Soil, land and water conservation

MODERN SOIL CONSERVATION The 'dust Bowl' in the USA in the 1930's showed the american farmer that the soil is not infinite. Soil must be conserved and preserved for the benefit of this and future generations. Out of this nation toils came many far sighted and progressive farming developments, one of them was the Soil Conservation Service. This government service advises farmers on many modern soil and water conservation techniques, and acts as a clearing house for the new methods that are researched and developed by the USDA and other groups around the world.

Contour Plowing One of the first procedures that resulted from the dust bowl was the technique of contour plowing. With contour plowing the tractor operator will follow the contours of the hillside, in effect going around the sides of the hills following the contours of the hillsides. This technique is more troublesome and potentially dangerous than the old method of going straight up and down the hillsides that was commonly used before. The benefits of this technique are enormous however. The furrows thrown up by the plow will now act in effect as 'mini terraces' slowing or stopping the flow of rainwater and encouraging it to percolate into the soil. With plowing straight up and down the hillsides the furrows will act as ditches enabling the water to flow down them picking up speed and soil, increasing the size of the furrow, letting it become a ditch, then a canyon untill it reaches the harder subsoil with many tons of life sustaining topsoil carried away to the lakes or sea.

Strip Planting

In the dreams of the efficiency experts the ideal farm would be flat and contain fields with lengths of many miles. These large fields are indeed very efficient because they reduce the 'turn around' time of tractors at the end of each field. they also reduce the amount of non-planted space at the edges of fields that give the tractors the room they need to swing the long pieces of equipment around as a proportion of total field space. In this idealized version all fencerows between fields are taken out to reduce many small fields into one large field that is a model of efficiency.

The problems that result from this is that the wind can come along the field and roll for miles on that freshly plowed soil, the wind can roll along un-interupted picking up soil and not having to run into an obstruction that might reduce it's speed and cause it to slow down and drop it's load of soil.

With strip farming the farmer grows different crops each in it's own strip of one or two tractor widths. These strips ensure that there is allways a growing crop in the field, the wind may run along the freshly plowed portion for a while, but when it runs into the growing strip the wind will be reduced and will likely drop much of it's load of soil.

This method is more trouble than the 'mega-farm' method, but it holds the soil in place so the farm can be productive for a longer time. And in the end the higher costs should be seen to be worthwhile due to the soil being held in place.

Stubble Planting

This is a fairly new development that is well suited to many of the grain and cereal crops. In this method the old stubble of the years harvested crop is not plowed in as was the practice for centuries. Instead the inches high stubble is left in place, any fertilizers and new seed planted afterwards is inserted into the soil through small slits cut into the soil by a razor type device attatched to the tractor, in other words the soil is left virtually undisturbed. The stubble left on the soil will rot into the soil eventually helping the humis content as it would have when plowed in, but the stubble will reduce wind and water erosion while the new crop is growing. It also gives cover and habitat to small birds much more than would a totally plowed field.

cover crops

Cover crops are being used by many farmers here in California now, they were used for millenia in many parts of the world in the past, but the advent of the 'modern farm' reduced this idea to one of folly. The saying was 'cover crops are not a cash crop, why occupy the land with something you can't sell?' Nowadays however we realize the value of cover crops for their use in reduction of wind and water erosion, their ability to 'fix' nutrients from the soil for re-release for other plants. They add humis to the soil, reduce leaching of soil nutrients during high rainfall, and help hold the soil moisture to an extent depending on the growth stage, and soil and weather conditions. Cover crops, like many of the conservation methods used can increase costs due to seed costs, and extra tillage costs, yet it can have such high benefits that it seems to be a very efficient method to reduce costs overall when used between the main crops of a farm.

Cover crops will in some rare instances act as a 'nurse crop' planted along with a cash crop, the cover crop will generally germinate first, then it will shade the tender cash crop as it grows. This is a highly specialized operation, and much research needs to be done in this technique before it can be recommended for a particular crop.

Terraces Terraces have been used around the world for millenia, they are a highly effecient method of holding the soil in place on hillsides. They were not much used in modern times in the USA because of our large equipment and the fact that land was so cheap and easy to obtain if the old farm wore out. Old farms were often replaced by cities anyway as the bulk of the population moved west generation by generation.
Now however we are faced with the fact that there is no more free or cheap land, and we have to keep in good shape that which we have allready.
In the fifties the Soil and conservation Service started a massive campaign of terracing in the Midwest. Many farms were modified with massive terraces that hold down runoff, more percolation means bettter soil moisture and crop growth. The gentle hillsides terraced are now more productive, and have very little soil loss.

These are just some of the techniques many modern farmers are using to conserve the soil that all of us depend upon. Many of these methods were researched and developed by the USDA and the College Extension Service of the various states. These are some government programs that actually seem to do a bit of good, at least in this regard.

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