  “Some time ago,” said Uncle George, “I promised to tell you something about how plants arm themselves. And here, in this hedgerow, we have some good examples of armed plants.” “There is the stinging nettle,” said Tom, pointing to a large patch at the roadside. “The stinging nettle is certainly well protected,” said his uncle. “You have only to touch any part of it lightly with your hand to find that out. Every part of the plant is covered with small needle-shaped hairs. “When your hand touches a nettle—unless you grasp it tightly—the sharp hair pierces the skin. It’s brittle point breaks off and the poisonous juice is poured out.” “Why is the nettle covered with these horrid stings?” asked Frank. “To save it from being eaten up, of course. The nettle is a tender and juicy plant, and, if it were not for its stings it would soon disappear altogether. “Now, here is another armed plant, the blackberry or bramble. The stem and also the backs of the leaves are covered with large curved prickles. These prickles not only protect the plant from grazing animals, but they help it to climb and scramble up walls and hedges. “If you try to pull a bramble branch down out of the hawthorn hedge, you will find it rather difficult, for its large prickles are all turned one way. They are really sharp hooks.” “Here is a wild rose bush. It is also covered with large hooked prickles,” said Frank. “Yes, Tom, and, like the bramble, it threads its way among stronger and taller plants. “The wild gooseberry growing close beside it is also armed with prickles. But the prickles of the gooseberry are for protecting its tender leaves. It is not a climbing plant like the rose and bramble. The raspberry also is covered with many sharp little prickles. There is a clump of these plants growing at the other side of the road. Let us cut off a small branch of each of these plants and take them home.” Armed Plants.
“This is the most prickly plant of all,” said Frank, as he halted before a huge thistle. “You can scarcely touch it without getting severely pricked.” “The thistle is well armed,” said Uncle George. “There are sharp prickles on its leaves, on its stem, and on its flowers.” As they walked down the road they came upon a mass of whin bushes. “Here,” said Uncle George, “we have a plant which has turned its leaves into sharp spines.” He bent down and pulled up a tiny plant which was growing under the larger gorse bushes. “Look at this little plant, boys. This is a young whin plant.” “But it is not a bit like the whin, Uncle George,” said Tom. “Its leaves are soft and flat. They are more like clover leaves. There are no spines or prickles on this little plant.” “That is so, Tom; but still it is a young whin plant. Young Whins. “There are a great many of these young whins growing under the older bushes. Let us take a few of them home. If we grow one of them in a pot, and supply it with plenty of water, we will find that it will never produce sharp prickles.” “That is very wonderful,” said Frank. “It is,” said Uncle George, “and it teaches us something of the whin’s history. Like the nettle, the whin is “It shows us that many, many years ago the whin was a soft-leaved plant like the clover. It grew in moist soil. But by and by other plants invaded the land. These plants grew more quickly than the whin, and choked it out of the rich moist soil. Forced to grow upon bare hill-sides and commons, the soft-leaved juicy whin would be destroyed by grazing animals if it did not arm itself with sharp spines. “Here is the blackthorn or sloe. It bears many hard, sharp-pointed spines. Yet, if we grow a sloe plant in the garden, we find that its sharp spines gradually disappear. They become branches bearing leaves and flowers. “But plants have other ways of protecting themselves against animals. Look through the hedge into the meadow and you will notice that while the grass has been eaten bare, there are other plants which have been left to grow up untouched. Buttercups grow up all over the field, and tall ragwort plants. How is it that the cows do not eat these plants? They are not armed with spines or prickles. “They protect themselves in another way. They contain bitter or poisonous juices. No cow will eat a buttercup. If it did so it would be ill and uncomfortable for a time. “I want you to notice, boys, that—with the exception of those plants, like the bramble and wild rose, which Exercises on Lesson IX.
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