Vermont watchman and State journal. [volume] (Montpelier, Vt.) 1836-1883, 1879-08-27

dents OF common plant ashes. But not
one of them exists in an uncombined state,
either in the growing plant or in its ashes.
The substances which they form by com.
bination are numerous. A number Of them
have been already mentioned in previous
chapters. More will be alluded to hereafter.
Quesiion-By what general name are the
compounds derived from these elements
known in agriculture
Answer-They are called mineral plant
food
Question-How do plants partake of this
food?
Answer-They draw it in from the SOIL
dissolved in water. They do this by means
of the finest divisions of their roots, called
"root hairs"
Question-What is this watery solution,
when taken in by the plant called
Answer-The crude or ascending sap.
Question-What becomes of it?
Ansper-It ascends to the leaves, where it
is combined, by the action of sunlight, with
the aerial or volatile plant-food taken in by
the leaves.
Question-What name is given to this COM
bination
AnsDer-The elaborated or descending sap.
Question-Whst becomes of it2
Answer-It is transported along the hol-
low tubes and cells of which every plant is
made up to every portion, and from it are
cd oil vuhi oh
constitute the growth of the plant.
Question--Are every one of these minerals
necessary to the growth of plants?
Answer-The ash of different plants is
not exactly alike, yet most of these minerals
are found in greater or less proportion in
the ashes of every cultivated plant. As to
the necessity of the presence of all of them
as found in the ashes, that is not quite set
tied. How much selective power the roots
exercise is not known. If the roots take up
the soil water with all that is dissolved in
it, it follows that some substances may be
taken up that are not needed at all, and of
others that are needed more may be taken
up than is necessary for the growth of the
plant As the sap all passes through the
leaves, much of this surplus is deposited in
the leaf tissue, and is thus thrown off when
the leaves fall. A large quantity is also de-
posted in the bark, but this cannot be con-
sidered useless, because it forms an outer
coating and protection to the plant. Among
the substances taken up freely by plants the
compounds of silica are thought not to be
necessary to the thrift of the plant, but this
cannot be regarded as quite certain. Lime
is probably often taken up in excess.
Quesiion--What would be the effect Of tbs
entire absence in the soil of any of the nee
essary minerals contained in the ashes oil
any plant upon growing plants of the same
kind
Answer-The seed would germinate but
the plant would perish before reaching
maturity.
Quesiion-What would be the effect Of I
short allowance of any necessary minera
upon such growing plant
Ans~er-The growth would be weak ant
the crop small.
Question-How does full supply of neces
sary minerals affect the growth of plant
Answer-It gives it full and thrift,
growth, provided these minerals are not onl,
abundant but in q soluble state.
Quesiion-What do you mean by "a sol
uble state 2"
Answer-lt was said above that the mir
eral food of plants is taken up fiom the sol
dissolved In water. Unless the mineral |
soluble in water, therefore, the effect upo
the plant would be the same as though !
were not present at all. ,HH
Question--How are these minerals mad
soluble .f.I Dol
Ansper-Nearly all OF them are at leas
slightly soluble, at all times, in the water G
the soil, and those which are least solubl
are made more so by tillage, which expose
them TO the action Of the air, water an
frost. The continuous growth Of vegetatio
upon the soil, by which these minerals al
accumulated in plants which die and ia
back upon the ground, also furnishes SUI