Soil and Nutrients

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Soil and Nutrients
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How is soil formed?

• Interaction of 5 factors
• Rocks
• Sunlight
• Water
• Air
• Living organisms
• What determines the RATE of soil formation?
• climate
• What determines the TYPE of soil formed?
• material and precipitation

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Weathering Agents

• Chemical and physical forces that break apart
  rocks or remove minerals
• Temp changes
• Water/ice
• Tree/plant roots
• Sand and rocks
• Glaciers
• Wind

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Look at your sample

• What percentage of clay, silt, sand do you
  estimate?
• How does that help you determine your soil type?

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Particle Size Soil Texture SAND, SILT, CLAY
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Particle Size Soil Texture SAND, SILT, CLAY

• What type of soil do we have?
• What type of soil do we want?

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SAND, SILT, CLAY, HUMUS

• Why dont plants grow well in soil high in clay
  or sand content?
• Whats the best use for land with muck soil
• Housing development or farm specializing in
  vegetables? Why?

Soil Texture Infiltration Water Holding Capacity Aeration
SAND Good Poor Good
SILT Medium Medium Medium
CLAY Poor Good Poor
LOAM Medium Medium Medium
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Soil and Nutrients

• 3 Primary nutrients?
• N, P, K
• why do we need them?
• Limiting factor vs. poisoning
• Proper pH Levels
• Allow for chemical absorption

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• Nitrogen
• Growth of leaves stems
• Green v yellow
• Fungus danger

• Potassium
• Strong stems
• Ripen fruit
• Disease danger
• Brown edges

• Phosphorus
• Good root growth
• Flower seed formation
• Disease danger
• purple

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Soil Layers in ground
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The Nitrogen Cycle
The air is 78 nitrogen, why cant organisms use
this? What role do bacteria play in the nitrogen
cycle?
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The Phosphorus Cycle
Takes hundreds of millions of years to complete
cycle Sources Guano, erosion of rock, ocean
sediment
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Fertilizer Solutions
Advantages Disadvantages
SYNTHETIC
ORGANIC
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Fertilizer Solutions
Advantages Disadvantages
SYNTHETIC Less needed Known nutrients quick Harmful concentration Easily leached
ORGANIC Not as harmful Stay longer Add humus More needed Variable nutrient amts