PLANTS KNOW HOW TO SPREAD
It was not many days after this that the Chief Gardener was digging among his vines, and he called to the children, who came running.
"We were talking the other day," he said, "about the many ways that old plants have of making new ones. See how this black raspberry vine is spreading."
The Chief Gardener pointed to a long branch that had bent over until the end touched the earth. This end had taken root, and now a new little plant was there all formed and ready to grow the coming year.
"There is another just like it," said Davy, "and another—why, there are lots of them!"
"Yes, the vine sends out many of those long slender branches with a heavy little bud at the end of each to weigh it down. Such branches are called stolons, and when the bud touches the earth it sends out roots. Strawberries have runners which do the same thing. You will find plenty of them if you look in the patch."
Davy and Prue went over to the strawberries and found that the vines, now red and brown from frost, had sent out runners, and made little new plants, like the black raspberries.
"You see," said the Chief Gardener, "we pick the berries, which are the seeds, so all berry vines must have some other way of spreading. The red raspberries do it in a different way. They send out runners, too, but they are from the roots, and when the sprouts come up, we call them suckers. Many kinds of plants have suckers, and there are some kinds of trees sprout so badly that they cannot be used for shade."
"What a lot of ways there are for plants to start!" said Davy.
"Suppose we try to think of as many as we can," said the Chief Gardener. "You begin, Prue."
"Seeds and roots and bend-overs and stuck-ins," said Prue. "That's four."
A BLACK RASPBERRY VINE PREPARING TO SPREAD
Davy and the Chief Gardener laughed.
"Well, that is a good start, but there are a good many kinds of roots and 'bend-overs,' and what are 'stuck-ins?'"
"Why, pieces stuck in the ground to grow. Mamma does it with her geraniums."
"Oh, slips! I see. Why, Prue, your answer covers about everything, after all. Now, Davy, suppose we hear from you."
"Well, seeds—that's one. Bulbs, all the kinds, like the three onion kinds, and maybe other kinds, roots like the red raspberries, that make suckers and other kinds of roots, like potatoes, and then all the runners and suckers that Prue calls 'bend-overs,' and slips and grafts and buds."
"Stuck-ins," nodded the Chief Gardener. "Prue was about right after all, for there are so many kinds of each different thing, and so many ways, that I am afraid we should never remember all the kinds and ways. 'Seeds and roots and bend-overs and stuck-ins' take in about all of them, and we are not apt to forget it. If you'll come now, we'll look at some of the kinds of roots."
They went down into the garden, and the Chief Gardener opened a hill of potatoes which had not been dug. Then he picked up one of the potatoes and showed it to Davy and Prue.
"WHAT ARE STUCK-INS?—OH, SLIPS!"
"That kind of a root is called a tuber," he said. "Those little spots on it are eyes, and make the sprouts. You remember we cut the potatoes we planted into little pieces, with one eye on each."
"I remember," said Prue, "and I asked if they had eyes so they could see which way to grow."
"The pieces we planted sprouted, and kept the sprout growing until it could send out roots. Besides the roots, there were little underground branches, and a potato formed on the end of each branch. When the soil and the season are both good there will be a great many of these branches and new tubers, but when the soil is poor and the season bad there will be very little besides roots."
The children followed the Chief Gardener, and dug up a bunch of thick dahlia roots, and he told them how these were really roots, and not tubers, like the potatoes. Then he dug up some sweet-flag, and they saw how the rough root-pieces were joined one to the other, in a sort of chain of roots, and these he told them were root-stalks, and that they kept a store of nourishment for the new plants, in the spring.
"There is a grass," he said, "which has such a root, and every time it is cut it sends up a new plant, so that every time the farmer tries to get it out of his grain-field he only makes more plants, unless he pulls up every piece and destroys it. You see, that grass has to fight to live, and it makes one of the very best fights of any plant I know, except the Canada thistle, which does very much the same thing. And that is what all plant life is. It is the struggle to live and grow and spread. The struggle with men and animals and heat and cold and with other plants. And in the struggle the plants, and especially the weeds, which have to fight hardest, have grown strong and persevering, and have learned a thousand ways to multiply their roots and to scatter their seed."
III