well anchored in the soil, at or near the close of the growing season, pull downward and outward large numbers of bulblets that form around a parent bulb of some kinds of leeks, tulips, star-of-bethlehem, globe hyacinth, and monkshood. The pull of the roots is much greater to one side than downward, because most of the longest roots extend sidewise. Marilaun reports that a certain lawn in Vienna was mown so frequently that tulips could not go to seed, but after twenty years, from a very few bulbs planted near each other, a space twenty paces in diameter was well covered by tulips. And this is one way tulips travel, slow and sure.

5. Roots hold plants erect like ropes to a mast.—Did you ever lift vines of cucumbers, squashes, and the like, where they had rooted at the joints, and observe how forlorn they looked after the operation, with leaves tipped over, unable to remain erect? While growing, the stem zigzags or winds about more or less, and thus enables it to hold the leaves erect; besides, the tendrils catch on to weeds and curl up tight, and the roots at the joints are drawn taut on each side after the manner mentioned above, and act like ropes to a mast to hold the stem in its place, and thus help to hold the leaf above erect.

FIG. 2.—Small tree, "grub," of white oak many times killed back; finally dead at the middle and sprouting on the margins.

6. How oaks creep about and multiply.—Oaks come from acorns; everybody knows that. The nuts are produced in abundance, and those of the white oak send out pretty good tap roots on the same year they fall. Some of the nuts roll down the knoll or are carried about by squirrels or birds, as mentioned elsewhere. Let me tell you one thing that I discovered the white oaks were doing in the sand of the Jack-pine plains of Michigan. In dry weather the dead grass, sticks, and logs are often burned, which kills much or all that is growing above ground. In this way little maples, ashes, witch-hazels, willows, huckleberries, blackberries, sweet ferns, service berries, aspens, oaks, and others are often killed back, but afterward sprout up again and again, and, after repeated burnings, form each a large rough mass popularly known as a grub. The grubs of the oak are well known; the large ones weighing from 75 to 100 pounds each. To plow land where grubs abound requires a stout plow and several pairs of horses or oxen.

A small white oak, after it has been many times killed to the ground, dies in the middle and sprouts at the margins, and finally the main root perishes, and two roots, with branches a little distance apart, support each a cluster of stems above ground.

FIG. 3.—Grub, or remains of a white oak, doubtless at one time much like Fig. 2, but now decayed in the middle, including its main root; sprouting on the margins, farther and farther out after the tops were killed, to the ground.

FIG. 4.—Grub, or remains of a white oak, still older than the one represented in Fig. 3. A hole appears where the tap root has rotted away. The right-hand portion is already dividing, and in time, if often killed back, we might find several distinct oaks as descendants from one acorn.

There can be no doubt that young oak trees slowly move in this manner from one place to another. If in fifty years we have two distinct grubs or branches, three or four feet apart, where the connecting part has finally died out, I see no reason why in another fifty years each one of the two may not again have spread and divided, giving us at least four grubs, or clusters of sprouts, all originally coming from one acorn; and so the matter might go on. This is slow traveling, I admit, but there is nothing to hinder nature from taking all the time she wants.

FIG. 5.—Part of a grub of white oak, still alive and spreading over the ground, the central portions dying, the margins alive and spreading.

CHAPTER III.
PLANTS MULTIPLY BY MEANS OF STEMS.

7. Two grasses in fierce contention.—In growing a lawn at the Michigan Agricultural College, a little Bermuda grass was scattered with June grass, and the struggle has been most interesting. In the spring and for six weeks in autumn, when moisture usually abounds and the weather is cool, June grass thrives and little else is seen. In the dry, hot weeks of July and August, June grass rests and the Bermuda, which continues to spread, assumes control of the lawn, with but little of the June grass in sight. Each struggles for possession and does the best it can, and to some extent one supplements the other, with the result that at all times from spring to fall there is a close mat of living green which delights the eye and is pleasant to the feet that tread upon it. In soft ground, with plenty of room, a bit of quick or quack grass, or Bermuda, will extend in a year three to five feet or more in one direction.

FIG. 6.—Rootstock of quick grass which has grown through a potato, and in this way may be carried to another field or another farm.

June grass, quick grass, Bermuda grass, redtop, and white clover, wherever opportunity offers, spread by means of jointed stems, creeping and rooting at every joint on the surface of the ground or a little way below. These are not roots at all, but true stems somewhat in disguise. Here may also be mentioned, as having similar habit, artichokes, peppermint, spearmint, barberry, Indian hemp, bindweed, toadflax, matrimony vine, bugle-weed, ostrich fern, eagle fern, sensitive fern, coltsfoot, St. John'swort, sorrel, great willow-herb, and many more.

8. Runners establish new colonies.—The spreading of strawberries by runners must be familiar to every observer. In 1894 a student reported that a wild strawberry plant in the botanic garden had produced in that year 1230 plants. Weeds were all kept away, the season was favorable, the soil sandy; but on one side, within a foot and a half, progress was checked by the presence of a large plant of another kind. The multiplication of this plant by seeds, in addition to that by runners, would have covered a still greater area of land. Other plants with runners much like the strawberry are: several kinds of crowfoot,