e all the work these
energetic little chlorophyll bodies are doing, we should be amazed.
"You will remember that I told you some plants could take the very
necessary chemical nitrogen from the air; most of them, however, must
get it from the soil. And so again this from the soil solution is worked
over into available food.
"After all we must not fail to see that water is most important. It
floats all the important food elements to the leaves for the work to be
done there. The food carbon, of course, is an exception to this rule and
I will say again in certain cases nitrogen is, also.
"Thus you boys and girls now understand how necessary it is that a soil
should be of the right texture to hold water. If it is not, it must be
helped to be so. Sand, you will remember, had to be doctored to hold
water. Clay needed treatment in order to make it quit its bad habit of
baking out.
"Here is a rather interesting experiment set up by Josephine and Ethel.
Look at the first piece of apparatus--a tumbler partly full of water, a
piece of cardboard over the top of the tumbler, and passing down through
a hole in the cardboard a piece of plant just stem stripped of leaves,
and finally a second tumbler clapped over the first. The second piece of
apparatus is exactly like the first, only that the stem, one end of
which is in the water, has leaves on the other end. Notice that the
upper glass in the second case has moisture on it. The upper tumbler of
the other set is perfectly dry. Whence, then, came the moisture? It
must, of course, be the leaves which gave it off, since they represent
the only difference in the two pieces of apparatus.
"I wish we might go on with whole sets of experiments, but for that we
have not time.
"You understand a little of the mission of root, stem and leaf. The root
does a good work in holding a plant in place. It is the foundation
material of the plant. There is much, much more to be learned about all
these subjects. This little is just to open your eyes to the wonders of
the work each plant is performing all the time.
"I said I would show you some magic. Well, this magic has to do with
plant improvement. It is not much of a trick to raise a plant, but it is
a great one to be able to improve that plant.
"Let me tell you of a friend of mine whom we will call Rodney, because
that is his real name. One day Rodney noticed the gardener doing
something with a little flat knife to a pansy. Then he tie
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