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We're going to spend a few moments talking about the textural triangle.
Texture is one of those components, the physical properties of soil,
that's very important.
So, the first thing that we like to do at the textural
triangle is divide it up into three components.
We have what are called the loams, which go from zero up to about 26% clay.
Loamy sand, sandy loam, loam, silt loam, those are considered loams.
>From 26 to 40% clay, those are considered the clay loams,
sandy clay loam, clay loam, and silty clay loam.
Anything above 40% clay, those are considered clays,
so sandy clay and silty clay.
One thing you wanna know about the textural triangle, and
I usually tell my students in the introductory soils class, is that rarely,
if ever, you're gonna have pure silt, or pure sand, or pure clay.
So, actually,
now you only have really nine textures that you really need to deal with.
Those soils, which are on the right side of the textural triangle,
those are usually soft and very smooth.
They feel like talcum powder, actually.
Those are the silts, silt loam, silty clay loam, or silty clay.
Those soils on the left side of the textural triangle
are very gritty in texture.
They're sandy clays, sandy clay loams, sandy loam, and loamy sand.
Now, if you're texturing a soil and you can't quite figure out exactly,
it doesn't feel smooth and it doesn't feel real gritty.
Well, that means you're right smack in the middle of the textural triangle.
Those are gonna be the loams and the clay loams.
So let's go ahead and texture a couple of samples.
And I'll show you how to go about actually doing a soil texture.
The first key thing about texturing a soil
is to make sure you've got enough material in your hand, enough soil.
I would say have about a golf ball-size clump of soil in your hand.
And once you have that, what you're going to do is
move it around in your hand and try to get an idea about, how does it feel?
Does it feel really smooth, or does it feel gritty?
In this particular case, this sample feels really smooth.
And then once you have an idea of the coarseness or the smoothness
of the sample, what you wanna do is press it up between your thumb and forefinger.
And if the sample doesn't form a very long ribbon,
that's gonna tell you it doesn't have a lot of clay in it.
So chances are the texture of this particular sample,
which is really smooth, not a lot of clay, is going to be a silt loam.
Now over here, we can contrast that with another sample,
and this sample feels smooth.
And I'm pressing it out in the palm of my hand, and
now I'm getting ready to press it out between my thumb and forefinger.
And what you notice about this sample is look at that ribbon.
And that ribbon tells you that there's a lot of clay in that sample.
In fact, it's a smooth sample, all right?
It has a fair amount of clay in it.
Chances are it's either a silty clay loam or a silt loam.
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