Fjordworks: Plowing the Market Garden
by Stephen Leslie with technical assistance provided by Kerry Gawalt, both of Cedar Mountain Farm at Cobb Hill co-housing in Hartland, VT.
Meditations on the Art and Science of the Moldboard Plow
PART TWO: Report from the Field
Just a generation ago the first step towards preparing a finished seed bed — commonly referred to as primary tillage — almost always began with the moldboard plow. These days both economic considerations and soil conservation concerns have steered many farmers in the direction of no-till, mulch-till, ridge-till, low-till, and strip-till practices that have largely negated the traditional role of the moldboard. However, for the horse-powered market gardener, typically managing a complex and varied rotation of cash crops and employing the extensive use of cover crops, the judicious use of the moldboard plow can still play a vital role in gaining successful harvests and achieving the aims of soil-conservation.
For most market gardeners the purpose of utilizing the moldboard is to renew a section of garden in order to seed it to a cash crop. When turned with the moldboard, carbonaceous cash crop residues or green manure cover crops are inverted, effectively wiping the slate clean for a new planting. Plowing soil that is of the proper moisture content can result in a pulverized and fine crumb-like consistency that will require little additional tillage before marking out rows for planting. However, beyond this basic function, plowing with a moldboard can have other beneficial effects. Plowing in the spring can open compacted soils and enable them to absorb more of the seasonal rainfall. Although it is true that deep plowing can bring weed seeds up to the surface, in the short term, a plowed field creates the opportunity to plant (or transplant) into a weed free zone. Spring plowing may also disrupt and kill injurious pests that have over-wintered in the soil or within crop residues.
These days most new horse-drawn plows are manufactured with Raydex-style shares. Essentially, what this means is that your new plow has a long-lasting chilled-steel share which can readily be replaced when it becomes too worn.
Depending on your soil type, other components of the plow bottom may also show wear with time and need replacement. The heel of the landside is another part that takes a lot of friction and usually has a replaceable plate on newer plows. By keeping a good point up front you can go a long way towards safeguarding the rest of the plow.
A general rule of thumb is that a plow bottom is designed to work at a depth which is approximately one-half of its width. So for example, the ideal plowing depth for a 12” plow is 6”. Horse-drawn plows are designed to work at a slow speed. The natural walking speed of a work horse is about 3 miles per hour. For the purposes of plowing we should try and hold them back to about 2 miles an hour. Experienced work horses that have learned to pace themselves will be happy to oblige as plowing definitely falls within the rubric of “heavy draft” on the scale of light to moderate to heavy.
Within the context of the market garden, the principal aim for utilizing the moldboard is to initiate the process of creating a friable zone for the root systems of direct-seeded or transplanted cash crops to establish themselves in, where they will have sufficient access to all the plant nutrients, air, and moisture they require to bear successful fruits. To this end, it is critical for good plant growth to render the soil into a fine-textured crumbly condition and to ensure there is no compaction within the root zone.
The cheapest and best way to feed the cash crops in the market garden is to rely on homegrown inputs. The two most obvious ways of doing this are: 1) To maintain livestock and make compost by mixing carbonaceous plant matter with their stable manure, and 2) Utilizing cover crops (including legumes) within a regular garden rotation.
Nutrient amendments added to the soil need to be thoroughly mixed into the top five inches of soil because this is typically the zone in which the majority of vegetable cash crops will set their roots. One effective means of delivering finished compost to this root zone is to spread the compost over a cover crop immediately before plowing and then set the plow to a shallow tillage depth which we refer to as “skim plowing” in order to thoroughly mix both the nutrients in the compost and the nutrients tied-up in the cover crop (roots and vegetative top-growth) within this zone of the top five inches of soil. To skim plow we need to set the share to cut a wide furrow at a shallow depth, so that we are turning the soil at a depth of between 2”-4”.
In the following section, Ken Laing, who along with his wife Martha, owns and operates Orchard Hill Farm, gives us an in-depth description of the why and how of using the moldboard at their diversified farm. Orchard Hill Farm was established by the Laings in 1979 on land that had already been in Martha’s family for six generations. The farm consists of 80 acres and includes a 185 member CSA, field crops, including: oats, rye, hard winter wheat, hay and pasture, composting hogs, and seven Suffolk Punch draft horses.
Report from the Field:
The Use of the Moldboard Plow at Orchard Hill Farm
by Ken Laing of Orchard Hill Farm, St. Thomas, ON
The moldboard plow plays a very important role on our farm both in our CSA garden (7ac in production each year), in cover crop management and in the production of feed crops for our horses and other livestock (63ac).
A lot of tillage implements depend on the weight of the implement to give it penetration. This results in very heavy implements for dry, hard soils and very heavy draft. The moldboard plow is a very clever invention because it uses the weight of the furrow slice on the share and front of the plow to keep it in the ground even when the soil is quite dry and hard. The twist in the moldboard results in the inversion of the furrow slice and thus the crop, cover crop and/or weeds growing on the surface are buried and killed setting the stage for a clean start for the next crop. Any other implement would require multiple passes and the passage of considerable time to create such a good seedbed.
Yes the plow can be overused and often has been in cash crop operations where fields are plowed every fall and left bare over winter except for snow cover until spring. Although we use a plow at strategic points in our rotations we have a goal to leave no field bare for very long and particularly over winter.
In our CSA rotation for the bulk of our vegetables it is a 2 year rotation with one year of cover crops and one year of vegetables. As the vegetables are harvested either the whole section is worked and planted to a cover crop or the cover crop
is planted between the rows and left over the winter. In the spring the whole area is plowed and planted to white mustard, a weed controlling and biofumigant [nematodes and perhaps wireworms] cover crop. For good biofumigant action the green mustard must be plowed under at flowering but before seed set. A second cover crop of oats/peas is planted for fall/winter cover. Depending on the amount of biomass it may be just disked in but if too heavy may require plowing especially for early crops (last week of March or 1st week of April here in southern Ontario).
When the ground is mellow we can plow with 2 horses on a Pioneer sulky plow with a 12” bottom. When the ground is dry and/or it is hot we switch to using 3 horses. Plowing requires a lot of driving skills to keep the horses in their proper positions to maintain a uniform width and depth and keep the plowing straight. Because we are always training 3 or 4 apprentices, I prefer to use 2 smaller hitches of 2 or 3 horses, that way I can be in the field to assist the apprentice teamster and to keep things reasonably straight so finishes are easier. Three horse hitches are trickier to drive because there is yet another horse to keep track of and since we use team lines with 2 jockey straps the teamster has a direct connection to only 1 side of the 2 outside horse’s bits.
You want your team to walk out with their heads as straight as possible for your horses comfort. For a 2 horse team your double tree wants to be 32-34” long from single tree clevis to single tree clevis for a 12” bottom. Your neck yoke should be close to this length as well. If you have a wanderer or one horse that is a little faster put that horse in the furrow. It will give the wanderer something to follow and the fast horse will have to concentrate on staying in the furrow and that will slow him down a little. I am not against putting a knot in a line as a quick fix to shorten a line. Just keep it close to the bit so that it does not get hung up in the hame ring. This will help to slow a horse by bringing its head in toward the other horse or help to keep his head straight. It is important for the land horse to walk just the right distance from its teammate in the furrow. Usually if there is 6-8” between their bellies that is about right. You do not want them bumping into each other as it will knock the furrow horse off balance and make it hard to stay in the furrow. If your land horse is sloppy [or you are a sloppy driver] and gets too far to the left your plow will likely jump up out of the furrow. Because of the cross-over in the lines driving with a lot of tension tends to bring your team together, less tension will let them walk further apart. It is very important when plowing that your horses pull together evenly. Sometimes I will put a knot in both lines to a particular horse if they are too fast or more ambitious. Some horses like more tension because it gives them more direction. Other horses resent the tension and drive better if left with almost no tension.
We have 2 Pioneer sulky plows. These plows have plenty of clearance and a big rolling coulter which helps them deal with a lot of trash. I prefer them over the foot lift model because they are lighter in weight. The first Pioneer I purchased had a Raydex [Oliver] bottom which made a mess in sod and clay soils. It is not just the Raydex share that I find unsuitable for sod or clay soils but the shape of the whole bottom. In sod or clay the furrows tend to be thrown over in a very irregular fashion creating a very rough job that is then very punishing for teamster and team to pass over the next time.
This plow was converted to an International Ace 12” bottom. This bottom was very common 50 years ago in Ontario on tractor trail plows. It has a relatively narrow point and longer twisted moldboard. For the conversion I had to drill 2 new holes in the International frog and weld an extension to the coulter to move it ahead 6”.
My second Pioneer has a Kvernland 12” bottom but it is a lighter, older bottom than Pioneer now sells. It will plow a very similar furrow to the Ace. I had to extend the coulter forward for this bottom as well. This bottom has Kvernland’s reversible point which is inexpensive and easy to reverse. This bottom has Pioneer’s rolling landside wheel which eliminates replacing or building up worn heels on the landside and also allows you to back the plow up in some situations.
Both Pioneer plows have been further modified by turning the furrow wheel inside out to narrow the furrow, by placing a helper spring on the land wheel lever and installing a tongue which only pivots up and down. Laterally the tongue is rigid which helps keep the plow straight while finishing. For extreme summer plowing when the land is dry and hard having a properly shaped and sharp share makes a huge difference in keeping the plow in the ground and maintaining the correct width of furrow. As the plow encounters a lot of resistance to moving through the soil and because the horses are hitched to the bridle of the plow (the “bridle” of a plow is the horizontal plate with adjustment holes that the evener attaches to via a clevis) and not directly to the point of the share there is a levering effect which will cause the plow to rotate forward, lifting the rear of the plow slightly or a lot, negatively affecting the formation of a nice furrow. Welding a bracket onto the plow allows the addition of up to 3 concrete blocks to counter this lifting action.Some years we have plowed up to 25 acres although it was spread over the season, some in the spring, some in summer and some in the fall. Plowing is excellent work for horses because it is repetitive and serious work. It makes good well broke horses.
In this article we have focused on the use of the moldboard plow. As we have seen, this tool that once so revolutionized agriculture in the Western world, still has great value to the small horse-powered farmer of today. The plow can be understood in a symbolic sense as well. It mines into the depths of soil to reveal hidden treasures of nutrient and creates tilth for roots to thrive in. The plow share represents both change and renewal. What was — must be turned over — to make room for that which is to come. The world we have known is vanishing. A new world is hurtling toward us. The consumer culture, with all its fake promises of unending technological fixes to every human problem and need, is crumbling before our eyes. More and more we are asked to face the reality that the bio-sphere is a closed-loop system that requires us to wean ourselves away from energy and power sources that are non-regenerative. Meanwhile, the powers-that-be continue to wage a campaign, plying us with electronic gadgets and pharmaceuticals in an attempt to keep us mesmerized as the multi-national corporations fill their coffers extracting every last drop of fossil fuel from the earth’s most fragile and endangered ecosystems.
Memory and instinct are becoming important to us once again. We hunger to restore diversity to our personal worlds and we want more direct contact with our immediate environment. To do this we need to regain the intelligence required to build a human culture that recognizes the sacredness of all life — that experiences the Universe itself as a Living Being (what the Ancient Hebrews once referred to as a “Living God”). To do this we need to regain the humility and compassion of a people who know their place within a given landscape. We need to build a society whose foundation stone in every quarter is nothing more nor less than the living soil.
In all the major spiritual traditions of our world, discernment has always been recognized as a crucial quality for the seeker of truth. On an elemental level discernment is what we use to tell the true from the false. Through the practice of discernment wisdom grows. The farmer too must practice discernment on a daily basis; he or she must decide when to sow and when to reap, which one to breed and which to cull. The farmer also faces such choices as: Which tools to employ? On what scale to farm? Just because farming can be done with genetically modified organisms, satellites, robots, and harvesting machines that cost one million dollars, doesn’t mean it should be done that way.
Today there are many young people in our society who are heeding the call to make their living from the land. Increasing numbers of them are also growing intrigued by the concept that many, if not all, tasks requiring traction on the farm can be economically and efficiently accomplished with live animal power. The work horse is being recognized as an ally that can help us find our way back to a path that leads to life.
When we put our hands to the handles of a plow we are engaging in a task and following a path that many ancestors have trod before us. With a good team of horses, mules, or oxen out in front of us and the soil in fine tilth turning over in neat furrows behind us, we find ourselves at the nexus of a new agricultural revolution. To get to this point, we have taken a step back from the point of view that would have us believe that every new technology represents progress over what has come before. Instead, we have used our own discernment to discover the tools and power source that feeds us body and soul.