Methods of Applying Fertilizer
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Transcript Methods of Applying Fertilizer
Methods of Applying Fertilizer
Chapter
7
What to consider when selecting an
application method.
Rooting characteristic of the crop to be
planted.
Crop demand for various nutrients at
different stages of growth.
Physical & chemical characteristics of the
soil.
Physical & chemical characteristics of the
fertilizer material to be applied.
Availability of moisture.
Type of irrigation system used if irrigation
is the only, or major, source of water.
Frequency and rate of irrigation water to be
applied.
Pre-Plant Applications
Broadcast – distributing over the top of
the soil.
Dry
or liquid form.
May
be mechanically worked into the soil
or incorporated by rainfall or irrigation.
Drop Spreader
Simple Fertilizer spreader – inverted
triangle-shaped hopper mounted between
two wheels.
= small hopper size limits the load capacity
& field size it can be used on.
-’s
+’s
= small size lends itself well to vineyards
and orchards.
Spinning-disc spreader
A small bulk spreader pulled by a tractor or
truck.
Uses horizontal spinning disc to broadcast
fertilizer.
20’ – 40’ swath
-’s
easy to have skips or overlaps of fertilizer.
Self-propelled spreader
A large bin mounted on a large truck or a
special 3 or 4 wheel vehicle equipped with
floatation tires ( reduce soil compaction)
Can have simple horizontal-spinning-disc to
air-flow applications
Air-flow applicators have the capability to
apply more than one fertilizer material at
the same time.
Liquid Spreader
Liquid Spreader
Tank, Pressure gauge, Regulator, Pump,
Pipes, Hoses, Fittings, Nozzles, and a boom.
Can be mounted on a truck, on a flotation
vehicle or trailer, or directly on a tractor
Organic Spreaders
Similar to a spinning disc spreader.
Normal to apply 5 – 20 tons per acre.
Poultry waste is at a lower rate.
Pre-Plant Applications - Injection
Injection refers to placing fertilizers
below to soil surface.
All fertilizer that can be broadcasted on
the soil can also be injected.
How does injection take place?
Drop pipes for liquids.
Flexible tubes for dries.
Channels are made by knives or shank openers
mounted to the tool bar.
This is best done after the soil has been plowed,
disced or furrowed out and the soil is loose.
Advantages of injections.
Eliminates N gaseous losses.
Reduces fertilizer losses caused by rain or
wind erosion.
Places the fertilizer directly in the root zone.
Disadvantages of injection.
Power requirements are greater.
Some specialized equipment is required for
some types of fertilizer. (Anhydrous
ammonia)
May disrupt the integrity of the beds.
Liquids are harder to apply than dry.
Applications at Planting
Subsurface Banding (pop-up application)
Appling fertilizer directly with the seed.
Grain crops do well with this.
Note** use low rates of starter fertilizers
Look at chart 7-1 found on page 168.
Surface Banding
Liquid fertilizers being applied to the soil
surface directly above the seed.
Sprinkler or rainfall need to move fertilizer
down.
Also used as an anti-crust. (acid serves to
dissolve calcium carbonate crusts that
impede crop emergence.)
Post-Emergence Application
Sidedressing – refers to placement of
fertilizer beside crop rows & may be
combined with cultivation.
Both liquid and dry can be used.
Topdressing
Appling fertilizer to the soil surface after
the crop emergence.
The same equipment is used in the pre-
plant broadcast applications
Water-Run Application
Savings in time, labor, equipment, & fuel
cost.
May be pre-plant or post-emergence.
Disadvantage to this type of application is
uniformity of distribution and run-off water
containing fertilizer.
Irrigation – Open Systems
Ditches (lined or unlined)
Gated pipe (used for furrow or flood
irrigation)
Both dry & liquid fertilizers can be used.
Irrigation – Open Systems
High-pressure center pivot, linear, and
solid-set sprinkler systems.
Low pressure drip, mist, & micro-sprinkler
irrigation systems.
Not all dry & liquid fertilizers are suitable
for application in closed systems.
Examples
Aqua ammonia & anhydrous ammonia due
to the precipitates that may be formed if
irrigation water high in calcium content.
Plugging is a main problem in low pressure
systems.
Foliar Application
Supplying nutrients during periods of peak
demand when an immediate response is
desired.
Supplying certain nutrients, such as zinc,
when soil or crop conditions are conductive
to root uptake.
Allowing precise timing of nutrient
application related to the quality
characteristics of the crop being grown.
Reducing nitrate leaching in certain
cropping systems.
Providing a source of nutrients to satisfy
crop demand temporarily until a soil
application can be made.
Factors that may improve the
effectiveness of foliar nutrient.
Application during early morning or
evening hours.
Application when temps. Are less than 850F.
Relative humidity greater than 70%
Inclusion of a high quality adjuvant.
(increases its effectiveness)
Cont.
Wind speed less than 5 miles per hour
Application to young, actively growing
tissue as compared to older, harden-off
tissue.
Application to expanding buds in perennial
woody crops.
Calibration of Application Equipment.
Look at tables 7-3, 7-4, & 7-5.