When it comes to equipment on the farm, there is an infinite number of options and combinations of those options.
Up until this year, we have mostly depended on a 3-bottom moldboard flip plow for our primary tillage. A plow is an efficient way to turn the soil and get the sod or green material to quickly begin breaking down in advance of preparing a seedbed. Plowing can be detrimental to soil structure, however, especially when done repeatedly. Plowing can also form what is known as a "hardpan" at the depth where the plow flips the soil, making it difficult for roots to penetrate (and thus have plants that thrive) and water to drain. After plowing, we have typically used a 12-foot offset disc for secondary tillage. Discing breaks up the clods and gets the soil closer to being ready to plant into. Sometimes we will disc two times. After discing, we use the rototiller to form a fine seedbed, and usually this is what we will either directly seed or transplant into. A rototiller does a great job of pulverizing the soil and making it nice and smooth for planting; however, that pulverizing action is not great for soil structure and all the organisms that live in it. Rototilling can also form a hardpan, like the moldboard plow.
A spader is one solution to all the problems the above implements create. Spaders literally have spades on them that rotate around an axle, copying the action of a garden spade by digging down, lifting and flipping the soil. Spaders can be used for primary tillage, but also to form a seedbed. Spading doesn't create a hardpan, and it is gentle on soil structure. In theory, a spader can eliminate the moldboard plow, disc and rototiller from an operation. The two biggest limiting factors of spaders are that they are very slow - less than 1/2 mile per hour, and they are pretty expensive, although these factors can be offset by the fact that you only have one piece of equipment to own, operate and maintain plus less diesel because of less passes with equipment.
We were lucky enough to receive a grant this year from the Human Links foundation to buy a spader. We are excited to put the theories of its use into practice and will keep you posted on how it goes!
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