Minnesota Farmer


Keeping our soil in place

I was recently asked about why we do not use old tractors and plows anymore.  In my last post I talked about some of the reasons we do not use that old small machinery anymore.  I would like to elaborate on one item here today.

When I was growing up we plowed every field, every year, with a mold board plow.  The purpose of a mold board plow is to turn the soil and plant materials that are on top so that it is completely buried.  This would take all of the last crops left overs and bury them, leaving the surface soil “black.”  It helped in weed control since many small seeded weeds could not germinate when buried so deep.  It was a matter of pride for farmers to plow so that the ground was completely “black” and smooth.  While this did help to make the ground ready for the next years planting, it also exposed the soil to the effects of wind and water.  Any ground with a slope would move down hill when water flowed over it.  Any high wind would blow the soil up into the air.  The last years plant material rotted quickly and became food for the next years crops, or all too often, ran off with the soil.

As time went on we learned that a smooth black surface between crop years was not in the best interest of the soil.  With the advent of new machines and new chemicals we learned to grow our crops with minimal disturbance of the soil.  Newer breeds of crops have been developed to grow better than the old ones in the presence of crop residue.  There are still times that a plow can work for the best interest of a soil, but many farmers are leaving their plow in favor of other methods of tillage that do not destroy so much of last years crop material.

I took the above photo to show the development of our soybeans last week.  If you look around the soybean pods you can see that the soil surface still has some of the previous years crop material on it even after months of weathering and machinery work.  The pieces of cornstalk and root can last for several years on the surface helping to protect the soil from the effects of wind and water.  The old machines of my youth cannot handle the crop residue left over on the surface.  New machines had to be developed to work in these conditions.  Some times we will even plant a crop right into the previous crops left overs without any tillage at all.  The old crop material can slow or even stop the emergence of a crop, but with the right machinery we can keep that effect to a minimum.

When I was younger, large wind or water events left their mark almost every year somewhere in our fields.  The lost yield and extra work this created was extra money we could not put in our pocket.  It could at times mean we could not pay our bills if the effects were bad enough.  I am proud to say that I have not had any noticeable erosion on the farms I work for many years now.  Places that would have gullies in them every year, now stay in place.  Erosion that would expose buried rocks, now leaves the rocks safely buried.  We manage our crop residue to help hold our soil in place.

The old days, and old ways are not always better.  In the case of farm machinery, I would not return to the old ways.  They were not healthy for the soil that I farm.  Today I know so much more about what it takes to keep my soil in place, and I make every effort to do just that.  I’ve learned to hold my ground in the face of wind and water erosion.

Michael