Unit C
Chapter Three
Soils| soil | the loose material in which plants can grow in the upper layer of the Earth |
| humus | the part of soil made up of decayed parts of once-living things |
| topsoil | the top layer of soil |
| bedrock | the solid rock that is underneath the soil |
| clay | has many grains and small spaces between the grains |
| laom |
rich soil with a lot of humus |
| resource | material found in nature that living things use |
| conservation | saving resources by using them carefully |
| strip cropping | planting strips of grass between crops |
| contour plowing | planting crops around a hillside instead of up and down |