Soil ManagementSite Selection, Soil Fertility
Warren RobertsGeorge Kuepper
Where We’re Going• Soil Texture and Drainage• Site Selection• Soil Fertility & pH
• Fertilizers & Nutrients
Later Sessions• Soil Biology & Micro-Organisms
• Compost, Cover Crops and Green Manures
• Organic Farming
Commonly Known Soil Types• Sandy, Sandy Loam, Loam
• Light Soil (Not Really)
• Clay• Heavy Soil (Not Really)
• Sandy Soils are Actually Heavy• Clay Soils are Actually Light
An Acre of Soil Weighs What?
• Acre furrow slice• Top plow layer over one acre• Usually 6-7 inches deep• Averages about 2 million lbs
Definitions
• Clay (0.001 – 0.002 mm)• Silt (0.002 - 0.050 mm)• Sand (0.050 - 2.00 mm)• Gravel (>2.00 mm)
Pore Space• The portion of the soil volume occupied by
air and water
• Ideally half air and half water
• Very Important for Plant Growth
Pore Space• Macro Pore (Large Spaces)
• Sands• Micro Pore (Small Spaces)
• Clay
Water Movement in Soil
• Gravity• Primary force in sandy soils
• (large pores)
• Capillary Forces, Osmotic (Suction)• Primary force in clay soils
• (small pores)
Soil Moisture
• Saturation• All pores filled
• Can become Anaerobic
• Field Capacity• Drainage has ceased• Capillary action holds remaining water• Micro-pores may be full
Ideal Soil• Most Desirable
• Loam• Sandy Loam• Loamy Sand• Sandy Clay Loam
• Least Desirable• Sand
• Won’t hold water• Clay
• Difficult to work
Ideal Soil• Well Drained Area
• Not in a flood plain• Not in a low-lying area where water can accumulate
• Good air drainage• Not subject to late spring frosts or early fall frosts
• Deep Soil• Not overlying a rocky base• Not overlying a clay base
Ideal Organic Soil• Not Contaminated from Previous Years • Not Contaminated by Neighbors• Not Contaminated by Highways, Power Line
Right-of-Ways
Ideal Soil• Easy to Access• Easy to Irrigate• Easy to Control Predators
• Deer, Raccoons, Feral Hogs, Coyotes, Humans
Organic Matter – For Whatever the Reason
• Holds Water• Prevents Excess
Drying
• Improves Drainage• Prevents Saturation• Keeps Soil Aerobic
• Prevents Runoff
• Like a Sponge
Organic Matter – For Whatever the Reason
• Holds Nutrients• Prevents Nutrient
Loss• Prevents
Environmental Contamination
Organic Matter – For Whatever the Reason
• Improves Tilth• Provides Larger
Pore Spaces for Root Growth
• Allows for Air-Water Movement
Ideal Soil
• 50% Solid Matter• 45% Mineral• 5% Organic
• 50% Pore Space• 25% Water• 25% Air
Soil Fertility
• Supplies Nutrients to the Plant for Growth and Development
Soil Fertility• Essential Plant Nutrients
• 16 (18) required for plant growth, development, and reproduction
• Macronutrients: (large quantities used by the plant)
• Micronutrients: (small quantities used by the plant )
Soil Fertility – Macro Nutrients
• Primary
• Secondary
• Carbon ( C )• Hydrogen ( H ) • Oxygen ( O )
• Nitrogen ( N )• Phosphorus ( P )• Potassium ( K ) Kalium
• Calcium (Ca)• Magnesium ( Mg)• Sulfur (S )
Soil Fertility
Micro Iron ( Fe )Boron ( B )Copper ( Cu)Chlorine ( Cl )Manganese ( Mn )Molybdenum ( Mo)Zinc ( Zn )Cobalt ( Co )Nickel ( Ni )
Soil Fertility
• See Hopkins Cafe. • Managed by My Cousin, Colonel Mo Cleaver
Soil Fertility• See Hopkins Cafe. Managed by My Cousin,
Colonel Mo Cleaver.
• C H O P K N S • Ca Fe
• Mg Bo Mn Cu Zn• Co Mo Cl• Ni
pH
• Definition: Inverse Concentration of Hydrogen Ion Concentration, Expressed in Moles per Liter
• Practical Definition: Amount of Acid in the Soil• pH goes up as H+ concentration goes down
• VERY Important, but Often Overlooked
Typical Fertilizer• 5-10-15• 13-13-13• 34-0-0• 18-46-0• 0-0-62• 0-46-0
