Soil Basics
Functions of Soil
Soil Texture
Soil Color
Soil Horizons
100

What is soil made of?

Tiny rock particles, organic matter, water, and air.

100

Name one function of soil.

(Any of these) Regulating water flow, sustaining life, storing nutrients, supporting structures.

100

Which soil feels gritty?

Sand soil

100

What does a dark soil color usually indicate?

High organic matter content.

100

What is the top layer of soil called?

Horizon O (organic layer).

200

Soil covers the Earth’s surface and supports what?

Plant growth

200

Which function of soil provides structural support?

Providing support to structures.

200

Which soil is smooth and sticky when wet?

Clay soil

200

Red soil color often means the presence of what?

Iron

200

Which horizon is also known as topsoil?

Horizon A.

300

What are the three main soil particle sizes?

Sand, silt, and clay

300

Which function of soil involves storing and cycling nutrients?

Nutrient cycling.

300

Which soil drains more slowly than sand but faster than clay?

Silt soil

300

Grey soils are usually…?

Poorly drained or waterlogged.

300

Which horizon contains clay and minerals washed down?

Horizon B (subsoil)

400

Which type of soil has a balanced mix of sand, silt, and clay?

Loam soil.

400

True or False – Soil helps regulate water flow.

True

400

Which soil property describes how easy soil is to till?

Soil workability

400

What chart is used to classify soil color?

Munsell color chart.

400

What is horizon C made of?

Parent material (broken/weathered rock pieces).

500

How long can it take for one inch of soil to form?

Hundreds to thousands of years.

500

Why is sustaining life above and below ground important?

It maintains ecosystems and food chains.

500

What tool is used to classify soil into 12 textural classes?

Soil Texture Triangle

500

Why is soil color important to scientists and farmers?

It provides clues about fertility, drainage, and composition.

500

Which horizon is solid, unbroken bedrock?

Horizon R.