When we moved to 100% notill in 2003 we had to obtain a notill
fertilizer applicator to be used for pre-plant and topdress application
on wheat and topdress application on alfalfa ground. After much research
on toolbar and opener designs and product delivery systems we opted to go
with a DMI (now owned by Case IH) 2800 Nutri-placr. This rig was designed
for fertilizing corn and thus needed some modifications. First, we added
to small extensions on the wings to achieve a true 40' working width. Additional
openers were added so that we have 32 openers on 15" centers. This
is a direct-injection setup where a rolling coulter opens a 1/4" slot
up to four inches deep and then a trailing nozzle injects fertilizer in
this slot at between 20-80 psi. Setup in this manner, the fertilizer rig
is very low disturbance and causes very minimal damage when operated in
a growing wheat crop.
The potential downsides to a direct-injection machine are
fertilizer "splash" which occurs under high pressure situations
and involves the stream of fertilizer striking the bottom of the slot at
such pressure that part of it "splashes" back out of the slot
and nozzle misalignment. A 1/4" slot can be a challenging target to
hit, especially in heavy residue fields and a slight misalignment of the
nozzle in relation to the slot results in putting the fertilizer on top
of the ground rather than in the slot where it needs to be. This is especially
a problem when fertilizing on corn stalk ground as corn stalks have a way
of getting wedged in anything. If everything is maintained correctly, this
is not a significant determinant to the system, however diligence is needed
in the field to ensure constant and proper nozzle alignment
For fertilizer delivery, we really wanted the ability to variably
apply two liquid products simultaneously. Consequently, we went with dual
systems each consisting of a Hypro 9303 HM4C hydraulic centrifugal pump,
a pulse-width modulating valve for controlling the pump, a Raven flow meter
and a Raven pressure transducer. Each side of the system is controlled by
a Raven 440 controller that is in turn controlled by Farmworks SiteMate
VRA running on an Ipaq. Site-specific prescriptions are designed in the
office and then moved to SiteMate VRA which completely takes control over
the system when in the field.
We pull this rig with our John Deere 8420 tractor (with Auto-Trac)
and average around 11 mph in the field. We place up to 1300 gallons of 32-0-0
(nitrogen product) in the toolbar mounted tank and then up to 1000 gallons
of 10-34-0 (phosphorus product) in a 1000 gallon JD
Skiles pull behind trailer. Tendering is accomplished using our 1992
Freightliner pulling a 42' flatbed trailer that was setup for delivering
fertilizer. This trailer can carry around 4000 gallons of product in three
separate compartments. A two-inch plumbing system delivers the liquid fertilizer
through a 30' hose to the fertilizer rigs tanks.
This picture shows our setup for testing a Flexi-Coil fertilizer opener.
Here is the DMI 40' rig in the field topdressing wheat in corn stalks
in 2006. It is being pulled by our John Deere 8420 with Auto-Trac.
Here is the DMI rig folded up for transport. In this picture one can also
see the 1000 gallon pull-behind tank used to carry one of the liquid products.
View of valving system. On the right side the Hypro pump can be clearly
seen on the toolbar frame and another is setup on the exact opposite side.
Both pumps move product through the valving systems and then through a
one-way valve into a common manifold where they are then blended. From
the manifold, the blended product is then delivered to the openers.
The fertilizer opener is shown here. The rolling coulter is 15" in
diameter and runs straight (as opposed to pitched). The hose delivering
the fertilizer is shown attached to the tube that contains the nozzle.
We added the big bolts behind nozzle bodies to prevent the nozzles from
being forced backwards by residue (which causes the fertilizer stream
to become misaligned with the slot). The design of this opener allows
us to apply fertilizer subsurface while disturbing only a minimum amount
of residue and soil structure.
Here is a picture of the in-cab components. On the bottom left are the
two Raven 440 controllers, each controlling one of the two liquid delivery
systems. In the upper right the two RAM mounts are shown that hold the
Ipaq's. At this point in time (2002), we were not running Auto-Trac on
this tractor yet, hence the absence of the GreenStar I console.
Here is a close up view of the two Ipaq's running Farmworks SiteMate VRA.
The wires coming into the top of the Ipaq's provide GPS signal (from the
tractors' Starfire receiver) while the two big cables coming out of the
bottom of the Ipaq's are connected to the Raven 440's. If you look closely
at the field shown on each Ipaq different colors can be seen across each
map which represent different fertilizer rates. SiteMateVRA plots the
GPS signal from the tractor when moving and as the location of the tractor
moves from one-acre grid to one-acre grid the applicable rate is automatically
"looked up" in the prescription map and then sent to the Raven
Here is a picture from the wheat topdressing application in 2005. Notice
the presence of the GreenStar I console (running the Auto-Trac) as well
as the absence of one of the Raven 440 controllers. At this application,
we are typically only applying one product (32-0-0) and consequently don't
need the second product delivery system. Also in this picture a GreenSeeker
handheld system can be seen (yellow pole attached to square box on floor).
We were collecting data with the GreenSeeker during this operation which
was then logged on the second Ipaq shown in the picture. The GreenSeeker
sensor was mounted on the weight bracket of the tractor.
The DMI Nutri-placr has been an extremely reliable and durable rig, especially
when one considers that the majority of the time it is being pulled at
11 mph, over the tops of terraces, and typically carrying over 1500 gallons
of product. We are pleased with its low residue and soil disturbance characteristics,
its narrow transport width (14.7') and it's low horsepower requirements.
My only complaint is that it is only 40' instead of 60 or 80'. At 11 mph
and the 40' width, we can cover over 50 acres per hour. With tendering
and transport between fields included, we average around 30 acres per
Fertilizing in standing stripper cut wheat stubble. Also shown is our
new (in 2008) JD Skiles Row-tracker trailer that has two tanks (500/1300).
Showing full "train" in the field with row-tracker trailer in
Today we no longer use the Raven 440's and have converted everything over
to be run by an AgLeader Insight.
At 40' this rig is on the small end of what we need and we are searching
for at least a 60' rig to replace this one. So far we haven't found anything
we really like so it may be necessary to build our own.