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Published byMichael Heath Modified over 8 years ago
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Soil
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What is soil? Soil is a mixture of bits of weathered rock, humus, water, and air. Soil is a mixture of bits of weathered rock, humus, water, and air.
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Earthworms, insects, and animals move through soil helping to mix it up and add air and water. Earthworms, insects, and animals move through soil helping to mix it up and add air and water.
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Weather means to wear down, or break apart, rocks. Weather means to wear down, or break apart, rocks. Humus is the decayed matter in soil. Humus is the decayed matter in soil. Humus adds nutrients to soil that are needed for plant growth. Humus adds nutrients to soil that are needed for plant growth.
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Where does soil come from? Soil is produced naturally on earth by weathering. Soil is produced naturally on earth by weathering. It is a natural resource that cannot be quickly replaced. It is a natural resource that cannot be quickly replaced. It can take up to 500 years to make one inch of topsoil. It can take up to 500 years to make one inch of topsoil.
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There are three layers of soil. Topsoil Topsoil Subsoil Subsoil Bedrock Bedrock
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Humus adds the dark color to topsoil.
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What kinds of soil can we find? There are three main types of soil: There are three main types of soil: Clay soil Clay soil Sandy soil Sandy soil Loam Loam
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Clay Soil Clay soil holds water very well. Clay soil holds water very well. The bits of weathered rock are very small. The bits of weathered rock are very small. It is a tightly packed soil. It is a tightly packed soil. Most plants don’t grow well in clay soil because it stays too wet and roots can’t push through it easily. Most plants don’t grow well in clay soil because it stays too wet and roots can’t push through it easily.
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Sandy Soil Sandy soil has large, loosely packed grains. Sandy soil has large, loosely packed grains. Sandy soil doesn’t hold water well. Sandy soil doesn’t hold water well. Plants don’t grow well in sandy soil because nutrients pass through quickly with water. Plants don’t grow well in sandy soil because nutrients pass through quickly with water.
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Loam Loam is a mixture of clay, sand, and humus. Loam is a mixture of clay, sand, and humus. Loam is good for plants because Loam is good for plants because Roots can push through easily Roots can push through easily It has nutrients from the humus It has nutrients from the humus and it holds just the right amount of water and it holds just the right amount of water
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All living things depend upon plants as producers of energy. All living things depend upon plants as producers of energy. All plants depend upon soil to: All plants depend upon soil to: Hold roots in place Hold roots in place Hold nutrients for roots to absorb Hold nutrients for roots to absorb Hold minerals (from weathered rock) for roots to absorb Hold minerals (from weathered rock) for roots to absorb
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We need to conserve, or save and protect, the topsoil for plants to grow in.
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How can soil be conserved? To keep topsoil in place we need to prevent erosion. To keep topsoil in place we need to prevent erosion. Erosion is the movement of soil or rocks by wind or water. Erosion is the movement of soil or rocks by wind or water.
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Erosion can move topsoil to new places. Erosion can move topsoil to new places. To stop erosion we can- To stop erosion we can- Plant grass, shrubs, and trees because the roots help hold soil in place. Plant grass, shrubs, and trees because the roots help hold soil in place. Plant trees as wind blocks. Plant trees as wind blocks. Use contour plowing across hills rather than up and down. Use contour plowing across hills rather than up and down.
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Contour Plowing
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Water Erosion
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Wind Erosion
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Planting wind breaks to stop wind erosion.
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What can weather rock? Plant roots can weather rocks, breaking them down into smaller pieces. Plant roots can weather rocks, breaking them down into smaller pieces. Water freezing in cracks of rocks can cause rocks to weather. Water freezing in cracks of rocks can cause rocks to weather.
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How can nutrients be put back into soil? Nutrients can be put back into soil by- Nutrients can be put back into soil by- Planting different crops Planting different crops Adding fertilizer Adding fertilizer Adding humus Adding humus Adding compost Adding compost Mulching around plants Mulching around plants
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Select a spot for your bin.
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Compost Ingredients Air Air Water Water Brown stuff – dead leaves, dried plant parts Brown stuff – dead leaves, dried plant parts Green stuff – grass clippings, weeds, kitchen scraps Green stuff – grass clippings, weeds, kitchen scraps
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What should NOT be put into compost? Meat or milk products Meat or milk products Diseased plant parts Diseased plant parts Bones Bones Cheese Cheese Pet waste Pet waste
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Build your compost in layers starting with about 6 inches of brown stuff.
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Next, add green stuff like grass clippings. It’s best to mix it a little.
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Sprinkle a shovel full of soil or compost on top to add microorganisms to the bin.
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Water each layer of the compost material. Repeat until the bin if full.
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Now the microorganisms can go to work breaking down the organic matter into compost. Now the microorganisms can go to work breaking down the organic matter into compost. Later, once the compost cools down you may see larger organisms like sowbugs, millipedes, and earthworms. Later, once the compost cools down you may see larger organisms like sowbugs, millipedes, and earthworms.
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Microorganisms - Decomposers
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This is dark, earthy-smelling compost. It is rich in nutrients for plants.
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You can use compost to mulch around plants. The nutrients get washed into the soil from rain.
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Compost is great for mixing into the soil when planting new plants. It improves both sandy and clay soils.
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What are some ways we harm our soil? We harm our soil when we use too many fertilizers and pest killers. We harm our soil when we use too many fertilizers and pest killers. These chemicals can also get into our water supply and cause water pollution. These chemicals can also get into our water supply and cause water pollution. When we remove too many trees and plants to build roads and buildings, we can cause serious erosion problems. When we remove too many trees and plants to build roads and buildings, we can cause serious erosion problems.
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Conserve our soil – A precious natural resource!
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