Sandy Soils, Sandy Loams
Sandy Soils
Soils containing 80 per cent, of sand and less than 10 per cent,
of clay are called sandy. These soils are usually poor in plant food and are leachy,
especially if the sand grains are large. The finer the sand the more valuable is the
soil, as a rule. In dry weather crops on sandy soils are quickly parched. These soils
absorb little if any water from the air. On the other hand a sandy soil dries out very
soon after a rain, so that it can be worked quickly. Moreover, a sandy soil is warm,
because the large quartz grains hold heat well; they are miniature soap stones. If kept
wet and if enriched, sandy soils respond with large crops, especially if the farmer fills
them with humus. Heavy dressings of barnyard manure have a very beneficial effect upon
sandy soils, not merely because manure enriches them in plant food, but more particularly
because the humus in it clogs the large spaces between the sand grains, making the soil
less porous. A green crop plowed under has the same effect. Manures and fertilisers
should not be applied to sandy soils long before the plants need them.
Some of the most valuable early truck and fruit lands, notably in Delaware and New Jersey
and elsewhere along the Atlantic seaboard, are sandy soils that have been built up and
given greater body and life by green manuring. Soils known technically as "Norfolk sand,"
the "Fresno sand" of California, and the "Miami sand" of inland regions are other
examples. They are especially valuable where earliness is essential and are adapted for
quick-growing crops, particularly Irish and sweet potatoes, peas, peppers, watermelons,
canteloupes; also early fruits, especially strawberries and peaches. They are too light
for wheat, oats, rye and other general farm crops. The main point to look after in
handling a sandy soil is to fill it with humus. It should not be plowed deeply, as this
loosens the soil still more. Heavy rolling compacts the grains and is often very
beneficial on soils of this type. Liming will bind the particles together, making the
soil more compact.
Sandy Loams
When a soil contains from 60 to 70 per cent, of sand it is
commonly called a sandy loam; while a soil that is 70 to 80 per cent, sand is called a
light sandy loam. The gradations between the two are insensible. The balance of these
soils is clay silt and humus. These are valuable soils for market garden crops, because
they are early, hold a fair amount of water and fertility and are easy to work. Sandy
loams are especially desirable for all the trucking crops mentioned as succeeding on
sandy soils and are fairly good for general farming crops, although rather light for this
purpose. Corn, cotton, rye, potatoes, and the common garden vegetables, as melons,
squashes, turnips, tomatoes, beans, etc., enjoy this type of soil. Clover and alfalfa
will do well upon it, provided the soil is deep; black raspberries and peaches also
thrive upon sandy loams. However, they are pre-eminently vegetable gardening soils. In
handling these" soils the important thing to do is to remedy their chief defects, which
are leachiness, and, as a consequence, deficiency in available plant food. They need to
be fertilised highly and are likely to be benefited most of all by stable manure, which
corrects both defects. Usually it is not best to plow them in the fall and leave them
over winter without a cover crop, because much plant food will be lost by leaching.
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