Note 299 — Chapter III · (continued 4)

Although the economy of the forest has received little attention in the United States, no lover of American nature can have failed to observe a marked difference between a native wood from which cattle are excluded and one where they are permitted to browse. A few seasons suffice for the total extirpation of the "underbrush," including the young trees on which alone the reproduction of the forest depends, and all the branches of those of larger growth which hang within reach of the cattle are stripped of their buds and leaves, and soon wither and fall off. These effects are observable at a great distance, and a wood pasture is recognized, almost as far as it can be seen, by the regularity with which its lower foliage terminates at what Ruskin somewhere calls the "cattle line." This always runs parallel to the surface of the ground, and is determined by the height to which domestic quadrupeds can reach to feed upon the leaves. In describing a visit to the grand-ducal farm of San Rossore near Pisa, where a large herd of camels is kept, Chateauvieux says: "In passing through a wood of evergreen oaks, I observed that all the twigs and foliage of the trees were clipped up to the height of about twelve feet above the ground, without leaving a single spray below that level. I was informed that the browsing of the camels had trimmed the trees as high as they could reach."—Lullin de Chateauvieux, Lettres sur l'Italie, p. 113.

The removal of the shelter afforded by the brushwood and the pendulous branches of trees permits drying and chilling winds to parch and cool the ground, and of course injuriously affects the growth of the wood. But this is not all. The tread of quadrupeds exposes and bruises the roots of the trees, which often die from this cause, as any one may observe by following the paths made by cattle through woodlands.