Keyline Farming 1955 from RegenAG on Vimeo.
The following links can be sourced for consultation and training in Keyline methods.
http://www.permaculture.biz/
http://www.yeomansplow.com.au/basis-of-keyline.htm
http://www.yeomansplow.com.au/yeomans-plows.htm
http://milkwoodpermaculture.com.au/courses/details/19-milkwood-spring-kfw?gclid=CI6l4_nmiKMCFRAZewoduTCGeg
KEYLINE PLANNING PRIORITIES.
The development of living soil can be done most economically in a landscape, that is specifically designed to achieve these results. The Keyline Scale of Permanence provides a priority guide to planning the various factors considered in the design of the landscape. In this scale the utilisation of the water resources of the landscape is designed after considering the climate and topography (land shape). Then the location of roads, trees, buildings and fences may be logically planned in this order.
The Keyline design is unique to each property so the plan is always custom made to the property. Thus Keyline reveals the potential and develops the uniqueness of the property. The design process often reveals unsuspected potential and dispels illusions. Experience is necessary to reveal the full potential of any property. Design is done both in the office and in the field. The initial office work speeds the assessment and uses the information derived from detailed contour maps of the area. On the basis of the initial assessment, key points within the apparent design potential of the property are selected. The vertical relationship of the features of the landscape can then be established. Preliminary plans and designs can be formulated. The practical design work starts from the key points and revealed relationships. During the initial on site survey of a property, contour or grade lines are pegged, as required, from the key points previously selected. Dam sites may be chosen, pegged, volume estimates made and the best irrigation areas delineated. This work is best done on site and usually the first stage or starting project of the plan is laid out on the land.
The hallmarks on the properties of successful Keyline farmers are lakes with water birds, contour and ridge line roads and contoured and strip forests, dark fertile soil, luxuriant healthy green crops and feed. Well-designed landscapes can be beautiful and highly productive. Keyline techniques increase profits by increasing soil fertility, improving farm water utilisation, reducing production costs and increasing productivity.
One of the primary objectives of Keyline planning is to enhance the swift development of deep biologically fertile (living) soil in a designed landscape systematically planned for permanence. Keyline methods rapidly develop the biological fertility and structural stability of the soil and reduce water loss from the land. Keyline is the natural way to defeat the menace of soil erosion and salinity, simply as an incidental to total landscape betterment.
The Keyline Plan is to prepare the land to quickly absorb, and hold by way of increased field capacity, increasing amounts of rainfall, and to store surplus run off water, where ever practical, in large, on farm storages each equipped with a 'Lockpipe System'. The Lockpipe System is a large pipeline positioned under the dam wall, which when opened, releases the water rapidly for use by gravity powered irrigation. Keyline irrigation is quick, not labour intensive and functions to enhance the development of deep, living, fertile soil.
AERATION AND WATER ADSORPTION
Keyline uses cultivation, irrigation and stock management techniques to greatly speed up the natural process of living soil formation. Conversion of subsoil into top soil may, under natural conditions, occur at 10 to 15 tonnes per hectare each year. On Keyline farms, during the conversion process, this figure may increase beyond 10 to 15 hundred tonnes per hectare each year. The numbers may be surprising but annually deepening the topsoil by 10 to 15 cm (ie 4 to 6 inches) achieves this result. It is a practical short term goal to deepen the living top soil to 30 and 45 cm (twelve to eighteen inches).
Changing the subsoil conditions to better suit aerobic soil organisms enables the conversion of sub-soil into topsoil. These organisms need warmth, space for air and moisture plus a plentiful supply of high protein food.
Loosening the soil and applying dung is a long standing method to improve agricultural production (see Luke 13:8). Various tools can loosen the soil and provide additional space for plant root expansion, air and moisture in the soil. Plant roots and organisms easily grow and multiply into this space. To loosen the soil on a farm, use equipment that does not invert the soil. Improving the living conditions for soil organisms also requires a food source for them. An exceptional high protein food source is the root systems of pasture legumes, but this food supply is not available during plant growth. For rapid soil development some of the roots must die! Use stock to quickly eat down most of the above ground parts of the plant. Mowing is a poor substitute because it lacks the return of manure to the soil. The presence of animal manure can also greatly increase the growth rate and size of earth worms.
The best time for eating down pasture is when the selected plants are preparing to flower and set seed. At this stage of growth, the root systems are at or near maximum size. The larger root systems provide a better supply of accumulated energy for the plant to recover from being eaten and more roots to decay and provide feed for the soil organisms. The plants' energy and nutrient reserves were for seed production. Eating down was a shock but the plants recover to try again. Following the eating down, and especially in conditions of warm, moist loosened soil, re-growth will be fast and replacement roots develop as the plant re-grows. Stock must be moved on, to another area, to prevent them from eating the early regrowth. During this regrowth phase inspect the soil with a spade. The new roots look white compared to the darker, brownish, old and dying roots. The soil organisms eat the dead roots and produce humus. This is a process of recycling the raw organic matter of the dead plant roots and the dung. Repeating this cycle of growth and decay builds the soil's biological fertility.
The best time to loosen the soil is when the optimum combination of heat and moisture is immanent. Repeat the process annually for three years in combination with the other management techniques. When irrigation water is applied quickly to loosened soil it can speed up the building of living soil.
Soil loosening requires suitable agricultural equipment and P. A. Yeomans was the first to manufacture a chisel plow tough enough for Australian conditions. In the 1970 a new breakthrough came with the development of the Bunyip Slipper Imp with Shakaerator, a vibrating narrow tyned sub-soil loosening plow. This plow won the prestigious Prince Phillip Prize for Australian Design in 1974. Many patented new developments have been added to the plow by P. A. Yeomans' second son Allan J. Yeomans, who now produces the plow at his Yeomans Plow Company on the Gold Coast of Queensland. These plows deeply and efficiently loosen the ground. They need less power to loosen more soil and produce less surface disturbance than the old chisel plows they have replaced.
CONTROLLING SURFACE WATER MOVEMENTS.
Physically loosening the soil will leave some sort of pattern etched into the surface and this pattern will influence surface water movements. The direction that water will flow is always down the maximum slope and this is at right angles to the contours. However run-off water will tend to flow along any furrows left by cultivation that produces anything from 100 to 500 or more furrows per hectare depending on row spacing. The furrows influence the way surface and sub-surface water will drift across the landscape. The surface disturbance may be comparatively slight but it will still alter the direction of flowing water. Then ripping is made deep and into the subsoil it will sculpt a corrugated pattern of furrows into the undisturbed subsoil. Water trapped in the furrows can slowly move along them.
Contour cultivation is an attempt to create a pattern of furrows that are all parallel to the contour. The logic is that contour furrows trap the water and allow it to soak into the soil and this usually increases rainfall absorption. However, at a farm scale, true contour cultivation, on land with visible shape, is not possible. The reason being is simply that adjacent contour lines are not parallel to each other across the surface of the land. Contour lines are parallel vertically but the horizontal spacing varies according to the slope of the land. Any pair of contour lines will be further apart where the land is flatter than where the land is steeper. The result of this changing horizontal spacing of the contours causes cultivation, done parallel with one contour line, to become off the contour cultivation the further away it progresses from the initial contour guide line. What starts out as contour cultivation quickly develops into an 'off the contour' cultivation pattern. Run off water will flow down the furrows towards wherever they lead.
As a result of the Keyline land shape discoveries, the development of the furrow pattern is now predictable. One realisation was that working parallel on the top side of a contour will result in a pattern that moves water from the steeper slopes to the flatter areas. Working parallel on the lower side of a contour guide line will produce a pattern that moves the water toward the steeper areas from the flatter areas. Why is this? With cultivation done parallel on the top side of a near contour guide line, each pass across the area will have the equipment more quickly gaining height up the slope wherever the land is steeper than where the slope is more gradual. In a similar way cultivation done parallel on the lower side of a contour or near contour guide line, will lose height quicker in the steeper areas than on the flatter areas. Run off water will tend to flow along these furrows.
Although rainfall tends to distribute moisture evenly onto adjacent ridge and valley shapes, the water does not stay evenly distributed. Natural drainage removes the water from the ridges to the valleys very efficiently. As a consequence of this, ridges tend to be drier than valleys. Any compaction of the soil worsens the problem. The soil in the valleys does not necessarily benefit from this moisture. An imbalance of water and air can cause aerobic soil organisms to die out and be replaced by anaerobic organisms. The soil will then become sour. Tussocks and water weeds in valleys are indicative of this problem. It is important that this result is not treated as a problem of excess moisture to be drained away but as a symptom of water probably being squandered from the upper slopes. Solve the problem at the source.
Most people don't have any difficulty appreciating the undesirable imbalance between the moisture of valleys and ridges. Keyline pattern cultivation is a simple way to solve the problem. It is a farm cultivating pattern that keeps the water on ridges longer and spreads water whenever it reached the valleys.
Keyline pattern cultivated land looks like contour cultivated land, but it is more than it appears. The Keyline cultivation method produces an amplified contour pattern. The cultivated furrows loop higher through the valleys and sweep lower across adjacent ridges. This pattern of cultivation increases the moisture absorbed on the ridges and reduces the concentration of water in the valleys. The late P. A. Yeomans made highly significant conceptual breakthroughs to enabled him to discover how to theoretically achieve this incredible water spreading pattern. He was practical enough to turn it into a practical reality of international significance.
The corrugated furrows of Keyline cultivation form a pattern which direct run off water and sub-surface flows toward the ridges from higher points in adjacent valleys. When water eventually reaches and starts to flow in Keyline pattern cultivated valleys, it takes the form of a stream that is uncommonly wide and shallow. This wide shallow stream is far less destructive than that which normally forms. One Western Australian wheat grower claims Keyline pattern cultivation produces a 30% to 50% increase in yield compared to the conventional round and round the paddock cultivation method. The steeper country produced the greater increase. Astonished government officers confirmed the results.
The usual round and round the paddock cultivation method produces an undesirable pattern of furrows. These furrows concentrate surface flows into the bottoms of valley shapes and onto the diagonals leading to the lower corners of the paddocks (fields), often causing soil wash and erosion.
THE SIMPLE WATER SHAPES OF LAND.
THE MAIN RIDGE
In Keyline lingo, a 'main ridge' starts at the junction of two creeks. The centre of this ridge is the water divide line between the two adjacent creeks. This main ridge will eventually branch as it creates the water catchment area of each creek. The catchment area of any creek always follows a main ridge.
PRIMARY VALLEYS
Small valleys intrude into and drain the sides of the main ridge. These are 'primary valleys'. The relatively larger section of the main ridge that remains on either side of the each primary valley is a small ridge in its own right and is called a 'Primary ridge'. When several primary valleys join, without forming a creek, they form a 'secondary valley'. The ridge between secondary valleys is a 'secondary ridge'.
'Primary ridges' are relatively larger than 'primary valleys' and main ridges dominate the landscape.
HILLS AND SADDLES
High points along ridges are 'hills'. A 'saddle' occurs at the low point between hills, along any ridge line.
THE KEYLINE PATTERN OF CULTIVATION
Ridges have a pattern to their contours and valleys also have a pattern to their contours. By understanding the pattern we can then learn how to produce a Keyline water distributing pattern of cultivation on ridges and valleys. Keyline pattern cultivation is one of the keys to the regeneration of the landscape.
The centre line of a ridge is the water divide line. It is usually flatter than the land sloping away to each side of the ridge. The typical spacing of contour lines across a ridge is wide at the centre (water divide line) and closer together off to the sides. To produce the Keyline pattern of cultivation, where the land has a ridge shape pattern to its contours, plow parallel on the upper side of any contour, or near contour guide line.
Valleys are somewhat like upside down ridges in that the centre line slope is flatter than the sides. The drainage line down the centre line of valleys is flatter than the land rising up on the sides of the valleys. The spacing of any contour lines marked on the land, or on a map, will be wide down the centre of the valley and closer together up the sides. This is a typical valley pattern and where the land has a valley shape pattern to its contours the procedure to adopt is to cultivate parallel and on the lower side of any contour, or near contour guide line.
Primary valleys result from the intrusion of valley shapes into the sides of main ridges. The land above or perhaps we should say beyond, the limit of intrusion of the valley shape, is still main ridge and has a ridge pattern to its contours. This area may have a basin shape and the contours be concave but the contour pattern is that of a ridge. The normal valley pattern, namely having a flatter centre line than sides has never been formed in this area so the cultivation of this area, at the top of a valley, should be the same as for other ridge shaped land. Namely parallel upwards from a contour guide line. Cultivate the lower portions of a valley parallel downwards.
The Keyline of a primary valley is the highest contour cultivation guide line that will produce a water distributing pattern on the valley below it. The Keyline is also the contour line across the valley with the most exaggerated curve up into the valley. Cultivation parallel with it, will thus produce the desired off contour cultivation both above and below it as all other lines have less curvature. Cultivation done parallel on both sides of the Keyline, both up and down produces the desired water spreading pattern automatically.
A Keyline used as a cultivation guide is a valley feature. A Keyline does not extend out on to the adjacent primary ridges. It stops on either side of the valley where the contour line, selected as the Keyline, changes direction (the horizontal inflection point) from the concave curve of the valley to the convex curve of the ridge. A Keyline can not exist on a ridge shape.
(A confusing concept called a "common Keyline" was included in the 1954 book 'The Keyline Plan'. It referred to a method of subdivision of land where the Keylines of adjacent valleys happened to occur on a similar level. When this occurs channels, roads, trees and fencing could be linked across the landscape. The connecting line was called a common Keyline. This is common in the mutual sense not in the usual sense. Some have mistakenly considered that Keylines therefore can exist on ridges and could be used as a cultivation guide line for the land on the ridges below this line. The "common Keyline" idea was never written into subsequent publications but the publishers of the beige coloured edition called 'Water for Every Farm Using the Keyline Plan' carried a reprint of the original chapter and diagrams and unfortunately reintroduced this term.)
In choosing the location of a Keyline, the Keypoint is chosen first. From here one can peg the Keyline out in both directions from the selected Keypoint.
The cultivation done parallel to and above the Keyline, results in each pass with the equipment gaining height faster in the centre of the valley. This causes the development of a pattern that will drift any run off water out towards the more gradual slopes of the adjacent the ridges and away from the steep centre of the valley and the slopes above it.
The cultivation done parallel to and below the Keyline, results in each pass with the equipment losing height faster on the steeper sides of the valley. This causes the development of a pattern that will spread any run off water out from the flatter centre of the valley towards the steeper side slopes and the adjacent ridges.
The unique thing about a keyline from a cultivation point of view is:
1. The Keyline is it the lowest contour line that crosses the valley that can be used for parallel upwards cultivation of the head (upper reaches) of the valley area; and
2. The Keyline is also the highest practical contour that can be used as a guide for the valley cultivation below.
In both cases the cultivation pattern that will develop will tend to drift run off water away from the valley and out towards the ridges beside it.
Most of the landscape is ridge pattern. This being the case nearly all cultivation should be done parallel with and above any contour guide lines. This procedure will develop the Keyline pattern automatically in all areas except the lower portions of valleys where the cultivation should be done parallel to and on the lower side of any contour guide line.
KEYLINE IRRIGATION SYSTEMS.
Keyline Pattern Irrigation
Keyline Pattern Cultivation has made practical the low cost watering of undulating country and hillsides by the 'Keyline Pattern Irrigation' system.
Previously the only method of fully controlled flood irrigation of undulating country was by the use of terraces, such as are used to create rice paddies.
Keyline pattern irrigation uses irrigation flags to block the irrigation stream flowing along an excavated channel. The water overflows the lower lip of the channel onto the land below. Keyline pattern cultivation will keep this water on the ridges and prevent it being lost into the valleys. Keyline pattern cultivation transforms 'wild flood irrigation' into fully controlled Keyline pattern irrigation and enables the use of astonishingly large streams of water for rapid irrigation.
Keyline irrigation techniques are also applicable to flatter lands. In flatter country the storage ratios of farm dams are usually better, which means that more water can be stored in proportion to the earthworks in the dam walls.
In suitable flat country, the unique 'Keyline Contour Irrigation Channel' has enabled:
FloodFlo Irrigation
FloodFlo Irrigation may be the fastest, fully controlled, one man, gravity powered, irrigation system in the world. Raised banks of the channel keep the bulk of the water above the height of the natural surface. The water is released through special irrigation gates which enable irrigation flow rates of around 10 megalitres (8 acre feet) of water per hour to irrigate at the rate of 20 hectares (50 acres) per hour when applying about 55 mm (2¼ inches) of water. Inundation times during irrigation are preferably kept to less than half an hour. Traditional methods of slow flood irrigation used in most large scale irrigation schemes drown aerobic soil organisms, cause crop deterioration and promote salinity.
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