Organic Soils vs. Conventional Soils


>>Hi. My name is Val and I am a science gal.
Today we’re going to be talking about soil – especially the difference between organic,
and by that I mean organically managed soil and conventionally managed soil. So today
we’re going to be looking at two samples. These are actually from the same soil type.
They were taking fifty feet apart. This soil has been managed continuous with corn and
soybeans for the last ten years. Corn and soybeans are annual crops that are taken off
at the end of each year. This soil was corned two years ago and then it was planted down
into a pasturement. And it was used for hay and this year it will be pastured. To understand
main differences in how farm management determines soil health, we need to look at something
called soil structure. In another video clip we talked about soil texture. Soil structure
is actually the way soils are arranged the particles and how they cling or aggregate
to each. It’s considerate the teamwork aspect of soils. Soil structure can be altered; this
is different from soil texture which is just a natural state of soil in an area. Texture’s
a given just like the genetic DNA you were born with. Soil structure, however, can be
altered by different farm management systems especially organic in perennial cropping.
I’m going to illustrate what happens with these two different soils – actually, again
the same soil under different management – when it rains. Here, the soil does not stays together.
It basically dissolves under rain. This soil, however, when it’s rained on especially when
it the rain hits the upper canopy, does not dissolve as rattling. It stays clump together.
You can see the difference already and how much soil is washed out of the system depending
on the sun management. Here I’ve given the soils the chance to settle out and you can
again tell the organically managed soil from the other soil where the particles, the finest
particles, still have not settled out of the rainwater. This is what causes pollution,
run-off pollution, from farm fields. If you have a well-managed organic soil, you don’t
get nearly as much run-off pollution because the soil particles cling together. I’m going
to do another demonstration. Here again is a bucket of soil that’s being managed currently
as corn and soybeans. These, by the way, are small soybeans growing in the field. Here’s
the soil that’s being managed as a perennial crop. You can see the root structure and how
that alone would be holding the soil together. I can pick up this entire clad of soil that’s
hanging together rather nicely. And, again, if we pour our rainwater over this, you can
see what’s coming off is clean; virtually nothing coming off. Here I can’t really demonstrate
the concept because i can’t really pick up the soil in keep it intact – it falls apart.
But once again if I rain-watered it, it basically dissolves in my hand and it’s running brown.
Here, that plan is going to have its nutrient put right next to the root because the soil
itself doesn’t move the nutrient around enough for the plan to take advantage of it. The
same will happen when there’s a rain storm event the soil will be hard and rainfall will
not be able to go into the soil. It’ll just run right off. In fact, after the rain event,
here is what you would see the difference of the two soils once again – the hard-baked
clay or the organic soil. So for people who say there aren’t really any differences between
organic and conventional farming, I say organic soil is the foundation of organic farming.
And we are ruining our soil structure and our soil. We can’t win our soil texture but
we can ruin it, ruin its structure by continuous role cropping year after year. On the other
hand, we can actually improve organic matter and till in this type of soil we can improve
the life, the macrobiotic life, in the soil even the microscopic life so that it starts
cycling nutrients and allowing plant growth without being dependent on inputs that have
to be adjusted narrowly to fit the plant. We also don’t know have as many weeds in the
system because the plant grows very nicely and covers the whole system versus this where
weeds will spring up in between the plants, isolated plants, unless used an herbicide.
And the herbicide in term kills the soil life and it’s a never-ending battle with nature
to get just this plant enough to rest. One other thing to note is look at the corn stock
residue from this sample that had not broken down since last year and in an organic system,
you won’t see the residue from the previous year’s crop because the earthworms, dung beetles
and other macro invertebrates will come up taken at all down and recycle that material
and turned it into nutrients available for the plan. Here, again, I’m going to show the
difference between a soil that has a perennial crop with the fibrous root system throughout
that hangs together pretty well verses this soil where there’s really only one life root
and that’s the root that the farmer planted for the soybean. That’s actually not too bad
but that’s all the organic matter that’s going into the soil verses this. So when you think
about carbon syncs and carbon sequestration this again is why grasslands will sequester
a lot more carbon and annual crops. Look at the massive fibrous root hairs and carbon
in here verses what we have here.

1 thought on “Organic Soils vs. Conventional Soils

  1. What is you were growing soy beans organically? Would it have a more dissolving soil structure or would it still be clumped limiting run off? Conversely, what is you were growing pasture crops conventionally with chemicals?

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