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 CHAPTER XVII

HOW PLANTS CLIMB

We have found that plants struggle or contend for a place in which to live. Some of them become adapted to grow in the forest shade, others to grow on other plants, as epiphytes, others to climb to the light. Observe how woods grapes, and other forest climbers, spread their foliage on the very top of the forest tree, while their long flexile trunks may be bare.

There are several ways by which plants climb, but most climbers may be classified into four groups: (1) scramblers, (2) root climbers, (3) tendril climbers, (4) twiners.

Scramblers.—Some plants rise to light and air by resting their long and weak stems on the tops of bushes and quick-growing herbs. Their stems may be elevated in part by the growing twigs of the plants on which they recline. Such plants are scramblers. Usually they are provided with prickles or bristles. In most weedy swamp thickets, scrambling plants may be found. Briers, some roses, bed-straw or galium, bittersweet (Solanum Dulcamara, not the Celastrus), the tear-thumb polygonums, and other plants are familiar examples of scramblers.

Root Climbers.—Some plants climb by means of true roots. These roots seek the dark places and therefore enter the chinks in walls and bark. The trumpet creeper is a familiar example (Fig. 36). The true or English ivy, which is often grown to cover buildings, is another instance. Still another is the poison ivy. Roots are