 Soil is the loose material, mostly made of minerals, where plants can grow.  Soil is made of air, water, minerals and organic matter.  Humus is a type of soil that is made up of decayed plants and animals.

 Sand has the largest particle found in the soil.  Sand does not hold water well.  Sand feels gritty and will not form a ball.

 Silt has characteristics between clay and sand ( medium-sized particles).  Silt feels smooth and powdery when dry, and feels slippery when wet.

 Clay feels hard as stone when dry, and feels sticky when wet.  Clay has the smallest particle found in the soil.

 Loam is the best soil for growing plants.  Loam is a mix of clay, sand and silt.

 Topsoil- richest layer (where roots grow)  Subsoil- middle layer  Bedrock-solid rock

 Weathering and Erosion are the two natural processes that change the land.  Weathering-breaking down of rocks into smaller pieces.  Erosion-carrying away of soil and small rocks.  The three forces that change the land are wind, water and ice.

 We need soil in order for plants to grow.  We need plants for food and also to breathe.  We need soil for animals, plants, and humans to survive.