Soil Profiling

[Abby Brown] All right Theresa this looks like a fantastic little demonstration we have, what am I going to learn?

[Theresa Kruid] So we want to look at the particles and what makes up soil.

[Abby] Okay and we have two different types?

[Theresa] We have two different types, so think about what soil is made of. It's made of rocks and water, plant material, and air. Can you catch the air?

[Abby] No.

[Theresa] If we built all of that stuff together and then add lots and lots of time, like hundreds of years,

[Abby] Okay.

[Theresa] that's how our soil is made.

[Abby] Okay. Both kinds of soil are made that way?

[Theresa] Yes, it takes a lot of time.

[Abby] All right!

[Theresa] But there are different types of soil because they have three different particles. So this represents--we have three different sizes in here. The great big ones are the sand,

[Abby] Okay. Theresa, the little purple ones are the silt,

[Abby] Okay.

[Theresa] and those little tiny pieces are the clay.

[Abby] Okay, and those are the different types of particles in this type of soil?

[Theresa] In this type of soil, yes.

[Abby] Okay got it.

[Theresa] so have you ever done clay in art class?

[Abby] Oh yes.

[Theresa] It's really mushy and soft. Okay so that's gonna be slimy right.

[Abby] Okay and that's clay?

[Theresa] That would be the clay the little tiny pieces.

[Abby] Oh, the little tiny ones, ok.

[Theresa] Because those are going to really mush together. And then when we put all of this together those small pieces are going to fill in the big pieces and that makes up our soil. So that would be what we would might find in our forest soil.

[Abby] Oh! I see.

[Theresa] So if we look at this--

[Abby] And this is the soil that you've gotten...

[Theresa] Straight from the forest.

[Abby] Okay, great!

[Theresa] Right in the park. So we can see we have little bits of like roots, we have little seed pieces.

[Abby] Can I dump some out in my hand? Okay, oh yeah look at that nice and black. And some, like you said roots.

[Theresa] So all of that decaying material oh here's even a little piece of a leaf or a seed that's left over so eventually that will decompose,

[Abby] All right.

[Theresa] And of course our insects are going to help a lot with that.

[Abby] Oh, they eat them up.

[Theresa] They're going to eat it up,

[Abby] And then what happens?

[Theresa] And then they poop it out and that makes soil!

[Abby] Okay! And lots and lots of time?

[Theresa] Lots of time.

[Abby] Okay, so how long before this leaf becomes part of the soil?

[Theresa] Years; 50 to 100 years.

[Abby] Oh wow, that's incredible! Okay so this is soil from the forest...

[Theresa] Right, and then this jar is the forest soil also but we added some water. And you can see we have all of our smaller particles that sunk to the bottom; we can even see that water. And then the smaller humus layer all those little bits of leaves and stuff.

[Abby] So these at the top have not quite decomposed and they just float at the top?

[Theresa] Right.

[Abby] So after lots and lots of time, 50 to 100 years or more, what happens?

[Theresa] They would become like the particles down on the bottom.

[Abby] Okay! That's really cool! So that's forest soil. And I know this park has another type of very special soil...

[Theresa] Yes, the loess soil.

[Abby] Loess soil, okay.

[Theresa] So with our loess soil, instead of having three particles, it's going to have one; it is just going to have the silt.

[Abby] Silt, okay!

[Theresa] And they're kind of flat and stick together.

[Abby] Okay, so even these little sequins take on the shape of the particles and the loess soil?

[Theresa] Correct.

[Abby] Okay, should we take a look?

[Theresa] We sure can!

[Abby] Okay!

[Theresa] So let's dump some out and we have a little sample here, too, that we took right out of the ground. And then if you want to pour that.

[Abby] It's so soft; even these hard pieces break down into like powder almost.

[Theresa] So it almost feels like flour that you bake with. It's called sugar clay because when it gets wet it just kind of melts away down a hillside.

[Abby] Okay, I love that.

[Theresa] And then when we added water to the loess soil it didn't really separate, it just made kind of a mud pack.

[Abby] Well that makes sense to me because they're all the same size of particles so the water would get in there in even distribution throughout all of the evenly sized particles.

[Theresa] Correct. [Abby] Okay! That's a lot different.

[Theresa] What makes Stone State Park unique is the hills of this soil that we find here.

[Abby] The loess soil. And both of these types of soil, lots of types of soil, are found everywhere. What type of soil is in your neighborhood?

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