When Dan and I first read Sepp Holzer's Permaculture, we were quite surprised at the heavy equipment Sepp used when he was setting up his farm. He totally rearranged the side of a mountain with a variety of earth moving equipment. At that time, we were meandering down the path of more natural farming and gardening and had come to see massive plowing and tilling as destructive. Because of that, his massive earthworks were shocking.
Thanks to my online permaculture design course, I'm learning that earthworks are the foundation of permaculture design. I'm starting to understand the when and why of earthworks, and how it differs from traditional uses of equipment and machinery. Plowing and tilling are seasonally repeated actions that destroy the soil ecosystem. Permaculture earthworks are carefully planned one-time projects with a specific purpose in mind. That purpose usually revolves around capturing and keeping as much water on the land as possible. Two common examples are ponds and swales. A less common one is ripping the soil.
Ripping is a soil conditioning technique. Have you ever dug a hole in the ground after a heavy rain? I have, and have been shocked to discover that after a good, long, soaking rain, the soil is only moist in the top few inches. The soil under that can be bone dry. This is common anywhere plant growth has been kept short, and/or the area sees a lot of traffic from either herds of animals or heavy equipment. Plants compensate for being mown or eaten by pruning their roots to match the top-growth. If that top-growth stays short, the roots stay shallow, so nothing penetrates the soil including water and oxygen.
In a natural system, deep-rooted trees and plants keep the subsoil from becoming compacted. They also pull up minerals from deep within the soil, for the benefit of the plants and everything that eats them.
In Australia, a Wallace plow is used to recondition compacted soil. It is designed to specifically open a line in the soil at whatever depth it's set to. It doesn't necessarily tear up and turn the soil, but slices the soil to allow plant roots, air, and rain to penetrate. The soil ecosystem is preserved. The following are from an illustration in Bill Mollison's Permaculture: A Designer's Manual (PDM), page 218, figure 8.11.
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Short grasses (from mowing, grazing, or heavy traffic) cause short
roots. The soil is dense and without the structure needed to hold water and air. |
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Forage growth from 3 rips with the Wallace plow at various depths: 2-4 in (5-10 cm), 5-8 in (12-20 cm), 9-12 in (23-30 cm). |
I've dug into our soil in numerous places and know how dense and dry the soil is, even one shovel-depth deep. So, I tried to research Wallace plows in the US but came up with nothing. What we did find, was a subsoiler. It's only single shanked, but Dan says the depth can be adjusted somewhat, although not as much as the Wallace plow. Still, something is better than nothing.
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| Soil ripper aka subsoiler. |
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| Action shot. |
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| Parallel rows in the pasture, made on contour. |
