Gravelly And Stony Loams, Peat And Muck Soils
Gravelly and stony loams
These are sandy loams, clay loams, or loams with an
admixture of gravel or stones ; all pieces of rock from 1-25 of an inch in diameter up to
two or three inches are gravel — larger pieces are stones. Gravelly and stony loams are
most common in the North, especially in the Northeastern states, where they were formed
by the work of glaciers. Most of the pieces of rock are worn smooth. The presence of a
large quantity of small stones in a soil makes it warmer, for rock absorbs heat more
freely than soil, and loses it more slowly, thus keeping the soil warmer at night. If the
stones are numerous and large, however, the increased difficulty of tillage may more than
offset the advantage of earliness. For this reason a gravelly loam is usually more
valuable than a stony loam. A gravelly or stony sandy loam is sought when extreme
earliness is desired. Some of the most profitable strawberry plantations in New York are
on this type of soils. As a rule they are better adapted for fruits, especially small
fruits, than for staple farm crops.
Peat and muck soils
Peat and muck are the black soils produced when a
luxuriant growth of plants decays slowly under water for many years. When the plants are
but partially decayed, so that the soil is very spongy and fibrous, it is called peat.
When decay has progressed further, and especially when the soil is alternately submerged
and exposed to the air, becoming finer, blacker and no longer fibrous, it is called muck.
Muck is an advanced stage of peat. Both are passing through the same process by which coal
has been formed. Peat and muck swamps and bogs are found all over the eastern United
States, and in many parts of the West except in the arid regions. Most of our fresh water
marshes are muck or peat. They are not so numerous here, however, as in many parts of
Europe, especially in Ireland, one-tenth of which is said to be peat bogs. These soils
are being made to-day, where shallow lakes, ponds, streams, and swamps are being filled
by the growth of plants, especially the sphagnum moss; but less peat is being made now
than during a period in the earth's history when rainfall was more abundant.
The Value of Peat and Muck Soils.
The value of peat and muck soils for
farming depends chiefly upon the amount of mineral matter they contain and upon their
drainage. Some of these soils are nearly 100 per cent, humus, others are but 30 per cent,
humus. Considerable fine rock or mineral soil may be blown upon peat or muck land; the
more of this the better. Muck, being further advanced in decay than peat, is more apt to
become serviceable as a farm soil than peat; it is, moreover, more compact and usually
contains more mineral soil, having been above water longer. Many muck and some peat soils
need only to be drained in order to become valuable for cropping. Thousands of acres of
land, especially fresh marsh land, have been reclaimed in this way. In Michigan and Ohio
reclaimed swamp lands are largely used for growing celery and onions. Open ditches are
most commonly used for this purpose, these soils being so loose that tile drainage is
usually impracticable at first, except for the most earthy mucks. The result of drainage
is to lower the water table so that air can penetrate the soil.
Many peats, and some mucks in which the decay has not progressed far, do not make good
farm land, even after they are drained; they become very dry and chalky, having scarcely
more power to draw up the free water beneath by capillary action than a pile of chips.
Not until several years after drainage, when the fibrous matter has been broken down and
made into fine soil, are some peat and muck soils able to grow profitable crops. When
well drained and sufficiently fined to permit the free movement of water upward, these
soils are especially suitable for cabbage, cauliflower, celery and peppermint. On the
finest of mucks the grasses and a variety of vegetables are successful.
In southwestern Massachusetts, and in New Jersey, Wisconsin, Michigan and some other
sections, peat and muck bogs are ditched, the surface covered with 3 to 6 inches of sand,
and then planted with cranberries. In handling muck and peat soils one must remember that
they are largely humus and always contain a large per cent, of nitrogen, the chief
fertilising element produced by the decay of vegetation. In fact, muck often contains as
much nitrogen as barn manure, although but little of this is in available form, being in
the form of organic nitrogen. These soils usually need fertilising with the mineral plant
foods — potash, phosphoric acid, and lime. Wood ashes are especially beneficial to muck
soils. As a rule they do not respond to manuring as satisfactorily as soils that contain
more mineral matter.
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