The material where plants grow and which provides them with physical support, water and nutrients
Soil covers most of the land part of the earth
Different types of soil
Differ in colors, texture, odor and ability to hold water
Some are good for planting while others are not
Types of soil
Clay
Loam
Sand
Clay
Particles are tightly packed together, can hold much water and become sticky when wet, made up of very fine particles of rocks, can be used in making pots
Loam
Mixture of sand and clay, contains a large amount of decaying plants and animals, has a fine texture, can hold enough water and oxygen needed for plant crops
Sand
Particles are coarse and loose, easy to dig, not good for growing plants because it cannot hold water well
Soil is a system into which energy and matter from the sun, atmosphere and living organisms penetrate and interact
Layers of soil
Topsoil
Subsoil
Parent rock
Bedrock
Topsoil
Uppermost layer, rich with organic materials called humus and with minerals needed for plant growth, humus comes from decaying plant and animals, dark color indicates presence of humus, several kinds of plants can be seen growing on this layer
Subsoil
Located just below the topsoil, composed of loosely arranged rock, sand and clay, very rich with minerals that drain from topsoil, cannot support plant life on its own
Parent rock
Composed of rocks that are slowly breaking apart, contains very little weathering, does not contain necessary nutrients and water needed for plant growth
Bedrock
Lowest soil layer, made up of undisturbed large boulders and gravel, contains material good for constructing buildings and making roads, no plant life can survive in this layer
Soil is important because it provides plants with physical support, water and nutrients to grow
