III. Fertilizers: Utilization and Types. Introduction World demand for increased food, feed, and...
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Transcript of III. Fertilizers: Utilization and Types. Introduction World demand for increased food, feed, and...
III. Fertilizers: Utilization and Types
Introduction
World demand for increased food, feed, and fiber production necessitates us of fertilizers.
Fertilizers
Fertilizers are materials occurring naturally or commercially produced for application to soil for the purpose of adding one or more deficient nutrients
Fertilizers
Research says that optimum ferts use increase yields world wide by 50%
Fertilizer History
Farmers used ferts lavishly before 1974.After 74, fuel and energy cost
skyrocketed!Farmers needed more money, so they
selected soil and crops that used ferts the best.
But bottom line, fert does not cost, it pay!
Fertilizer Trends and Economics
Dry bagged fert use decreased with the increase use of dry-mix and liquid fert.
Fertilizer Trends and Economics
Ferts cost represent about 20% of all crop productions
Producers expect a corresponding increase in yield of 50%
This is a return of two to three dollars for every dollar spent
Fert is Profitable When:
1. Based on a soil test2. Added in an
efficient manner3. Soil is managed
Fert is Unprofitable When:
1. Soil moisture is limited
2. Pest and adverse temps are a problem
3. Increased yield has less market value than cost of ferts.
Fertilizer Efficiency
Point of Diminishing Return
Point at which cost of applying additional fert is unprofitable in terms of increased production
Determining Fertilizer Needs
Amount and Type depends on:– 1. Amount removed by previous crop– 2. Amount lost by leaching and other
processes– 3. Amount and type of nutrients available in
soil– 4. Climatic conditons– 5. Requirements of present crop– 6. Crop quality desired
Determining Fertilizer Needs
Just do a soil test analysis! Idiot!
Types of Ferts.
1. Organic Derived from plant and
animal material
2. Inorganic Contains no C, H, and
O’s
Forms of Fertilizer Materials
1. Dry-MixMade by combining selected elements into a bulk blendcomes in a granular form
2. LiquidMaterial completely dissolved in solutionMay contain a single nutrient or mixture
3. GaseousAnhydrous ammonia
Numbers on the Bag
Types of Fertilizers
Nitrogen– N
Phosphorus– P
Potassium– K
Fert Grade and Quality Control
Label must contain:– Weight of material– Manufacturer’s name– Manufacturer’s address
Fert Grade and Quality Control
Example: 10-20-10Contains 10% Nitrogen, 20% P2O5,
and 10% K2060% of the product is conditioners
(to reduce caking), acidity neutralizers (Lime), fillers (extender added to improve uniform distribution of nutrients
Nitrogen Ferts
Material
1. Ammonium nitrate
2. Ammonium sulfate
3. Anhydrous ammonia
4. Aqua ammonia
5. Organic products
6. Urea
Nitrogen Content (N%)
33.5%
20 – 21 %
82%
20-24%
1-12%
45-46%
1. Ammonium Nitrate
NH4NO3
50% is ammonium form and the remainder is in nitrate form.
The two allow nitrogen to be used immediately
2. Ammonium sulfate
(NH4)2SO4
High in costBest forms of N for rice crops
3. Anhydrous ammonia
NH3, is the principle nitrogen fert.
Applied by injection into moist soil behind tractor at about 6 inches deep.
Made from atmospheric nitrogen and natural gas in Texas plants.
4. Aqua ammonia
NH3 + H20
A low pressure nitrogen fert, applied three inches below soil surface.
5. Organic products
Sludge, Manure, Meat Meal, Cottonseed Meal, and fish meal.
6. Urea
A controlled release fert.Formed by coating granular urea with
sulfur, then wax, then clay.
Phosphorus Ferts.
Material
1. Basic Slag
2. Bone Phosphate
3. Rock Phosphate
4. Superphosphate, ordinary
5. Superphosphate, triple
Multiple P% by 2.29137 to obtain P2O5% equivalent.
Phosphorus Content (P%)
3.5 – 5.2
10-13
13-17
9
20-22
1. Basic Slag
Low-phosphorous by-product of iron and steel mills
Used mainly in areas where produced
2. Bone phosphate
Steamed bone mealOldest known phosphate fertilizer
3. Rock phosphate
Mainly from Florida
4&5. Superphosphate
Rock phosphate mixed with sulfuric acid = superphosphate
Rock phosphate mixed with phosphoric acid = triple superphosphate
Potassium Ferts
Material1. Muriate of potash2. Sulfate of potash3. Sulfate of potash
magnesia4. Potassium nitrate5. Potassium
polyphosphate
Multiply K% by 1.20459 to obtain K2O% equivalent
Potassium Content (K%)
42-50
37-42
15-18
31-37
17-33
Ferts supplying other nutrients
Lime
Sulfur
Boron
Molybdenum
Iron
Zinc
Magnesium
The End