| A | B |
|---|
| Soil | mixture of rock particles, minerals, organic material, water, and air |
| bedrock | the solid layer of rock beneath the soil |
| humus | decayed organic mater in soil. Dark color. |
| fertility | measure of how well soil supports plant growth |
| loam | equal mixture of clay, sand, and silt |
| soil horizon | layer of soil that differs in color and texture from the later above or below |
| topsoil | dark brown soil, mixture of humus, clay and minerals |
| subsoil | clay and other particles washed down from other A horizon little humus |
| litter | Loose layer of leaves and plants on top of soil |
