The plow

Introduction

Plowing has several beneficial effects. The major reason for plowing is to turn over the upper part of the soil. Plowing reduces the prevalence of weeds in the fields, and makes the soil more porous so that the seeding become easier and to get it easier for the utility plants to build up the root system. It brings more nutrient soil to the surface, among other things by raising the rain-percolated fertilizer and it deduces unwanted plants and disease bacteria.

History

The plow can be regarded as a development of the pick, or of the spade. The first plows, the scratch-plows, were probably taken in use as early as 8 thousand years ago in Mesopotamia. It consisted of a frame holding a vertical wooden stick that was dragged through the topsoil by humans or oxen. The first large improvement was to use metal to improve the edge so that it could cut better. The first commercially successful iron plow vas the Rotherham plough developed by Joseph Foljambe in Rotherham, England, in 1730. It was durable and light, and was engineered after the mathematical principles of James Small, who designed a moldboard that would cut, lift and turn over the strip of earth. However, all the major components of the Rotherham plough had been well known in China for millennia and diffusion of technology from China, probably by the Dutch, is highly likely. The plows today are in principle equal to the Rotherham plough.

A study of the today plowed field

If you wish to see if it is possible to improve a technology it is quite necessary to study the result you achieve with the today products. In this case the plow. I have here taken a picture (Picture 1.) of a plowed field that has been left unharrowed for a while to show how the weed survive in such a plowed field. Here you can really see how the today plows fails. This is because the plow furrow only turns over and lays itself on the edge of the previous furrow. Weeds, plant disease infection, vermin like mite and louse, get the possibility to spread up to the surface again and thus be able to live further. Therefore the plowing looses much of the effect it should have had. Normally you do not see this because it is hided by harrowing, but the problems are still there.
In addition the surface will be very large. The plow furrows get tops that easily are exposed to drought. Those together with the hollow spaces under the furrows that you can see very clearly in figure 1. increases the risk for lump building and early summer drought. This also contributes to one of the plowings worst problems; Soil erosion both from wind and water.

Picture 1. The picture is taken of a plowed field that has been left unharrowed to show the greatest weakness with today plows. Here you can see how effective the weed manage in a plowed field and how effective it continues up between the furrows and thus live on. Of course the same happens with plant diseases, mite, louse and other abomination.
Figure 1. This is how today plows places the furrows up on the edge of each other so that weed, louse, mite, plant diseases etc. can spread to the new surface and thus the plowing looses much of the effect it should have had. The surface become very uneven and the contact with the subsoil will be poor.

An analysis of what is so wrong with today plowed fields and plows.

The most important can be summed up in these points:

There are of course many other arguments against the old plow, but they here mentioned should be more than sufficient to go for a new generation plows.

Picture 2. Here you can see that it is totally free from weed on the up plowed side of the furrow. It will of course also pass for plant diseases and vermin if everything harmful from last season is properly packed down 8- 10 inches (20-25 cm) below the surface.

We leave out of account today plow solution and analyze independently what an ideal plowing result should look like. Then we can afterwards, with the present knowledge and technology find out how a machine should be designed to do exactly that in the simplest, most effective and energy economical way.

How shall a new plowed field look like in the future?

A new plow must turn the entire furrow 180 degrees upside down so that you bury the whole old growing surface with weeds, weed seed, disease infection, mites, louses etc. down at full plowing depth so that nothing of these can spread to the new surface and compete or damage the new utility plants. The field must get an even surface so that you get little dehydration of the surface. See figure 2. All the disadvantages that today plows have will disappear. Then you will get reduced costs in the form of investments, energy consumption etc. You will get higher crop and thus higher income.

Figure 2. Tthe plow furrows must be placed this way in the future. Quite upside down, tight against each other so that weeds, louse plant diseases etc. are quite buried on 6 to 10 inches (15-25 cm) soil depth without possibility to return to the surface.

How should then the future plow look like?

Well, here it is only to appeal to the imagination. We think we have the solution to how such a plow should be designed and I must admit that it was a great experience when we got the plow furrows to lay perfect 180 degrees, upside down already in the opening testing, but here remains some experimental running. When we anyhow shall design a quite new plow, we can just as well remove some of the other disadvantages as well, like large weight, costly design, demand for a large tractor etc. I am sure that you will be surprised by how much lighter, cheaper and more effective it can be made.

Reflections

"There is no one that plows anymore" someone will claim. Picture 3 shows the result. This should have been an oat field. Here grows nothing but weeds. The soil becomes so impenetrable for the utility plant roots that it hardly grows utility plants anymore. Here it will not be much crop. Measurements show moreover that for instance in Norway it is remnants of pesticides in more than halves of the farm water wells. Some poisonous substances are in the water wells in up to 20-30 years. It should not continue this way anymore and therefore it is time to look at solutions that can reduce the use of pesticides.

Picture 3. It is not always smart to drop the plowing. This should have been an oat field. Here grows nothing but weeds. More soil types become so hard, dead and impenetrable for the utility plant roots that they hardly survive and you can just forget to get crop.

But modern pesticides are not dangerous for people and they are quickly broken down in the nature we are told. That declared also the salesmen of the pesticide DDT in the 1960ies. Stories were told about salesmen that took a swallow of the pesticide to show how harmless it was, but we still haven’t complete survey over the damages DDT caused to the nature. New pesticids becomes launched with ostentatiously. One talks big of how effective and harmless they are for human beings. So, after some years the harmful effects appear like dandelion in lawn. The pesticide become forbidden, the chemical composition is a bit altered and the pesticide manufacturers appear with new and ”harmless” pesticides and the round dance continues. Therefore maybe it isn’t so stupid to plow after all.

© Tron-Halvard Fladby/ 22.9.2006