THE SORTING ACTON OF WATER
A very important action of water is the sorting of the materials it handles. The boulders are left near their place of origin. From the rest of the mass carried, the gravel, the different grades of sand, the flour like silt and finally the fine plastic clay are sorted each in its turn, and laid down each with its kind. Whether these different materials form successive layers of broad, deep areas depends on the size, velocity, and permanency of the flow.
Fitful streams form soils of varied texture such as are seen in the small creek bottoms that drain higher hills. Every rain makes of the stream a raging torrent that over reaches its banks and leaves only gravel and stone in its main course. The result is a changeable soil.
But in the broad, flat river bottom where the current never flows more than 2 or 3 miles an hour and gradually slows down to perhaps still water in back pools, no coarse material is found, only fine sand, silt, and clay. The broad delta of the lower Mississippi River is one of the best examples of this latter process.
The article goes on regarding lakes, oceans and ice. However, fires, earthquakes, volcanoes also affect and change soil through time.
When I look around the little soil around is covered with asphalt and concrete. As a result flooding is an almost everyday occurrence in these down here pastures, as a figure of speech.
Gardening is many things to the many initiated. For your humbleness is a matter of keeping things in perspective. A little bit of this and little bit of that.
Dario apaga la luh.
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