Soil Composition and Properties

This video tutorial explains how to use a soil texture diagram, also known as a soil triangle, to determine the composition of soil samples in terms of sand, silt, and clay percentages. The instructor walks through several examples, demonstrating how to identify soil types such as sandy loam, silt, clay loam, silt loam, and clay. The video also discusses the properties of different soil types, including nutrient retention, permeability, and workability.

What is the primary purpose of a soil texture diagram?

• To identify the percentage of sand, silt, and clay in soil

• To measure soil temperature

• To calculate soil pH levels

• To determine the color of soil

In the first example, what is the texture name for a soil with 75% sand, 10% silt, and 15% clay?

• Clay Loam

• Sandy Loam

• Silt Loam

• Loamy Sand

When using a soil texture diagram, which line should you follow to determine the percentage of sand?

• The line on the right

• The diagonal line

• The line on the left

• The middle line

What is the nutrient holding capacity of silt as described in the second example?

• Very High

• High

• Medium

• Low

In the third example, what is the calculated percentage of silt if the soil has 42% sand and 37% clay?

• 35%

• 21%

• 25%

• 30%

What property of clay makes it good for nutrient retention?

• Its high permeability

• Its negative charge

• Its positive charge

• Its large pore spaces

In the fourth example, what is the texture name for a soil with 21% sand, 52% silt, and 27% clay?

• Sandy Loam

• Clay Loam

• Silt Loam

• Loamy Sand

Which soil component is described as having high permeability due to large grains?

• Clay

• Silt

• Sand

• Loam

In the fifth example, what is the percentage of sand if the soil has 35% silt and 50% clay?

• 15%

• 25%

• 10%

• 20%

What is the main disadvantage of clay in terms of workability?

• High permeability

• Low nutrient retention

• Small pore spaces

• High nutrient leaching