Next spring when you find in the woods the little yellow bells of the Solomon’s seal, I think you will have the curiosity to dig down and find out the age of some of these plants.
Another plant with an underground stem is the beautiful bloodroot. As its name tells you, this so-called root contains a juice that looks something like blood. Such underground stems as those of the Solomon’s seal and bloodroot are called “rootstocks.” Rootstocks, corms, and bulbs are all storehouses of plant food, and make possible an early flowering the following spring.
ABOVE-GROUND ROOTS
But before we finished talking about roots we were led away by underground stems. This does not matter much, however, for these underground stems are still called roots by many people.
Just as stems sometimes grow under ground, roots sometimes grow above ground.
Many of you know the English ivy. This is one of the few plants which city children know quite as well as, if not better than, country children; for in our cities it nearly covers the walls of the churches. In England it grows so luxuriantly that some of the old buildings are hidden beneath masses of its dark leaves.
This ivy plant springs from a root in the earth; but as it makes its way upward, it clings to the stone wall by means of the many air roots which it puts forth (Fig. [116]).
Our own poison ivy is another plant with air roots used for climbing purposes. Often these roots make its stem look as though it were covered with a heavy growth of coarse hair.
