Every soil has different amounts of sand and silt and clay. The mix of sand and silt and clay is the "texture" of the soil. We can also say the mix has a "soil texture". A soil with a lot of sand is called a "sandy soil texture". A soil with a lot of silt is called a "silt soil texture". A soil with a lot of clay is called a "clay soil texture". Farmers like to grow food in the best soil. The best soil is half sand and some silt and a little clay. The organic matter found in the soil is not counted in the soil texture. Only the rocks are counted when we discover the soil texture. Soil texture is very important.
Clay and humus are special parts of the soil. They help keep water and plant food (plant nutrients) in the soil. Water and plant nutrients stick to clay and humus. Water sticks to all of the rock in the soil. But water sticks best to clay. Water is taken into (absorbed) into humus like a sponge absorbs water. Humus holds a lot of water and plant nutrients.

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