1. Soil Formation and Composition EQ: How do you scientifically describe soil? How is soil formed?

2. Soil Formation Soil- the loose, weathered material on Earth’s surface in which plants can grow Three parts to soil formation Begins as bedrock- solid layer of rock beneath the soil Broken down by weathering Mixes with other materials on the surface EQ: How do you scientifically describe soil? How is soil formed?

3. Soil Composition Soil – a mixture of rock particles, minerals, decayed organic material, air and water Rock particles and minerals are sand, silt and clay Two factors affect the rock particles and minerals found in a soil - original type of bedrock - type of weathering EQ: How do you scientifically describe soil? How is soil formed?

4. Soil Composition Humus – dark colored substance that forms as plant and animal remains decay – Creates space in soil for air and water – Rich in nutrients plants need to grow: nitrogen, sulfur, phosphorus, and potassium sepup EQ: How do you scientifically describe soil? How is soil formed?

5. Soil Texture Defined and described by the size of the particles. Rubbing soil between your fingers tests the soil’s texture. Different names are given to soils depending on the proportion of sand, silt, and clay. Every soil on earth is defined as sand, silt, clay. EQ: How do you scientifically describe soil? How is soil formed?

6. Soil Texture All particles as large or larger than pebbles or gravel (diameter greater than 2 mm) are not considered soil, although they will often be found in it. EQ: How do you scientifically describe soil? How is soil formed?

7. Soil Texture is: grainy if the soil is made up of large-sized pieces and feels gritty, like sand. silky if the soil is made of medium-sized pieces and feels powdery, like silt. sticky if the soil is made of small pieces and feels gummy, like wet clay. EQ: How do you scientifically describe soil? How is soil formed?

8. Rate of Soil Formation Depends on the climate and type of rock – Warm and rainy climate – soil will develop quickly – Cold and dry climate – soil will develop slowly EQ: How do you scientifically describe soil? How is soil formed?

9. Soil Horizons A layer of soil that differs in color and texture from the layers above or below it EQ: How do you scientifically describe soil? How is soil formed?

10. Life in soil- organisms mix the soil, create space for air and water make hummus Plant “litter”, a loose layer over the soil where plants shed leaves or die Decomposers, organisms that break down the remains of dead plants and animals live in the soil Bacteria, fungi, earthworms, snails and beetles EQ: How do you scientifically describe soil? How is soil formed?

11. Soil Types in the United States Scientists classify soil into different groups based on several factors – Climate – Common plants found in the region – Soil composition EQ: How do you scientifically describe soil? How is soil formed?

12. Class Work and Homework Fill In – What did I learn – Confused – Say Describing Soil Scientifically Mapping US Soils