Solved Lab 7 Name: THE SOIL TEXTURE TRIANGLE, Different | Chegg.com - Free Printable

Let's solve this step by step using the Soil Texture Triangle and the given data.

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🔍 Understanding the Soil Texture Triangle

The soil texture triangle is a graphical tool used to classify soil based on the percentages of sand, silt, and clay. The three sides represent:

- Bottom: Percent Sand
- Right side: Percent Silt
- Left side: Percent Clay

Each point inside the triangle corresponds to a specific soil type, based on the relative proportions of these three components.

> Remember:
> Sand + Silt + Clay = 100%

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We are given several soil samples with their percentages. We need to:

1. Fill in missing values (if any) so that the total adds up to 100%.
2. Use the triangle to determine the texture name for each sample.

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✔ Let's go through each part:

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#### a)
- % Clay = 30
- % Sand = 10
- % Silt = 60
- Total = 30 + 10 + 60 = 100% ✔

➡️ Texture Name: *Silt Clay Loam*
✔ Already given — correct.

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#### b)
- % Clay = 60
- % Sand = 30
- % Silt = 10
- Total = 60 + 30 + 10 = 100% ✔

Now locate:
- 60% clay → left axis
- 30% sand → bottom axis
- 10% silt → right axis

On the triangle, this falls into the CLAY region.

➡️ Texture Name: Clay

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#### c)
- % Clay = ___
- % Sand = 40
- % Silt = 40
- Total = 40 + 40 = 80 → So % Clay = 20%

Now we have:
- Clay = 20%
- Sand = 40%
- Silt = 40%

This matches the ideal loam composition (40% sand, 40% silt, 20% clay).

➡️ Texture Name: Loam

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#### d)
- % Clay = 10
- % Sand = ___
- % Silt = ___
- Texture Name: Loamy Sand

From the triangle, Loamy Sand is found where:
- High sand (>70%), moderate silt, low clay.

But we know:
- Clay = 10%
- Texture is Loamy Sand → typically has:
- Sand ≈ 70–85%
- Silt ≈ 10–25%
- Clay < 15%

Let’s assume typical loamy sand: ~75% sand, ~15% silt, 10% clay.

So:
- Sand = 75%
- Silt = 15%

Check: 75 + 15 + 10 = 100% ✔

➡️ % Sand = 75, % Silt = 15

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#### e)
- % Clay = 45
- % Sand = 10
- % Silt = 45
- Total = 45 + 10 + 45 = 100% ✔

Now find location:
- 45% clay → high clay
- 10% sand → low sand
- 45% silt → medium-high silt

This falls into the CLAY LOAM or SILTY CLAY region?

Let’s look at the triangle:
- If clay > 40%, silt > 40%, sand < 20% → likely Silty Clay

Wait: 45% clay, 45% silt, 10% sand → this is Silty Clay

Because:
- High clay and silt, very low sand → near top center

➡️ Texture Name: Silty Clay

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#### f)
- % Clay = 5
- % Sand = 35
- % Silt = ___
- Total = 5 + 35 = 40 → So % Silt = 65%

Now: Sand = 35%, Silt = 65%, Clay = 5%

High silt, moderate sand, low clay → this is Silt

On the triangle, when silt > 80%, it's silt; here silt is 65%, but still dominant.

Looking at the triangle:
- Silt content: 65%
- Sand: 35%
- Clay: 5%

This falls into the SILT region.

➡️ Texture Name: Silt

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#### g)
- % Clay = 40
- % Sand = ___
- % Silt = 10
- Total = 40 + 10 = 50 → So % Sand = 50%

Now: Sand = 50%, Silt = 10%, Clay = 40%

Check: 50 + 10 + 40 = 100% ✔

Now locate:
- 50% sand → bottom
- 10% silt → right
- 40% clay → left

This is high clay and high sand, low silt → falls in SANDY CLAY or CLAY LOAM?

Actually, from the triangle:
- 40% clay, 50% sand, 10% silt → this is Sandy Clay

Because:
- High sand and clay, very low silt → "Sandy Clay" region

➡️ Texture Name: Sandy Clay

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✔ Final Answers:

| Letter | % Clay | % Sand | % Silt | Texture Name |
|--------|--------|--------|--------|--------------------|
| a) | 30 | 10 | 60 | Silt Clay Loam |
| b) | 60 | 30 | 10 | Clay |
| c) | 20 | 40 | 40 | Loam |
| d) | 10 | 75 | 15 | Loamy Sand |
| e) | 45 | 10 | 45 | Silty Clay |
| f) | 5 | 35 | 65 | Silt |
| g) | 40 | 50 | 10 | Sandy Clay |

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📌 Summary:

- Use the Soil Texture Triangle to plot the percentages.
- Always ensure Sand + Silt + Clay = 100%.
- The triangle divides soils into 12 main types (like Sandy Loam, Silty Clay, etc.).

✔ Best soil for farming: Loam (40% sand, 40% silt, 20% clay) — ideal balance!

Let me know if you'd like a visual guide or how to plot it!