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ASHLEE DERE: OK. Now that we've got our subsample that we've pulled from each horizon, we can go ahead and do the color and then textures. So we'll start with our Munsell color books. These are full of little chips that have different colors on them that represent what kind of colors you would see in soil-- so anything from red to yellow to brown. I even have some dark colors for soils that are saturated with water.
So we'll take a little ped of soil, get it moist like we did in the beginning when we are wetting the soil profile to better see what colors we had, and then try and match it with one of these little color chips in here. And each page is a difference hue, which is saying whether it's yellow, brown, or red. And then there's a value and a chroma. And the value is how light or dark that color is. And the chroma is how bright that color is.
The 10YR is kind of your classic yellow-brown soil color. You usually start there and then you can determine whether it's yellower or redder and move to different page. You just take a little piece and put it behind the chip.
TIM WHITE: Well, Ashlee, I get a 10YR34.
ASHLEE DERE: That's an excellent call. So we have a brown surface horizon that's not really dark. But it's somewhat dark.
TIM WHITE: What next?
ASHLEE DERE: Now we have texture. So we get to get dirty. This is the fun part. So we're going to basically feel how much, first of all, clay is there. That's the easiest thing to feel in a soil.
And then secondly is sand and silt. You can feel it, but it's hard to quantify silt alone. So since they all add up to 100%, the sand, silt, and clay fractions, we deduce silt most the time.
So there's several different methods to figuring this out in the field. And the first is the ribbon method where you squeeze the soil sample between your thumb and forefinger and see how long of a ribbon breaks off. I'm not as familiar with that method.
I prefer the wire method, which is what you're doing now, rolling the soil between your palms to make a wire little worm. And you can pick it up off center and see how it behaves. I'm getting that it breaks off a little bit.
For this to work well, it has to be pretty much the right moisture, which is hard to get. It just requires working and rolling it out between your hands. You want something about the size of a pencil.
Yeah. That looks pretty good. And then picking it up off center and shaking it a little bit gets it to fall apart for me. So we have different breaks.
TIM WHITE: So wouldn't you get breaks once you've--
ASHLEE DERE: Breaks when shaken so we know that we have between 18% and 26% clay in this sample. So we're estimating about 22% clay. So now that we figured out of percent clay that we, we can determine how much sand we have.
One way to do this is to listen to the soil. So you can hear sand. It's a very gritty sound. So you can hold up to your ear and squeeze it together and listen for kind of a snap, crackle, pop kind of sound. And that's the sand grains rubbing against each other.
So we definitely have sand in here. And another way is to do what you're doing of getting it really wet and essentially filtering out anything that's not sand. So you get a piece of soil really wet and kind of drain off all that silt and clay. And what you're left with is the sand grains that are visible.
So we definitely have sand in here. You can feel the grittiness when you push down on your skin. So now we need to estimate percentage. So either we're on the sandy side or the silty side. But we feel quite a bit of grittiness. So we've got a considerable amount of sand.
So basically we're choosing between a sandy clay loam soil texture and a loam. Pretty equal on the percentage of sand, silt, and clay that we have. So we're going to call it a loam.
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And the last part we have to do before we can go back and synthesize everything we've seen is look at the moist consistency of the soil. And that's basically how easy or difficult it is to crush a soil ped in your fingers. And this just gives some indication of how hard the soil is.
You just take a little piece of the soil and get it wet and try and moisten it. And then try and crush it. If it crushes really easily under your [INAUDIBLE].
Ideally, you have a moist soil profile just after a rain. So it would be moistened throughout but it wouldn't be overly wet. And the problem with doing it ourselves is that we have a tendency to get it too wet or not thoroughly get the soil wet enough.
TIM WHITE: Firm or very firm, even.
ASHLEE DERE: I'd say firm. So now we've finished describing everything that we need to do for each and every horizon, we can go back in and look at the bigger picture again and essentially name each horizon, describe the main properties there and wrap up the whole thing.
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