WHAT IS COMPOSTING?
Composting of organic wastes is an old art, probably as
old as man's tilling of the soil. the good gardener never
entirely lost sight of it. The scientific age with its
teachings of mineral deficiencies and fertilizers looked
down on composting for a while, only to discover in time
that without organic matter in the soil minerals alone will
not solve the problems.
Composting without a bacterial starter is found all
through history. It would be ignoring scientific progress
if we were not to investigate the use of bacterial culture
especially suited to this purpose. Those familiar with the
practice of fermentation in science and industry know very
well controlled fermentation works economically and
successfully to produce end material excelling in quality.
Thus, composting has evolved to become a new skill to be
learned. The rules of small composting in the home/gardner
or on the farm have been well publicized in recent years.
Practice has also shown that when scientific procedures are
used, the compost pile can rot down to a fine humus in half
or less the time that was needed when following the old well
trodden path. The purpose is to produce humus and to
incorporate this humus into the soil. Humus as it derives
from decaying plants, refuse and manure is not fertilizer in
the sense of the word as it is used today. It should be
realized that not all decayed or broken down organic matter
is compost. Compost is more correctly defined as a digested,
earthy matter having the properties and structure of humus.
One argument from the plant food and fertilizer camp against
the use of this material is that there is not enough compost
humus available to sashays the needs of a modern intensified
agriculture. This is true.
Organic matter is only a small fraction of the total material
that makes up the soil-between 1% and 8%. Yet it is absolutely
essential to the sustenance of the soil life and fertility.
Organic matter refers to dead plant and animal residues of all
kinds and in all stages of breakdown or decay. Inseparable from
these decaying dead residues are the living microorganism that
decompose, or digest, them.
Microscopic life forms (bacteria and fungi) in the soil
perform this recombining process. The result is humus. The
result is humus. Heat energy is liberated during the process
and this is the warmth felt in the compost pile. Most of the
decomposition involves the formation of carbon dioxide and
water as organic material is broken down. As the available
energy is consumed, the microbial activities slow down and
their numbers diminish, the pile cools. Most of the remaining
organic matter is in the form of humus compounds. As humus is
formed, nitrogen becomes part of its structure. This
stabilizes nitrogen in the soil, because the humus compounds
are resistant to decomposition. They are worked on slowly by
soil organisms, but the nitrogen and other essential nutrients
are protected from rapid salability and dissipation.
Humus also acts as a site of nutrient absorption and exchange
for plants in the soil. the surfaces of humus particles carry
a negative electrical charge. Many of the plant nutrients, such
as calcium, sodium, magnesium, potassium, and most trace
minerals carry a positive electrical charge in the soil solution
and are thereby attracted and adhere to the surface of the
humus. Some of the plant nutrients are not positively charged,
such as phosphorus, sulfur, and the form of nitrogen that is
available to plants. Fortunately, a good supply of these
nutrients becomes available to plants through biological
transformations in the compost pile and soil.
As plant roots grow through the soil in search of nutrients,
they feed off the humus. Each plant root is surrounded by a
"halo" of hydrogen ions which are a by-product of the roots
respiration. These hydrogen ions also carry a positive
electrical charge. The root actually "bargains" with the humus,
exchanging some of its positively charged hydrogen ions for
positively charged nutrient ions stuck on the surface of the
humus. An active exchange is set up between humus and roots.
The plants "choose" which nutrients they need to balance their
own inner chemistry.
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