THE KEYLINE
SYSTEM HAS CHANGED ONLY SLIGHTLY FROM THE ORIGINAL BOOKS BY P.A.
YEOMANS. THIS EXPLAINS CURRENT THINKING.
http://www..yeomansconcepts.com.au/basis-of-keyline3.htm
Keyline planning
is based on the natural topography of the land. It uses the form and
shape of the land to determine the layout and position of farm dams,
irrigation areas, roads, fences, farm buildings and tree
lines.
Keyline
topographical concepts are often taught in university town planning
courses.
Keyline is an
agricultural system in which great emphasis is placed on processes
designed to increase substantially the fertility of soils. Emphasis is
placed on the creation of a soil environment that rapidly accelerates
soil biological activity, thus vastly increasing the total organic
matter content within the soil.
Keyline lay-outs
of farm and grazing lands also incorporate designs permitting the
storage of run-off water on the farm itself. This effectively spreads
the often irregular rainfall patterns so common to Australia, and in
consequence enhances rural production.
Keyline lay-outs
and practices are designed and predicated to the concept that farming
systems that improve the fertility of soils, and food production from
these soils, must be profitable to the man who farms the
land.
Keyline concepts
are totally against the current artificial and dangerous practice of
concentrating run off water into manufactured disposal drains designed
to remove, as rapidly as possible, run-off water off a rural
landscape. The rapid evacuation of rainwater to the nearest ocean, in
this, the driest of the world's continents is particularly illogical.
In addition, this practice can and often does create more disastrous
erosion than it was ever expected to cure.
Keyline considers
as totally erroneous the belief that soil creation is an infinitely
slow process and soil once "lost" is lost forever. In fact
soil fertility, and even soil itself can often be created faster than
it can be eroded.
Keyline practices,
once implemented, effectively eliminate soil erosion, even as a
possibility. The battle against soil erosion and the concept of
"soil conservation" as a significant issue becomes totally
meaningless.
The name Keyline
was given to the particular contour that runs through the point, in
all small headwater valleys where the slope change occurs. This
contour is the primary contour in Keyline planning. Among other things
it delineates the transition contour for cultivation, above which all
"contour" cultivation must proceed up the slope, and below
which all "contour" cultivation must proceed down the
slope.
The result of such
"Keyline Pattern" cultivation is that an overall drift of
surface runoff water occurs which prevents runoff concentration and
the resultant gutter erosion from occurring. It increases the time of
contact between the rain and the earth. It has the effect of turning
storms into steady soaking rain.
The Keyline
contour need not be on the individual farm. It is only necessary to
know whether the contour to be paralleled is above, or below a
relevant Keyline. In this way "drift" in either direction
can be determined and implemented. Paralleling up, or paralleling down
from a contour can direct the drift of rainwater away from erosion
sensitive valley floors.
The inversion of
soil layers is quite contrary to Keyline concepts and in fact contrary
to almost every type of soil fertility building practices anywhere in
the world. All cultivation, in fertility enhancing agriculture is best
done using an adaptation of the "forked stick" plough of
ancient times. Our own original cultivation experiments used a variety
of earth moving rippers until we discovered the Texas built Graham
Hoehme Chisel Plow. We redesigned the old Graham Hoehme Chisel Plow to
suit the more extreme conditions usually found in Australia. The
plough was developed and promoted. The acceptance and almost universal
adoption of chisel ploughs has been one of the most beneficial and
noticeable changes in Australian agriculture this last
century.
We found over time
that the chisel plow required more fundamental refinements. It was
good but it was still not the ideal implement for rapid soil
development type agriculture. It was virtually incapable of one-go
deep tillage without excessive soil profile disturbance. The current
Yeomans Plow thus evolved. And the modern subsoil plough was born.
These implements achieve virtually the ultimate in Keyline cultivation
requirements. They are able to operate well into the subsoil without
the usual, dilution by mixing, of the shallow topsoil with the huge
bulk of infertile subsoil underlaying it. The concept of the narrow
tine subsoiler we developed is now receiving wide spread acceptance by
both farmers and other manufactures.
This new plough
has allowed for much accelerated Keyline soil development progression
by eliminating the need for the time consuming, yearly increase in
cultivating depth necessary with the chisel plow
Keyline layouts
for rainwater collection, storage and irrigation has many advocates
especially following the experiments on Keyline techniques by Sydney
University and promoted as "water harvesting". The
universities lack in not also realising the importance of fertile
soil, as a most economical water storage medium, limited the worth of
their studies, and to some extent also restricted its
acceptance.
The refinement of
Keyline techniques following P.A. Yeomans' the original books has seen
a greater emphasis on determining the most economical planning
sequences for larger water storage sites, and even more rapid
fertility build ups. Larger farm dams have tended to prove more
viable.
A development
program and layout for a property, with a sequence of operations based
on relative economic viability of the individual stages, and including
the location of tree lines, road ways, water storage dams, fence lines
and houses is now easy and so totally logical. It is now a simple
matter to determine a complete farm or property design, often in a
matter of a few hours
While Keyline
designs are based on the topography and geology of the land,
individual properties, unfortunately, are shaped by an historic
location of survey lines, and such lines generally bear no
relationship whatsoever to topographical land forms. In consequence
idealised Keyline systems are usually hampered a little by the
restraints of farm boundaries. A major requirement of Keyline designs
is then to utilise the landform and topography, within the restraints
imposed by these boundaries. But that's easy.
Co-operation
between farmers to their mutual benefit would eliminate these design
restraints and make for huge economic savings and create viability for
water harvesting and storage systems that otherwise, just possibly,
could not exist. This coupled with correct cultivation and soil
development techniques to enhance biological activity would more
rapidly, vastly increase the fertility of all our soils, to all our
benefit.
The
following information is taken from:
PRIORITY
ONE Together We
Can Beat Global Warming by Allan J. Yeomans 2005
Keyline planning
is based on the natural topography of the land and its rainfall. It
uses the form and shape of the land to determine a farm 's total
layout. The topography of the land, when viewed in the light of
Keyline concepts, clearly delineates the logical position of on-farm
dams, irrigation areas,roads,fences and farm buildings. It also
determines the location of tree belts to provide shade and give wind
protection. Keyline concepts also include processes for rapid soil
enrichment. The shape of a landscape is produced by the weathering of
geological formations over millennia. The processes are always the
same.
And so the
topography of agricultural land has a basic fundamental consistency.
It is the inevitable nature of land shape that river valleys collect
water from smaller creek valleys. They in turn are fed their water
from still smaller valleys, until finally the water derives from the
very first, or primary valleys of the catchment area. In any
country,anywhere,when rain shapes the land over long periods of time,
it inevitably creates and determines the topography of that land.
Ultimately, at the extreme upstream of any river system there always
exists thousands of primary valleys. The only variation to consistent
topographical shapes occurs where geological features, such as hard
rock outcrops modify normal surface weathering.
At the end
of all these branches, sub-branches an sub-sub branches are thousand
of even smaller valleys that are the primary valleys so important in
Keyline planning. The map is of northeast New South Wales and
southeast Queensland and shows part of the catchment areas of the east
Australian inland rivers system.
A contour is a
line meandering over the ground, always at the same height above sea
level.The name Keyline was given to a single, very unique contour that
occurs in all primary valleys. As you walk up the watercourse in a
primary valley, the slope of the valley floor will suddenly increase.
That point of sudden steepening is the "Keypoint " of the valley.
A contour line surveyed to run through this Keypoint becomes the
Keyline contour for that valley. Because of the consistency in
water-formed topographical land shapes there is always a
Keyline.
The Keyline is
always the primary contour and guideline that tells us which way to
cultivate when attempting contour cultivation. It is also a logical
starting point for any farm layout planning,and supplies a fundamental
principle on which modifications to existing layouts can be based. In
planning the layout of a farm or ranch it is often the case that no
other contour lines on the property need be surveyed and pegged, just
the Keylines for each primary valley. Keyline contour surveying
expenses therefore are always minimal. Normally when any conventional
contour ploughing is undertaken,a contour line is first pegged or
otherwise marked on the ground, then ploughing commenced.
Cultivation runs
are made somewhere between the valley centre line and the adjacent
ridge. The first furrow is ploughed adjacent to, and parallel to the
marked contour line. The second run is of course adjacent to the first
and so on. Let 's say, for illustration that each run is ploughed
below the previous run, as in the diagram on page 134. Because of the
natural topography of rain formed land shapes,cultivation runs soon
and inevitably depart from the original and accurately marked contour.
This always happens and usually after only a few parallel
runs.
This
diagram indicates the terms used in describing Keyline concepts.
Contour intervals are drawn in from the 130-foot line to the 260-foot
line.
In conventional
contour cultivation this effect is never appreciated and, more often
than not, is seen as an apparently unexplainable irritation. Or it 's
ignored and invariably to the detriment of the land. Because of this
off-contour drift, water flow can be directed the wrong way and
contour cultivation then creates the very erosion problems it is
supposed to solve.
Keyline
cultivation centres on the planned and logical use of this
"off-contour " cultivation and water drift phenomenon. In the
illustration the length of the guide contour shown might be a few
hundred yards long and the picture represents an area on the side of a
primary valley. The slope of the land surface is always a little
steeper at one end of this line than at the other end.
This difference is
important in understanding Keyline cultivation. In the illustration,
when ploughing by paralleling the guide contour and then progressively
progressing down the slope, each successive cultivation run will be
slightly lower at the steeper end of the paddock. This follows as each
pass with the cultivator will always have the same width, but across
each width the vertical height will be slightly
different.
Inevitably, after
just a few passes, the ploughed furrows will no longer be on a true
contour. They will now have a defininite fall one-way or the other, in
this case to the left. Rain run-off will therefore tend to have a
positive flow, or drift along the now slightly descending
furrows.
Now, if on the
other hand the ploughing starts parallel to the true contour but this
time ploughing progresses up the slope, then each successive
cultivation run will be slightly higher at the steeper end of the
cultivation area. Again the individual cultivation runs will no longer
be true contours. The drift of rain or irrigation water run-off will
be reversed. The water will move to the right. It 's logical to delay
the concentration and velocity of rainwater wherever possible so it
makes sense to give water a bias to move out form the valley centre
and not into it. Such drifts dramatically minimize the all too common
rapid concentration of rainwater in valleys.
The hundreds of
furrows in Keyline pattern cultivation spread the water and inhibit
concentrations. In total contrast the contour banks or drains
advocated by standard soil conservation practices are designed to
rapidly concentrate water into a valley, which naturally increases its
eroding action. Understanding this fundamental concept gives us
control of rainwater drift and ?ow over the land surface. Of course if
an area, for some extraneous reason is always too wet, reversing the
sequence of cultivation will dry it out. The Keyline contour is
extremely important in contour cultivation. Above this unique contour
the valley is steeper than the adjoining ridge. Below
Illustrating how cultivating parallel to a contour
line inevitably forces succeeding ploughed furors away from being true
contours.
the Keyline the
valley is matter than the adjacent ridge. Thus cultivating parallel to
the Keyline contour and moving up the slope drifts water out of the
valley and cultivating parallel to the Keyline contour and moving down
the slope also drifts water out of the valley. If this phenomenon is
not recognized, what is supposedly contour cultivation can manufacture
the erosion that contour cultivation is traditionally believed to
prevent. This subtle but critical feature occurring in all natural
landforms determines surface water movement and this must be
appreciated before attempting contour ploughing.
The Keyline
contour is thus the "transition " contour. Above the Keyline,
contour cultivation runs must progress up the slope. Below the
Keyline, contour cultivation runs must progress down the slope. The
result of such Keyline Pattern cultivation is that the overall drift
of surface run- off water tends to always drift run-off away from the
wet valley floor and out onto the dryer ridge. Erosion caused by
rainwater flow is effectively eliminated. Normally most water erosion
occurs down the centre line of a valley and results from
The solid
lines are true contours. The dashed lines depict parallel cultivation
furors.
The diagram
above left shows a primary valley and its Keypoint along with its
associated Keyline.
Cultivation
has proceeded from the Keyline up the slope and also from the Keyline
down the slope. Both drift the run-off rainwater away from the valley
floor. Above the Keyline cultivation must always start at a true
contour and parallel up the slope. Below the Keyline cultivation must
always start at a true contour and parallel down the slope. In other
words all cultivation runs must always parallel away from the valley's
Keyline.
In the
diagram above right the upper cultivation is correct and is proceeding
away from the Keyline. But note how in the lower cultivation area the
runs are starting at the 130-foot contour and proceeding towards the
Keyline thus forcing runoff to concentrate into the valley
centre.
the excess concentration in water volume and water speed that normally
occur there. Keyline pattern cultivation spreads the ?ow out over a
wide area, rendering it harmless. It also markedly increases the time
of contact between the rainwater and the soil. Water has more time to
be absorbed. Keyline pattern cultivation has the effect of allowing
heavy storm rains to be absorbed more easily into the earth. Generally
such absorption only ever happens with steady soaking
rain.
Keylines in
adjacent primary valleys are always slightly lower as you proceed down
the main valley or watercourse linking the primary valleys. The
location of farm dams or ponds are decided by using that valley 's
Keyline to determine the highest water level for the proposed
dam.
A Keyline contour
drain can then collect any run-off and help ?ll the dam. Because of
the drop in height of successive Keylines, an outlet pipe through a
dam wall will generally approximate the level of the Keyline in the
next valley downstream.
Generally, with
very minor adjustments in levels, dam sites can be logically linked so
each Keyline dam can feed, via a contour channel, to the next lower
dam. These contour drains are can be the same as conventional soil
conservation drains but must be almost ?at to prevent the erosion soil
conservation drains can cause. A fall of 1 in 500 or even 1 in 1, 000
is usually plenty. Installing a big outlet pipe is wise when
constructing a farm dam as this gives absolute control of the system
and pumping becomes unnecessary. Everything is done by gravity. The
design of farm dams, constructed with large irrigation pipes a foot or
more in diameter, buried under the dam wall and fitted with valves,
and farm dams that can be filled or emptied by contour drains, is a
Keyline concept.
It is a concept my
father borrowed from his experience in gold mining and gold washing in
Australia and New Guinea. In gold mining, water often has to be
transported for miles, usually through diffcult country and it must be
done cheaply. In gold mining, even more so than in farming, water
itself is gold. Water's collection, storage and cost are of critical
importance. The placement of dams with their feeder and delivery
channels
\
An
irrigation drain with two ?ags in position in readiness to hold back
and over flow the water stream
Canvas wall
being used to ?ood irrigate hill side land after previous Keyline
pattern cultivation. The water, released by the valve in the back of
the dam wall, moving along the drain under gravity has reached the
?rst ?ag, ?lled it, and just commenced to ?ow over the lip of the
drain to irrigate the land below. The fence in the picture is
constructed to form the upper limit of the irrigation paddock.
P.A.Yeomans demonstrates his system.
determined by the
relevant Keyline contour is the logical adaptation of old mining water
handling techniques to agriculture. I once found an old contour earth
drain, miles long, in the hills near the town of San Andreas in
California. It must have been hand built by some of the
"forty-niners "to wash gold from their claim.
To me it looked
exactly like a Keyline drain on my father 's farms. As sometimes can
happen, storm rains occur when farm dams are already full. But that 's
O. K. as the Keyline cultivation patterns in the valleys effectively
spread the width of the moving floodwater and so decrease its
velocity. The valleys become covered with a wide sheet of slowly
moving water. Even in steep country the land won't erode. Keyline 's
cheap efficient dam construction and water transport systems mean that
increasing grass and crop production by irrigating from the on-farm
water storage ponds can vastly accelerate soil fertility development.
To irrigate using the Keyline systems the pipe through the dam wall is
turned on, flooding the Keyline channel to the next dam. This channel
can then be blocked with a pegged down sheet of canvas (called a
"?ag ")forcing the water to over flow the channel and good down the
slope.
Aerial
photo of the trees on Nevallan.Using Keyline design principals either
land is cleared, or on cleared land trees are planted, to form both
windbreaks and shaded areas for livestock. Trees are ultimately
harvested and the tree belts replanted.
The patterned
cultivation spreads the water with ample consistency. The canvas wall
is then moved further along the feeder channel to a new location and
the process is repeated. Each move takes just a few minutes. In very
?at land a slightly different system is used. Either way a person can
comfortably irrigate and control water flow rates easily exceeding one
acre-foot per hour (one mega litre per hour). The per-acre cost of
irrigation equates to simply interest cost on the capital to create
the dams and the contour channels, plus the few minutes required for
each move.
There is no
cheaper form of irrigation. Keyline principles are totally against the
concept of concentrating run-off water into manufactured disposal
drains that are specifically designed to remove rainwater off the farm
as rapidly as possible. Yet the supposedly safe rapid removal of water
off a farm is the basis of all current soil conservation
principles.
In Australia, the
driest of the world 's continents, such advocacy is almost criminal.
Using Keyline design principals either land is cleared, or on cleared
land trees are planted, to form both windbreaks and shaded areas for
livestock. Trees are ultimately harvested and the tree belts
replanted. The other major facet of the Keyline system involves the
soil itself.
Keyline uses
concepts of rapid and economical soil fertility
enhancement.
As Keyline
developed it became obvious that rapid increases in soil fertility
from the substantial increase in soil biological activity, could and
should be an underlying fundamental of all farming endeavours. The
soil in Keyline philosophy is never cultivated by turning the earth
upside down.
Cultivation is
only undertaken using modern versions of the forked stick of ancient
agricultural practices. The Graham Chisel Plow was used for years for
Keyline soil development until we developed, in the 1970s an efficient
and practical implement, capable of effective subsoiling as well as
filling the role of a chisel plow. This implement reached deeper into
the soil than a chisel plough but with considerable less soil pro ble
disturbance.
The resulting
improvement in soil fertility, with either implement not only
increases crop yields and food production, but also simultaneously
reduces costs.
Additionally, less
water is required if irrigation. For more on subsoiling
see
EXTRA:THE FORKED STICK AND THE SUBSOIL PLOUGH in PRIORITY ONE Chapter
8.
Soil is
never homogeneous even if it appears so. In any soil, individual bits
randomly clump together and form crumbs or aggregates. The better the
soil, the greater the quantity and mass of aggregates within the soil.
The bits in the aggregates tend to hold together much more tightly
than the assembled aggregates hold to each other. The degree of
aggregation de fines "soil structure ".
Soil aggregates
however, can easily be broken up and destroyed by tumbling in a cement
mixer. Either wet or dry, the aggregates break up. Excessive soil
cultivation has the same effect. Land is sometimes cultivated several
times to produce a "fine seed bed "in which to sow. This is a
mistake. It is a harmful practice and is being abandoned. Edible crop
seeds germinate within soils when humidity levels are high and air is
available, not in water saturated soil.
However, in any
crop preparation prior to planting, at least one cultivation is
required, both to loosen compacted soil and act as a weed killing
operation. The much-publicized arguments promoting the concept of
"minimum tillage "is primarily an argument that the weed killing
cultivation should be abandoned and herbicides be used to control
weeds. In the so-called "zero tillage "concept, crops are
supposedly to be grown using only seed and chemicals.
Many farmers have
tried zero tillage but found (as one might expect)it doesn 't work.
The shape and the size of the aggregates in soil vary considerably.
They are typically the size of very small pebbles. The spaces between
the aggregates (called pores)can fill up with air and water. If the
aggregates hold together well and resist crushing, and have a good
general shape so that the pores form nice little connecting channels,
then the soil is said to have a good "structure ".
The tiny ?brous
roots of plants and grasses love to meander down through the maze of
passages in a well-structured soil, hunting for nutrients. All those
little pores and channels have the ability to hold water. The volume
held is termed the "field capacity ". Field capacity is designed
as the measure of a soil 's capacity to retain water for plant use.
Retention is a critical factor so field capacity is usually considered
as the volume of water retained in the soil a couple of days after
heavy soaking rain. It is what is retained after excess water has had
time to drain away. Field capacity determines how long soil life can
function and operate efficiently before another rain shower becomes
essential. Rich, humus-laden soil has excellent field capacity. Poor
soil has very little. Sand has almost none.
Organic farming
and Keyline farming practices massively increase yield capacity,
thereby decreasing rainfall and irrigation requirements. To initiate
the soil building process in Keyline (and in any natural fertility
enhancing process), it is first necessary to grow a "crop "of
almost any form of vegetation. That crop dies, drops litter, or sheds
root matter, which in turn decomposes to become soil organic matter
and ultimately stable humic acid. The crop need not necessarily have
accepted commercial value. It only needs to be voluminous and readily
decomposable. The use of limited quantities of chemical fertilizers,
such as lime or superphosphate, to stimulate the volume or mass of
that initial crop is, unlike strict organic farming mandates,
perfectly acceptable in Keyline development, but only in the first
year.
After that,
chemical fertilizers must be avoided to ensure a rapid increase in
active soil life. It is acknowledged that efficient biological soil
development processes are impossible with continuing high chemical
use. If not constituting the first crop, then grasses and legumes
should be utilized in the second growth phase. This second crop has
definite commercial value. It can be eaten off periodically, or it can
be regularly forage harvested. Keyline concepts beginning in the early
1950s have consistently advocated the overstocking of con ?ned grazing
areas for short periods such as a few days, then moving the stock
animals onto a new area to produce a constantly decomposing mass of
root matter.
This procedure is
discussed in Chapter 8: HOW WE CREATE FERTILE SOIL TO STOP GLOBAL
WARMING . This
same procedure has just recently been adopted and promoted as "cell
grazing " or "rotational grazing "by the new "holistic "
agricultural consultants. Cell grazing concepts however, form only
part of the broader concepts of soil fertility enhancement.
T
he development and
enrichment of fertile soil are processes that have been known for
centuries. Keyline soil enrichment systems merely streamline the
process. Organic farmers are usually familiar with the general
techniques. In Keyline the soil building process is accelerated by
subsoiling with an implement that guarantees minimum soil layer
disturbance. This is then coupled with rotational grazing and,
ideally, with low cost irrigation. The objective in Keyline is to
always make the creation of healthy fertile soil a profitable
endeavour for the farmer. There are several facets of Keyline. Over
the years since its inception many have been adopted singularly and
have proved profitable even in isolation. Farmers have adopted Keyline
layouts for rainwater collection, storage, and
irrigation,
A Graham Plow
especially built for a Queensland farmer. It was 69 feet wide,and
believed to be the largest plow in the world at the time (1955). (from
THE CHALLENGE OF LANDSCAPE .P,A. Yeomans 1958.)
especially
following the successful trials on Keyline techniques by Sydney
University at their McGarvie Smith Animal Husbandry experimental farm
at Badgery 's Creek NSW in the 1960s. The University very successfully
promoted the Keyline concepts as a form of "water harvesting ".
Although Badgery 's Creek is in the same county as Yobarnie and
Nevallan, the soil types are not absolutely identical, but the
University found the bene ?ts indeed were. Here in Australia I am
often asked, "Have Keyline concepts been taken up by many
farmers?". Yes they have. Over the last fifty years I have seen
Australian agriculture change dramatically. Many of the facets of
Keyline have now become "conventional "agriculture in this
country.
We see
Keyline concepts and philosophies adopted everywhere. We see it in the
establishment of tree belts, the design and location of farm dams, the
general use of contour drains, not to supposedly prevent erosion, but
to convey water to and from farm dams and to good irrigate from these
drains. We see it in the widespread adoption of non- inversion tillage
practices with the widespread use of chisel ploughs and the heaver
subsoiling ploughs developed from them. We also see farmers minimizing
or often eliminating their use and reliance on agricultural
chemicals.
This change has
come despite considerable resistance by the Australian soil
conservation establishment to most of the concepts of Keyline
thinking. It is a marketing reality that big money talks. In
consequence, and by a variety of means, government agencies everywhere
are coerced by the agrochemical companies into listening to and
accepting almost as gospel, the promotional material the companies
produce. Most governments now accept the fabricated concept that bene
?cial agriculture totally relies on and is dependent on, high chemical
inputs. Such indoctrination unfortunately prevents both the enrichment
of the world 's soils and the entrapment of carbon dioxide into them.
In addition to their use in agriculture, Keyline topographical
concepts have been included in several university architectural and
town planning courses in Australia, the concept being that the layout
of large-scale subdivisions and even whole towns could be planned
based on the concepts.
Keyline concepts
and designs are becoming increasingly widespread as time goes by.
Professor Stuart B. Hill, Ph. D. , who holds the Foundation Chair of
Social Ecology at the University of Western Sydney, and Martin
Mulligan, a lecturer in that faculty, and who is also editor of the
journal Ecopolitics:Thoughts and Action, recently co-wrote an
excellent Australian historical book Ecological Pioneers
.
In
discussing my father and the concepts involved in Keyline designs,
they say:- "Despite its marginalisation by conventional
agriculturists, Yeomans ' approach to ecological design was, as
mentioned above, one of the main sources of inspiration for the
development of "Permaculture ". The birth of this movement dates
back to 1972 when Bill Mollison -a psychology lecturer and
well-known "identity "at the University of Tasmania, and David
Holmgren -a student in the Environmental Design Course at the
College of Advanced Education in Hobart, began an unlikely but highly
productive collaboration.
The
extroverted Mollison has gone on to establish an international
reputation as the "father "of Permaculture; giving inadequate
credit to Holmgren and virtually none at all to Yeomans.(wes
says-Not True=Bill M. always gave great credit to PA Yeoman at all PDC
courses over the years) Holmgren 's story is certainly less
well known, but of great importance in tracing the lineage of ideas
that have manifested themselves in Permaculture design practices.
"
Keyline practices,
once implemented, effectively eliminate all soil erosion. The
"battle against soil erosion ", the concept of "soil conservation
", and the costly bureaucratic industry these buzzwords have
created, become irrelevant and unnecessary.
Keyline, like
classic organic farming, is a soil creation system. It is not a soil
conservation system at all. Soil conservation is a negative term and
implies merely delaying some inevitable future situation where
apparently all the World 's soil will be gone.
The Keyline system
as originally conceived was not designed to produce organic food, nor
was it designed to assist the mitigation of Global Warming. It was
designed to develop poor land into good land, and it was designed to
make farming pro ?table in the quickest most efficient
way.
To me, Keyline
became important in relation to Global Warming and organic farming
because it was a tenet of Keyline philosophy that the best path to
achieve its objectives was via the creation of highly fertile soil.
And fertile soil is humus-rich soil, and forming humus consumes huge
quantities of carbon dioxide. Although Keyline concepts were never
designed with the prevention of Global Warming in mind, I believe that
the widespread adoption of Keyline principles is probably the most
practical and profitable change that agriculture should embrace to
achieve that worldwide imperative.