Sir Albert Howard's Indore Method
Nineteenth-century farmers and market gardeners had much practical
knowledge about using manures and making composts that worked like
fertilizers, but little was known about the actual microbial process
of composting until our century. As information became available
about compost ecology, one brilliant individual, Sir Albert Howard,
incorporated the new science of soil microbiology into his
composting and by patient experiment learned how to make superior
compost
During the 1920s, Albert Howard was in charge of a government
research farm at Indore, India. At heart a Peace Corps volunteer, he
made Indore operate like a very representative Indian farm, growing
all the main staples of the local agriculture: cotton, sugar cane,
and cereals. The farm was powered by the same work oxen used by the
surrounding farmers. It would have been easy for Howard to
demonstrate better yields through high technology by buying chemical
fertilizers or using seed meal wastes from oil extraction, using
tractors, and growing new, high-yielding varieties that could make
use of more intense soil nutrition. But these inputs were not
affordable to the average Indian farmer and Howard's purpose was to
offer genuine help to his neighbors by demonstrating methods they
_could_ easily afford and use.
In the beginning of his work at Indore, Howard observed that the
district's soils were basically fertile but low in organic matter
and nitrogen. This deficiency seemed to be due to traditionally
wasteful practices concerning manures and agricultural residues. So
Howard began developing methods to compost the waste products of
agriculture, making enough high-quality fertilizer to supply the
entire farm. Soon, Indore research farm was enjoying record yields
without having insect or disease problems, and without buying
fertilizer or commercial seed. More significantly, the work animals,
fed exclusively on fodder from Indore's humus-rich soil, become
invulnerable to cattle diseases. Their shining health and fine
condition became the envy of the district.
Most significant, Howard contended that his method not only
conserved the nitrogen in cattle manure and crop waste, not only
conserved the organic matter the land produced, but also raised the
processes of the entire operation to an ecological climax of
maximized health and production. Conserving the manure and
composting the crop waste allowed him to increase the soil's organic
matter which increased the soil's release of nutrients from rock
particles that further increased the production of biomass which
allowed him to make even more compost and so on. What I have just
described is not surprising, it is merely a variation on good
farming that some humans have known about for millennia.
What was truly revolutionary was Howard's contention about
increasing net nitrates. With gentle understatement, Howard asserted
that his compost was genuinely superior to anything ever known
before. Indore compost had these advantages: no nitrogen or organic
matter was lost from the farm through mishandling of agricultural
wastes; the humus level of the farm's soils increased to a maximum
sustainable level; and, _the amount of nitrate nitrogen in the
finished compost was higher than the total amount of nitrogen
contained in the materials that formed the heap._ Indore compost
resulted in a net gain of nitrate nitrogen. The compost factory was
also a biological nitrate factory.
Howard published details of the Indore method in 1931 in a slim book
called _The Waste Products of Agriculture. _The widely read book
brought him invitations to visit plantations throughout the British
Empire. It prompted farmers world-wide to make compost by the Indore
method. Travel, contacts, and new awareness of the problems of
European agriculture were responsible for Howard's decision to
create an organic farming and gardening movement.
Howard repeatedly warned in _The Waste Products of Agriculture_ that
if the underlying fundamentals of his process were altered, superior
results would not occur. That was his viewpoint in 1931. However,
humans being what we are, it does not seem possible for good
technology to be broadcast without each user trying to improve and
adapt it to their own situation and understanding. By 1940, the term
"lndore compost" had become a generic term for any kind of compost
made in a heap without the use of chemicals, much as "Rototiller"
has come to mean any motor-driven rotarytiller.
Howard's 1931 concerns were correct--almost all alterations of the
original Indore system lessened its value--but Howard of 1941 did
not resist this dilutive trend because in an era of chemical farming
any compost was better than no compost, any return of humus better
than none.
Still, I think it is useful to go back to the Indore research farm
of the 1920s and to study closely how Albert Howard once made the
world's finest compost, and to encounter this great man's thoughts
before he became a crusading ideologue, dead set against any use of
agricultural chemicals. A great many valuable lessons are still
contained in _The Waste Products of Agriculture. _Unfortunately,
even though many organic gardeners are familiar with the later works
of Sir Albert Howard the reformer, Albert Howard the scientist and
researcher, who wrote this book, is virtually unknown today.
At Indore, all available vegetable material was composted, including
manure and bedding straw from the cattle shed, unconsumed crop
residues, fallen leaves and other forest wastes, weeds, and green
manures grown specifically for compost making. All of the urine from
the cattle shed-in the form of urine earth--and all wood ashes from
any source on the farm were also included. Being in the tropics,
compost making went on year-round. Of the result, Howard stated that
"The product is a finely divided leafmould, of high nitrifying
power, ready for immediate use [without temporarily inhibiting plant
growth]. The fine state of division enables the compost to be
rapidly incorporated and to exert its maximum influence on a very
large area of the internal surface of the soil."
Howard stressed that for the Indore method to work reliably the
carbon to nitrogen ratio of the material going into the heap must
always be in the same range. Every time a heap was built the same
assortment of crop wastes were mixed with the same quantities of
fresh manure and urine earth. As with my bread-baking analogy,
Howard insured repeatability of ingredients.
Any hard, woody materials--Howard called them "refractory"--must be
thoroughly broken up before composting, otherwise the fermentation
would not be vigorous, rapid, and uniform throughout the process.
This mechanical softening up was cleverly accomplished without power
equipment by spreading tough crop wastes like cereal straw or pigeon
pea and cotton stalks out over the farm roads, allowing cartwheels,
the oxens' hooves, and foot traffic to break them up.
Decomposition must be rapid and aerobic, but not too aerobic. And
not too hot. Quite intentionally, Indore compost piles were not
allowed to reach the highest temperatures that are possible. During
the first heating cycle, peak temperatures were about 140 degree.
After two weeks, when the first turn was made, temperatures had
dropped to about 125 degree, and gradually declined from there.
Howard cleverly restricted the air supply and thermal mass so as to
"bank the fires" of decomposition. This moderation was his key to
preventing loss of nitrogen. Provisions were made to water the heaps
as necessary, to turn them several times, and to use a novel system
of mass inoculation with the proper fungi and bacteria. I'll shortly
discuss each of these subjects in detail. Howard was pleased that
there was no need to accept nitrogen loss at any stage and that the
reverse should happen. Once the C/N had dropped sufficiently, the
material was promptly incorporated into the soil where nitrate
nitrogen will be best preserved. But the soil is not capable of
doing two jobs at once. It can't digest crude organic matter and
simultaneously nitrify humus. So compost must be finished and
completely ripe when it was tilled in so that:
". . . there must be no serious competition between the last stages
of decay of the compost and the work of the soil in growing the
crop. This is accomplished by carrying the manufacture of humus up
to the point when nitrification is about to begin. In this way the
Chinese principle of dividing the growing of a crop into two
separate processes--(1) the preparation of the food materials
outside the field, and (2) the actual growing of the crop-can be
introduced into general agricultural practice."
And because he actually lived on a farm, Howard especially
emphasized that composting must be sanitary and odorless and that
flies must not be allowed to breed in the compost or around the work
cattle. Country life can be quite idyllic--without flies.
The Indore Compost Factory
At Indore, Howard built a covered, open-sided, compost-making
factory that sheltered shallow pits, each 30 feet long by 14 feet
wide by 2 feet deep with sloping sides. The pits were sufficiently
spaced to allow loaded carts to have access to all sides of any of
them and a system of pipes brought water near every one. The
materials to be composted were all stored adjacent to the factory.
Howard's work oxen were conveniently housed in the next building.
Soil and Urine Earth
Howard had been raised on an English farm and from childhood he had
learned the ways of work animals and how to make them comfortable.
So, for the ease of their feet, the cattle shed and its attached,
roofed loafing pen had earth floors. All soil removed from the
silage pits, dusty sweepings from the threshing floors, and silt
from the irrigation ditches were stored near the cattle shed and
used to absorb urine from the work cattle. This soil was spread
about six inches deep in the cattle stalls and loafing pen. About
three times a year it was scraped up and replaced with fresh soil,
the urine-saturated earth then was dried and stored in a special
covered enclosure to be used for making compost.
The presence of this soil in the heap was essential. First, the
black soil of Indore was well-supplied with calcium, magnesium, and
other plant nutrients. These basic elements prevented the heaps from
becoming overly acid. Additionally, the clay in the soil was
uniquely incorporated into the heap so that it coated everything.
Clay has a strong ability to absorb ammonia, preventing nitrogen
loss. A clay coating also holds moisture. Without soil, "an even and
vigorous mycelial growth is never quickly obtained." Howard said
"the fungi are the storm troops of the composting process, and must
be furnished with all the armament they need."
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