Here’s an update about the keyline cultivation system that I covered in a previous blog post titled Restoring Degraded Land. Building soil on degraded land is one of my biggest passions lately, because this is what the world needs now. Scientists say it takes nature between 100 to 1,000 years to form an inch of topsoil, depending on local conditions. The keyline system can form 4″ of good topsoil in 3 years by chiseling grooves in the ground with a simple farm implement.
From Managing Wholes.com: “The late P.A. Yeomans, developer of the Keyline system of land management, recognised that the sustainability of the whole farm was dependent on living, vibrant topsoil. The formation of new topsoil using Keyline principles, at rates not previously considered possible, was due to the use of a tillage implement designed to increase soil oxygen and moisture levels, combined with a rest/recovery form of grazing and pasture slashing, to prune grass roots and feed soil biota. Yeomans was able to produce 10 cm (4”) of friable black soil within three years, on what was previously bare weathered red shale on his North Richmond farm.”
Compare this to Biointensive gardening that claims a rate of soil building of 6” inch of topsoil in 50 years, which is 60x faster than nature. This is pretty impressive, but not nearly as fast as the keyline system. Keyline can build 66” inches of topsoil in the same time period. That’s 11 times faster than Biointensive gardening. Plus, keyline is way less labor intensive. Biointensive is based on double digging raised beds and making ex-situ compost, which are very labor intensive.
So, chiseling grooves on contour can build up 4″ of black topsoil in 3 years with keyline plowing! This is very encouraging given the sad state of the environment these days. Keyline cultivation is suitable for small plots and commercial scale farming. Note how keyline plowing is far simpler than making large swales on contour — what many permaculturists do — and that can be a costly earthworks project. Also note how he did not bring in truckloads of manure, leaves, compost, etc. The grooves on contour triggered the soil building process naturally.
You don’t need a large tractor to do this. You could use a miniature tractor like farmers use in many developing countries. This means most anyone in the developing world can do this, even in countries where the soil has been badly degraded. In summary, keyline cultivation is a fast, easy, simple way to build lots of topsoil.