What's in the soil?

The soil is make up of physical, chemical and biological properties. The physical part of the soil is the sand, silt and clay in different proportions. The chemical part of the soil is the minerals like calcium and selenium for example. The biological part of the soil is the micro-organisms and they are ALIVE. When we use pesticide, these chemicals kill the part of the soil that is alive. This is one reason organic practices are so important.