ag
r.culiure at Fitchburg, aud designed Il
ascertain the laws III relation. to the flow
or circulation OF sap in different species O
those which flowed had its own time Of be.
ginning, when it seemed to awake from its
winters reposc that the flow steadily in
creased IN quantity and force, us indicated
/ by the weight of sap and the pressure on
a mercurial glagc, until it reached its
maximum, and then gradually declined ;
aud that the composition of.ihe sap of the
scve,a! species differed remarkably, ac-
cording 10 the date of the flow aud espec-
ia Y the time Of its beginning.
The singular periodcity. peculiar to ev-
cry species, demonstrates that the absOrp-
tion of water by the rootlets is not caused
b. osnosc or any other mere physical
forc., but is the result of the specific life,
which impar:s to every plant its distinctive
c arac.cr.
The sugar maple begins to flow in Octo-
Der, reaches its MAXIMUM about the first
of April, and ceases about the middle Of
May. Mr.. II. S. Goodale, of Mount
Washington, Mass, a member OF the Board
Of Agriculture, states that he has made
maple sugar from sap collected in the
mo#ths OF October, November, January,
March, April and May The black birch
begins TO flow the last of March, attains
its maximum the last of April, aud stops
the middle Of May. The wild summer
grape vine com nences about the first Of
May, arrives at its maximum of flow and
pressure about the Goth of May aud ceases
early in June.
The difference in the season of flowing
is, Of course, accompanied by cores
pouding variation in the temperature Of
the soil and the atmosphere, and very
naturally also in the chemical composition
of the sap. Thus the principal ingredient
of maple sap is grape sugar, aud that of
vine sap is mucilage or gum.
These three carbohydrates, cane sugar,
grape sugar and gum, are doubtless chief
~ formed out of the starch which has de-
scended to the root of the plant as the re.
suit Of the previous seasons growth. 1t
seems probable that these transformations
occur IN the sap after the period of activ-
ty begins and in the following order, viz:
Lnsoluble starch, whether deposited in the
cells of the root or previously transferred
u solution to these Of the sters. and there {
stored during the season Of repose, be-
zones soluble gum, the gum becomes un- :,
,rys'allzable grape sugar, and this under ,
avorabe circumstances becomes cane i
ugar. Why then do we find cane sugar
II the maple AMI not in the birch, and 4
Why only gum as the chief ingredient in
he sap Of the vine, and OF those trees
7hich DO not acquire the power Of active ;
bsorptien until the development of their s
udS? Probably because these translor-
nations require time, and the maple alone o.
gorgcd with sap during the six months tf
Intervening between tho fall Of the leaf Il
nd the beginning Of growth in the spring. :: :
his affords ample time fer chemical n
hanges, and seems to have some connec- Il
on with the fact the naples are the only o
ICES from which crystallzable cane sugar b
an be profitably extracted. y
For similar reason, since we find the !;
riches filled with sap for several weeks n
eiore bud begins to expand, We may
easonably expect the formation Of grape t
agar at least in them, and in the north OF il
Europe sweet slrup is obtained by the
Of their sap. :
The spring sap of the vine at the begin !
ing of its motion, about the first of May, +
outains no sugar of any kind, but three d
'ecks later it often acquires a sweetsh b
astc, and then We may fnd trace Of !
rape sugar. At this period the begin !,
ing of vegetable growth is attended by '
ne rapid exha.ation Of the water Of the t
rude sap, and the assimilation of Its gum, a
D The formation of ccllulose, and this is Ii
reciscly the transformation which ordiua-
lily occurs in plants at the beginning Of :
he vegetable season. d