If a tree or a vine has a little less succulence than its neighbor or a little less vital impulse, nature calmly watches it pounced upon and extinguished. No one “compassionately tries to save the unfit from the consequences of their unfitness.” Having endowed this prolific land, the lavish elements can withdraw and survey unmoved the scattering showers of seeds, that prodigal industry of plants in busily perfecting seeds which will never be given an opportunity to grow. So little chance has a seed that new attempts at life are more secure if supplied by the energy of the parent stem. The elements are not responsible for the death-struggle of vegetation which results. As far as they are concerned, each seed that falls and each little shoot that springs upward would be given an equal chance. But every form being equally favored, its neighbors contest its right to live. Coöperation to make life possible at all, only begins when united force is needed to conquer a common foe. Life here is for viper and vampire as well as for butterfly, and the parasite has an equal chance with the benevolent vine. It is a battlefield where militant nature fights in civil warfare through the ages. Plants once given birth demand the right to make the most of their own particular form of life, fighting for sun, fighting for air, fighting for the right to live. Ironically enough, warfare is fiercest between forms most closely allied. “They interlace, strangle, and devour each other.” Parasitic alliances are possible only between very divergent forms, each benefiting by the use of what the other does not need. Parasites are leapt upon by other parasites; there is strife even among them. Forever fighting with each other, they all suffer equally from hereditary enemies descending from above or creeping up from below, capturing by attack or poisoning by stealth. Plants not only crowd their neighbors out of the soil, they seem to dispute the air as well. Each begrudges the other a breathing space. The ingenuity of nature is taxed to invent compensations to each for lack of what it has a right to expect as its due. An impenetrable disguise of buttresses is substituted for roots and want of underground space. Air-roots drop from branches. Smaller trees, adapted to the dimness, live in the shade of larger ones. Nature uses every subterfuge, restrained by nothing known as customary. Plants maintain a life whose pertinacity we have no scale for measuring. Each asserts its own individuality and insists upon it with inexhaustible energy. Each is convinced of its own desirability, convinced it was intended to live, proclaiming that intention to the death of its neighbor.