Key Line Design – Reshaping Future Farmland

May 20, 2021

At the Bailey and Sarah Williamson Farm & Nature Preserve in the Walnut Hill Historic District of eastern Wake County, you can lose yourself in the tranquil scenery, totally forgetting the state’s capital lies just 20 minutes west. This special place is more than a nature preserve and farm, though, it’s an integral piece in protecting the history of the region and connecting the community with nature for generations to come.

In 2018, TLC partnered with the Regenerative Design Group to create a comprehensive Agricultural Concept Plan for Williamson Preserve to guide staff-led stewardship and restoration work at the property. One such project is an innovative regenerative agricultural water management practice, known as Keyline design.

This practice helps conserve water, reduce erosion and nutrient runoff, and increase carbon sequestration in soils. By demonstrating the use of keyline design, TLC’s strives to spur wider adoption of regenerative practices throughout the region, provide public education, and serve as a model of how farmers and other land stewardship organizations can conserve their water and soil resources on working lands.

Regenerative Agriculture is not a new practice— it has been in use on farms around the world for hundreds and thousands of years. Many of these practices have been lost in recent years, but TLC is part of a growing movement to learn from others about the current and historical agricultural systems and practices that replenish the soil, create healthier air, support cleaner water supplies, and lead to flourishing ecosystems.

Long before the arrival of Europeans, Indigenous populations of the Americas protected local ecosystems and preserved biodiversity through land management and farming practices. For example, Indigenous Americans planted more than one crop together, in a practice known as intercropping, for hundreds of years. These methods directly echo the “polycultures” of today’s sustainable farms.

Around the turn of the 20th century, the work of Dr. George Washington Carver would revolutionize the field of agriculture. Carver, an agricultural scientist, inventor, and educator at Tuskegee University, focused on revitalizing and building soil health. Not only was he famously responsible for our beloved peanut butter, but he also helped lay the foundation for soil health and conservation, especially on small southern farms. Many practices such as crop rotation, erosion control, and composting have their roots in his work. Many of these practices highlight the need to not just focus on soil resources, but also water resources for agricultural production.

In the 1950s, another innovator in regenerative agriculture, P.A. Yeomans, introduced a system of land management known as the Keyline system, which many consider to be well ahead of its time. During this time, most believed that soil was a finite resource that must be conserved, similarly to rare metals. Yeomans understood that carbon cycles create soil, but also that this process spans centuries.

By adjusting the conditions in the soil with his plowing and management techniques, P.A. was able to speed up this process and create dozens of millimeters of fertile topsoil in just one year. Besides this contribution, Yeomans also made advances in the understanding of landscape geometry— by synchronizing with the natural geometry of the land, a farmer can drastically alter the way water interacts with it.

As Yeomans himself wrote, “The objective of the pattern in Keyline pattern cultivation is to direct the shallow overland flow, which results from rainfall runoff, to remain evenly spread and not follow its natural flow path to concentrate in the valley shapes. The same technique also provides the means for evenly spreading the water in the system of “hillside” irrigation named “Keyline Pattern irrigation.” It is the Keyline pattern cultivation that can convert what is commonly called “wild flooding” into fully controlled irrigation.” Consequently a well-planned drainage system can provide two key benefits, storing water for uptake by trees and reducing storm water runoff and protecting our downstream waterways.

By transitioning from a system of soil “conservation” and depletion to one which builds soil health, the land becomes more fertile over time, rather than less. For this reason, P.A. Yeoman argued that soil creation and the Keyline system would lower the costs of the farm while producing higher yielding harvests— which means more profits for farmers along with improved health of the land they farm.

It is in the same spirit as P.A. Yeoman, and the many stewards of the land that preceded him, that Triangle Land Conservancy is implementing Keyline design at Williamson Preserve. To work in concert with the land, rather than to attempt mastery over it. To draw upon the wisdom both of those who came before us and of nature itself. To manage farmland in a way that is the least intrusive and most sustainable.

This spring, through generous funding from Triangle Community Foundation, TLC staff worked closely with nationally recognized agroforestry consultant, Mark Shepard and his team from Restoration Agriculture Development (RAD) to design and install a 16-acre sustainable water management system incorporating Keyline design in the Chickasaw Plum field at the Williamson Preserve. Six thousand linear feet of bioswales now crisscross a farm field that was in need of habitat restoration, storm water mitigation, invasive species removal, and soil health improvements. The field leads directly to a stream that runs south across the preserve to the Neuse River.

This field is the home base for local tree company Leaf & Limb on their new “Project Pando” initiative (read more at Project Pando, which has a long-term agreement with TLC at Williamson Preserve, is a volunteer-driven operation that is sustainably growing native trees to give to the public for free. Project Pando staff and volunteers will be the site stewards of the Keyline design system, along with TLC staff, as they continue to plant native trees, shrubs, and grasses over the next ten years.

Implementing Keyline at Williamson Preserve will conserve water, reduce erosion and nutrient runoff, and increase carbon sequestration. By demonstrating the use of keyline design, we also hope to spur wider adoption of regenerative practices throughout the region, provide public education, and serve as a model of how other land trusts can utilize protected farmland in the fight against climate change. Keyline design and practices like it have a long history of benefiting the land and farmers of the past. At TLC, we hope to use these tools to ensure the thriving of the land and farmers of the future.

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