We see that the water is drawn away from the earth broth into the air by the heat of the sun, just as water is drawn from the broth we place on the stove by the heat of the fire; and that when this has happened, the plant’s food is cooked, and is in condition to be eaten.
But this broth does not lose all its water. There is still enough left to carry it back through the leaf into the branches and stem, and even down into the root once more.
In fact, the prepared food is now sent to just those parts of the plant which most need it.
Perhaps it is laid up beneath the bark, to help make new buds which will burst into leaf and flower another year.
Or perhaps it goes down to help the roots put out new branches and fresh root hairs.
Or possibly it is stowed away in such an underground stem as that of the lily, or the crocus bulb, and is saved for next year’s food. Once in a while some of this prepared food is stored in the leaf itself.
When a leaf is thick and juicy (“fleshy,” the books call it), we can guess that it is full of plant food.
Do you recall the Bryophyllum,—the plant we talked about a few days ago? Its wonderful leaves, you remember, gave birth to a whole colony of new plants.
You may be sure that these leaves had refused to give up all the food sent to them for cooking in the sun. You can guess this from their thick, fleshy look, and you can be sure of this when you see the baby plants spring from their edges; for without plenty of nourishment stored away, these leaves could never manage to support such a quantity of young ones.