No Till: Some reasons not to plow pt. 2, Sand, Silt and Clay

Last post, I explained that I can’t afford to till the land and expect a profit.  I also think that any method other than a no till method will impoverish the soil.

I need to give more background to explain why tilling can kill the processes that build up soil.  This may take a bit, but I hope you stay with me.

Let’s talk about the inorganic part of your soil.  There are three ingredients (not including big rocks):  sand, silt and clay.

Sand is just ground up rock.  Water percolates through it very quickly.  Sand can have sharp edges or be rounded.

Silt is ground up rock as well, but much smaller than sand.  Water will stay in it longer than sand, but that’s not saying much.  Silt usually feels softer than sand, because it is made of smaller pieces.

Clay is inorganic as well, and made of teeny tiny bits.  But something else has happened to it.  Usually, water and/or heat have changed whatever it used to be into tiny crystal structures.

Imagine a volcano throwing lots of ash into the air.  The ash lands on the ground forming an inches thick layer.  It may turn into one type of clay.  The same ash may fall into a lake.  The hot ash and the water may cause a different kind of clay to be formed.

Clay holds water very well.  In fact, clay can keep water from soaking into your soil if there’s a lot of it.

Clay does one other thing that I think is pretty neat.  It can hold an electrical charge.  This is important because a lot of nutrients have a positive or negative charge.

Your soil has at least one of the above in it and most likely two or all.  Let’s put all of this together.

Positively and negatively charged nutrients are at the very top of the soil.  This is where plants break down, animals do their thing, etc.  Then, the rain comes.  The nutrients are in the rain water and begin to soak through the soil.  They pass the sand and the silt.  Some nutrients are caught by the clay.  If there’s enough rain, most of the nutrients will wash into the water table.  Your plants won’t see them.

You may have enough clay to keep the nutrients up at the top.  In this case, you probably don’t have enough sand or silt to to let the water into the ground to any depth.  In this case, the water doesn’t soak in and gets baked out of the soil by the sun.  There’s no water storage.

So how do you keep nutrients if you don’t have clay?  If you have clay, how do you get get the water to permeate your soil?

I’ll post about the fix in part 3.


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