Landowners all around the world are seeking more sustainable, cost-effective ways to manage their properties. Carbon emissions and a loss of biodiversity are common side effects of traditional land management styles. Permaculture keyline design, on the other hand, is a land management practice that helps to combat these issues.
Keyline design is a land management practice that uses the natural ridges and contours of a property’s topography to slow, spread, and sink rainwater. Doing so allows rainfall to spread more evenly throughout the property, resulting in less runoff, more drought tolerance, and improved soil fertility.
In the rest of this article, we’ll discuss the history of keyline design, the key aspects of applying it to a piece of land, and the benefits it can offer.
The Origins of Keyline Design
The concept of keyline design was developed in the 1940s in New South Wales, Australia, by a man named P. A. Yeomans. In Australia, it’s difficult to retain water or improve the soil because of erratic weather patterns. Long droughts are followed by torrential rainfall, leading to massive runoff and soil erosion.
Yeomans, a geologist and an engineer, developed keyline design in an effort to utilize the land’s natural topography to circumvent these issues on his farms.
What Are The Steps of Creating A Keyline Design?
The first step in creating a keyline design is to understand the topography of the land and where water naturally collects. To do this, look at a topographical map of your property and take note of these characteristics:
Keypoints
A keypoint is the spot on a slope where the slope transitions from being convex to concave. In simple terms, this is where a hill begins to flatten out.
Keylines
To create keylines, a true contour (level) line is formed and marked going in both directions from the keypoint. Roads, treelines, or other landmarks are often placed along the keyline to permanently notate the location of the keyline.
Keyline Cultivation
After marking the keyline, plowing the land can begin. Each row is plowed parallel to the keyline, ignoring the normal contours of the land.
According to Yeomans in a 1955 video explaining keyline design, the first year of cultivation is called the “conversion year”. The ground is plowed several times during this year to help break up the heavily-compacted soil. In the following years, the ground is cultivated once per year.
What Does Keyline Cultivation Achieve?
Water naturally takes the shortest path to the bottom of a hill. This means that, in areas with steep hills and flat valleys, the water will travel down a single line on the hill and collect in the lowest part of the valley.
When this happens, little to no water is absorbed on the hill, while the valley below is flooded with water. This leads to soil erosion, a decrease in root depth, and a loss of nutrients in the soil.
Keyline cultivation helps to change the flow of water down steep hills. The trenches and ridges in the soil created by the plow give rainfall a slower route to take down the hillside. The water moves more slowly because it takes a less angled path down the hill.
Because the water is slowed down, it’s able to sink deeper into the soil. The altered water path also allows moisture to soak into ground that would otherwise remain barren and dry.
Do You Need A Special Plow For Keyline Cultivation?
While any plow can technically be used for keyline cultivation, P. A. Yeomans developed a specialized plow (aptly named the Yeomans plow) for this purpose.
The Yeomans plow works the ground without turning over the soil, meaning there are no clumps of dirt beside each of the keyline trenches. This is incredibly helpful because it causes less disturbance to the soil structure and prevents nutrients from being exposed to the elements.
According to Keyline Water Management, a field research company, this specialized plow also requires fewer horsepower to pull than other types of subsoilers. Because it can be pulled by a smaller tractor than other plows, the Yeomans plow is more accessible to small-scale landowners.
Irrigation Dams
Creating water storage areas is a crucial part of keyline design. This allows for water that overflows the keyline trenches to be captured and used during dry spells.
One of the easiest places to place a dam is at the keypoint of the valley. Because the keypoint is above the lowest part of the valley, water collected here can be transferred to lower elevations by gravity. Piping and valves are often used to easily move water from the dams to lower pastures.
Because there will be water runoff lower than the keypoint dam, another dam is often constructed near the lowest point in a valley. This will collect excess water between the keypoint dam and the bottom of the hill.
These ponds store water that can then be used to irrigate pastures or water livestock during a drought. In lands not managed by keyline design, this water is typically lost through runoff. Not only does this runoff reduce the amount of water available to the land, but it also carries away topsoil and nutrients.
What Are The Benefits of Keyline Design?
It’s clear that implementing keyline design on your property helps with water retention, but what are the long-lasting effects of this land management style?
Decreased soil erosion
As mentioned above, excessive water runoff facilitates soil erosion. This creates a negative feedback loop; when soil erodes, there is less to hold it in place, creating more erosion.
Because keyline design offers another route for water to take downhill, the overflow of water is greatly reduced. This results in less soil and water being carried down the hill.
The decrease in erosion also benefits nearby streams and bodies of water. Less erosion equals less sediment being deposited into waterways, helping to keep them clean and healthy.
Increased drought tolerance
The increased water retention, both beneath the surface of the soil and in irrigation dams, helps to make a property more drought tolerant. Water held in the soil lasts longer because it can sink deeper into the ground where it’s less likely to evaporate. When a dry season persists, pastures and livestock can be watered with the irrigation dams.
Increased carbon sequestration
The Yeomans plow plays a crucial role in the reduction of carbon in the atmosphere. When the plow works the ground, the soil is aerated.
This aeration gives plant matter (carbon) room to travel down deeper below the surface, where it decomposes. The buried carbon is then made available to growing plants, which helps create strong root systems and thriving plants.
Sinking carbon into the soil is a fantastic way to rapidly improve the fertility of the land while also lowering contributions to carbon in the atmosphere. This method of land management builds topsoil at much quicker rates than typical soil-building management practices.
Increased Yields
Because keyline design helps to create healthy, fertile soils, those who implement it on their properties experience higher yields. More abundant, dense crops equal a greater harvest and allow for a greater number of livestock per acre.
Increased independence
Keyline design is a sustainable way to become self-sufficient. The heightened water retention means less water is needed from outside sources, such as wells and municipal water systems.
Because the topography of the land is used to retain water and increase the nutrient levels in the soil, the land will largely care for itself. It requires less and less maintenance as time goes on.
The improved fertility of the soil also proves to be money-saving over the long run. Chemical pesticides and fertilizers can be very expensive. Thankfully, lands managed with keyline design principles rarely need to be treated.
Increased cooperation between farmers and environmentalists
Another important benefit of implementing keyline design is that it improves the relationship between farmers and environmentalists. Keyline design provides benefits for both farmers and environmentalists, creating a common ground for both parties.
Conclusion
P. A. Yeomans’ keyline design principles helped to show the world the benefits of sustainable agriculture. His understanding of geometry and geology allowed him to manage his land in a way that exponentially increased its fertility, yield, and water retention.
Though it was first implemented nearly 75 years ago, keyline design has skyrocketed in popularity in the past two decades. As farmers become more aware of unsustainable farming practices and seek to find a better way, they are increasingly moving towards this land management style.
Keyline design can be used on all properties, whether they are large-scale farming and ranching operations or small hobby farms. Even land without large ridges and valleys can benefit from keyline cultivation and planning.
Keyline design can seem complicated, but it’s actually quite simple to apply. It may take a few years to make noticeable improvements, but as time progresses, the benefits are unmistakable. The improvements to the land and environment pay for themselves rather quickly, making keyline design a choice even small landowners should consider.
