ONE PLANT HELP
A thousand acres of land on Cape Cod were once blown away. This wind excavation was ten feet deep. It was not an extraordinary wind, but extraordinary land. It was made of rock ground up into fine sand by the waves on the shore.
In all the deserts of the world the wind blows the itinerant sand on its far journeys. If the wind is moderate it heaps the sand up into little hills, some of them six hundred feet high, around any obstruction, and then blows the sand up the slanting face of the hill and over the top, where it falls out of the wind on the leeward side. In this way the hill is always traveling. In North Carolina hills start inland, and travel right on, burying a house or farm if it be in the way, but resurrecting it again on the other side as the hill goes on. Anyone may see these hills at the south end of Lake Michigan, as he approaches Chicago, west of San Francisco, all along up the Columbia River--the sand having come on the wings of the wind from the coast.
But to see the whole visible world on a march one needs to go to a really large desert. The Pyramids and the Sphinx have been partly buried, and parts of the valley of the Nile threatened, by hordes of sand hills marching in from the desert; cities have been buried and harbors filled up. Many of the harbors of the ancient civilizations are mere miasmatic marshes now. This is partly in consequence of the silt brought in by the rivers; but where the rivers do not flow in it is because the sand blows in along the shore. Harbors are especially endangered when their protection from the waves consists of a bank of sand, as on Cape Cod and the Sandy Hook below the Narrows of the harbor of New York.
How can man combat part of the continent on the move, driven by the ceaseless powers of the air? By a humble plant or two. The movement of the sand hills that threaten to destroy the marvelous beauty of the grounds of the Hotel del Monte at Monterey is stopped by planting dwarf pines. The sand dunes that prevent much of Holland from being reconquered by the sea are protected with great care by willows, etc., and the coast sands of parts of eastern France have been sown with sea pine and broom.
The tract of a thousand acres on Cape Cod had been protected by humble beach grass. Some careless herder let the cows eat it in places, and away went part of a township. It is now a punishable crime on Cape Cod to destroy beach grass.