Evening star., 1928-04-24
THIS AND THAT
BY CHARLES E. TRACEWELL.

| The best use of most garden books
Is to show the ambitious reader how
really little he knows about anything,
how each subject treated Is the study Of
q lifetime.
Thus one may soothe his own lack
with the pleasing knowledge that this
cannot be helped unless he wants to
devote his life to work in particular
field. 1t matters not whether that
field be roses, lilacs, pruning, manuring,
plant propagation or what not.
Hardy Evergreens," a recent addition
to the Farm and Garden Library issued
by the Orange Judd Publishing Co.
will show the sensitive reader how wide
this particular subject is.
The book, by Prof. Frank A. Schrepfer
of the department Of landscape archi-
lecture of the University of Pennsyl-
vania, deals with the planting. growth
and management Of all hardy eVergrcenS
exclusive of the broad-leaved species.
The second chapter. entitled "The
Problem of the Living Plant" is one
of the clearest expositions OF plant
nutrition and growth which we have
ever read, and for that reason we quote
literally here.
It seems that In our garden articles
in this column, from time to time, we
fer saws that ''it is very common
error to believe that plants take their
food from the soil"
What the plants take from the soil,
he points out, lis the raw material.
the salts and water, from which organic
food compounds are formed" We-and
scores of otherS-Stand corrected. But
more Of this later.
"Plants are living organisms. subject
to laws of growth and development as
stringent and memorable as those affect
ing the existence of animals" our au-
thor points out. I'm fact plants are
usually more directly affected by en-
vironmental influences than all but the
lower forms of animal life. Plants are
generally fixed in one place. unable to
move about in search of food, or to
escape adverse temperature and light
conditions. Under these circumstances
plants have developed structures and
habits which enable them to overcome
the handicap of fixed situation.
~ -
"The ever ramifying root system
penetrating into new soil areas. pro-
videS a wider soil area for securing the
necessary mineral salts and the all-in1-
PuIbdllJ Nat(As AtA ~ tAhC AoaAAANh ]AAN
branching top and the arrangement of
the leaves on the twigs exposes the
green surfaces to the action of sunlight
and the moving atmosphere containing
the essential oxygen and carbon d.
oxide"
At this point Prof, Schrepfer takes
us behind the scenes, as 1t were. say
ing: Life, In terms of growth and de-
velopment, is a traffic in energy. The
cells and tissues of plants are made up
Of combinations of inorganic salts water
and gases. The energy consumed in
the formation of new cells, the increase
In the size OF parts, and the produc-
ton of new parts is supplied in the final
analysis by the radiant energy OF the
sun.
This energy is imprisoned and i'm
pounded by plants in their green tissues
in the process called photo-synthesis.
This process is the synthesis of some in
organic salts. gases. water and radiant
energy of the sun into compounds OF
these materials. which serve as the en-
srgy-supplying food for the plants them
selves. and. incidentally. for animals
that eat the plants and are in turn
eaten by other animals, and so on
through the cycle Of life existence. Thus,
plants faced by the necessity of supply
ing food for themselves are the link be-
tween the inorganic materials OF the