Sacramento daily record-union. [volume] (Sacramento [Calif.]) 1875-1891, 1882-03-25
AGRICULTURAL PAPERS.
4 SERIES PREPARED ESPECIALLY FOR
THE "REcoRD-JNIoN."
ures from the Chair of agricult-
IRE, State University.

ures from the Chair of agricult-
IRE, State University.
ELEVENTH PAPER.
The absorption of food by the root
Is Of the utmost Importance to the plant,
and function which the root is, by It's
dehcacy of structure, rapid growth in
length, and great amount of surface ex-
posed, well qualified to perform. The
young roots are more delicate, and hence
better adapted for the absorption of liquids
than the older ones. 1t was commonly
thought that absorption took place through
the extremities of the roots, or the spongi-
oles, as they were termed. The root tips
have not the power of taking up liquids,
but all other of the younger parts
and tender surface textures of the roots
are constantly absorbing nutriment.
In some perennial plants the older
roots acquire a sort of corky coat
ing or cuticle which is impervioas
to liquids, and which practically prevents
them from performing any nutritive func-
tons. The length of the root or the dis
lance in direct line from its extremity to
the base of the stem cannot be taken as
just criterion of its efficiency. A root
much shorter but which has more lateral
branches, may present much larger sur
face to the soil, and hence have greater
absorptive power. The aggregate absorb
ing surface should always be taken into
account when comparing the relative eff
cheney of roots The growth of roots is
controlled largely by the composition and
tilth of the medium or soil in which they
are buried. In poor soils, sand bed for
instance, the roots are very long, slender
and almost thread like, and have no, or but
very few, lateral branches. In this case
the root has been obliged to penetrate to a
great distance in order to find enough nu-
tritive matter to maintain the life and
growth of the plant. In moderate good
soil
THE MAIN ROOTS
Are much shorter, with the lateral roots
much more numerous. If the soil is ex.
ceptionally rich, just il proportion will be
the multiplication Of rootlets. Masses of
manure, if in reach of the roots, are soon
covered with a complete mass of rootlets.
The greatest development of the roots al
ways takes place in the immediate vicinity
OF the nutritive matter. If stratum of
clay or sand be interposed between the
plant and clod Of manure the roots will
be fibrous and attenuated while going
through this unfertile stratum, but as soon
as the manure is reached they multiply and
ramify almost indefinitely until they have
absorbed and transmitted through their
slender channels all of the available pour-
ishment. Although no very definite rela-
ton exists between the foliage of tree
and the position of its roots, yet there
appears to be some connection between
the development CT foliage on given side
of the tree and the development of the
corresponding roots. 1t is surprising
and not generally known how
large a quantity of roots is put
forth by many plants. No adequate idea
of their number or length can be obtained
by pulling up plant, even though it be in
very loose and friabie soil. Schubert
made an exhaustive set of experiments on
this eubjsct, and met with astonishing re-
suits. His method was TO excavate per-
pendicular cut as deep as he wished to go,
and then to wash away and remove the
dirt by turning a gentle stream of water
against it. By this means the mass OF the
roots were laid bare and left intact. He
found the roots of rye, beans and garden
peas to present the appearance of mat or
felt OF white fibers to the depth of four
feet. Forty-seven days after sowing he
found the roots of winter soBn wheat at a
depth of seven feet, and roots of winter
sown clover or COLA were from three to
four feet long. He found the roots of one
year-old clover at the depth of 3 5 feet,
while the depth of roots of twe-year old
clover was only six inches more. He gives
the relative amount OF roots to the whole
plant, in the dry stalks, of winter wheat,
examined the last of April and again a
month later-to be respectively 40 and %
per cent; of rye examined in April,
az 81 per cent, and peas, four
weeks after sowing, and again at bios
soming as A and "a per cent. of dry weight.
We thus see that the relative proper
ton of roots decreases with the age of the
plant. This is caused, not by the falling
off in the growth of the roots, but by the
much greater corresponding development
of the stem during the latter stages of
growth. Hellriegel also made a number of
experiments on the roots of the grains. He
found that from 20 to 80 roots branch out
from the base of the stem, and, as johnson
says, g observed that these roots at their
point of issue have diameter of .04 of an
inch, but little lower their diameter d.
minishes to about .0l of an inch. Retain
ing this diameter, they pass downward, di-
viding and branching, to certain depth.
From these main roots branch out inumer-
able side roots, which branch again, and so
on, filling every crevice and pore of the
soil" By weighing the lengths of selected
average portions, and then comparing their
weights with the weight of the entire
mass of roots he was enabled to calculate
approximately
THE LENGTH OF THE ROOTS.
By this means he fourd the length of
the roots of vigorous barley plant to be
l2S Rhenish feet, and of an oat plant $50
Rhenish feet. As one would suppose
might be the case, he found that the ag-
gregate length of the roots was influenced
by the quality of the soil. In one case,
in rich, porous garden soil, he found the
length to be l2S feet, while the roots of
the same kind of plant grown in
coarser and more compact soil only fur.
nished so feet of roots. In most cases it
is only with the aid of the microscope that
we can appreciate the real absorbent sur.
faces of roots. The roots of some plants
onions and other bulbs-are fibrous, per-
fectly smooth and unbranched throughout.
Other plants have roots which are numer-
ously branched, and which branches are
covered with minute root hairs, often i'm
perceptible to the naked eye. These root
hairs are cylindrical elongations of the
external root cells, and when their super
| fetal area is taken into account it is found