| A | B |
|---|
| Soil | loose, weathered material on Earth's surface |
| Bedrock | solid layer of rock beneath the soil |
| Humus | dark-colored substance that forms as plant and animal remains decay |
| Loam | soil that is made up of equal parts of clay, sand and silt |
| Organic Matter | makes up 6% of loam |
| Topsoil | crumbly, dark brown soil that is a mixture of humus, clay and other minerals |
| A Horizon | develops as plants add organic material to the soil |
| B Horizon | develops as rainwater washes clay and minerals from the other layers |
| Tundra soil | type of soil found where it is cold all year |
| Northern Forest Soil | type of soil found in New Jersey |
| Decomposers | organisms that break the remains of dead organisms into smaller pieces and digest them with chemicals |
| Bacteria | microscopic decomposers that cause decay |
| Air or Water | fill the spaces between the soil particles |
| Earthworms | do most of the work of mixing humus with other materials in soil |
| Natural Resource | anything in the environment that humans use |
| Soil Conservation | the management of soil to prevent its destruction |
| Contour Plowing | slows the runoff of excess rain and prevents it from washing the soil away |
| Conservation Plowing | remains of previous year's crop are left in the ground |
| No Till Plowing | another name for conservation plowing |
| Crop Rotation | different crops are planted in a field each year |
