A General View
Stony loams Soils containing more than 50 per cent stones over 1 inch in diameter. If remainder is suffi­ciently fertile, this soil type may have garden­ing value, although it will be hard to work.
Gravels Soils with over 50 per cent gravel and much sand. Practically no garden value.
Sands Soils with more than 75 per cent sand. Low garden value.
Fine sandy loams Soils with 50 to 75 per cent fine sand mixed with much silt and some clay. Fairly good garden soils.
Sandy loams Soils with 50 to 75 per cent sand and much silt, some clay. Among the better light garden soils.
Loams Soils with 35 to 50 per cent sand mixed with much silt and some clay. Most of the better garden soils fall in this class.
Silt loams Soils with more than 50 per cent silt and less than 15 per cent clay. Are too "tight" to be good soils without some modification.
Gay loams Soils with 15 to 25 per cent clay, much silt and little sand. Usually are good garden soils if not worked when wet.
Clays Soils with more than 25 per cent clay, usually with much silt. Can be good if handled properly.
Mucks Soils with 15 to 25 per cent partially decomposed organic matter with much clay and silt. Good for certain crops, but modification is usually needed for general garden use.
Peaty loams Soils with 15 to 35 per cent organic matter mixed with much sand and some silt and clay. If acid, are good for broadleaved evergreens.
Peats Soils with 35 per cent or more organic matter, mixed with some sand, silt and clay. Need more mineral matter to be suitable for garden use.

Soil type has to do with mechanical makeup of soil. Type does not give much clue to the value of a given soil for growing plants. By habit we associate loams with rich soils, yet certain loams may be poorer than some clay or sandy soils.

Soil type concerns you in three vital ways. First, many recommendations for applying fertilizer, for treatments to adjust pH (acidity-alkalinity), and for other applications of chemical substances to soil give different rates for clay, sand, and other types. Second, a knowledge of texture-types gives some clue as to how well a soil will hold fertility. (Fall feeding is possible for a lawn on clay loam soil, for example, where this would be unsuccessful on a light sandy loam.) Third, knowing your soil type will often tell you in advance whether it will drain well or will puddle and wash under heavy rains.

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