1. Variable Rate Fertilizer:
Ways to Increase Profitability
Prepared for:
ACSM 305 Class
The Ohio State University
Columbus, Ohio 43210
Prepared by:
Andrew McChesney
Chris McChesney
Calen Schamp
David Schulte
Ohio State University
Columbus, OH 43210
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2. McChesney, Schamp and Schulte
Consulting
305 classmates/The Ohio State University
Dept. of Food, Agricultural and Biological Engineering
590 Woody Hayes Dr.
Columbus, OH 43210
Dear Mrs. Britt:
Here you will find the report you requested including information on the feasibility of the use of
variable rate fertilizer technology in today’s world and our recommendations for the use.
During the analysis, our team considered and researched the technology of variable rate
fertilizer use on individual farms. We searched for various things including the history, the
initial costs of equipment, time it will take to pay off, the benefits of reducing over application,
and the pros and cons. Our findings show that the use of variable rate application of fertilizer
would benefit farms by saving money on the price of fertilizer, and yield gain, and we
recommend the use on individual farms to boost productivity.
There is already many other farmers advancing their operation and we feel it is time to the
same. With the technology available, it is easy to see the potential profit that is possible to be
made.
The analysis of this report came from several helpful sources. We found most of our
information online from various agriculture related websites.
Thank you for allowing us to conduct this research. We have learned a lot about the
opportunities available with the technology of variable rate fertilizer. If you have any questions
we would be glad to help you. We look forward to working with you.
Sincerely,
David Schulte
Team Leader
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3. Table of Contents
Cover Page………………………………………………………………………………....
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Letter of Transmittal……………………………………………………………………….
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Table of Contents…………………………………………………………………………..
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Executive Summary………………………………………………………………………..
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Introduction…………………………………………………………………………………
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Purpose and Scope…………………………………………………………….……
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Limitations………………………………………………………………………..…
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History……………………………………………………………………………………....
Body…………………………………………………………………………………….….
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Conclusion………………………………………………………………………………………………..……
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References…………………………………………………………………………………………………..…
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4. Variable Rate Dry Fertilizer
Applying Variable Rate Fertilizer to Your Farm
Executive Summary
To keep up with rising land cost, equipment, and fertilizer cost every farmer should use variable
rate technology in their crop rotation. Variable rate technology is on the cutting edge of the
agriculture industry, the time and money saved greatly benefits today’s larger scale grain farms.
Our research shows that using variable technology will be more profitable for grain farmers for
several reasons. First, you are using only the fertilizer that is needed for a certain piece of
ground and not wasting money by over applying. Second, being more precise with fertilizer
application you are getting all the nutrients to your plants that they need and not over applying
which over time, can build up in the soil and potentially be harmful to future crops.
To insure success in today’s ever changing agriculture our group recommends the following:
1. Incorporate variable rate technology on your farm.
This will boost crop production
Variable rate technology will lower your cost per acre
Using this technology will not allow for harmful build ups in your soil
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5. Introduction
Purpose and Scope:
Farmers are a very competitive group of people. To remain competitive within the rapidly
growing United States’ agricultural business, farmers need to cut back their input costs. The
purpose of this research is to determine if and to what extent farmers should purchase and use
the technology of variable rate fertilizer.
This report will cover several topics about fertilizer technology including the history, the initial
costs of equipment, time it will take to pay off, the benefits of reducing over application, and
the pros and cons of variable rate fertilizer.
Limitations:
This research was limited to materials available through the internet. In addition, all four of us
are majoring in Agricultural Systems Management at The Ohio State University. However,
Andrew and Chris are the only ones with experience with the technology first-hand. Although
time constraints and scheduling conflicts have limited our time to work on the project to inclass we split the projects into separate even portions so we could go off on our own and come
together with the work we completed. Our group presentation could be benefited if we would
have had the access to have an open field to display how to setup and use the equipment.
History:
The method of variable rate fertilizer application has been around for a long time. The original
thought of variable rate application was thought of as visually looking at fields and taking soil
samples of the deprived looking areas of the field. Processing these soil samples allowed the
farmer to apply the nutrients needed in only the areas needed. Today, the technology of GPS
and computers are rapidly replacing the old ways of counting rows or looking for non-typical
areas. Along with GPS and computers, new technology such as yield monitors and aerial
photography have greatly increased the awareness of fertilizer deficiency (Fasching, 2011).
The lack of advancements in variable rate technology can be linked to the price of fertilizer.
When this technology was originally released in the mid 1990’s, it never caught on with the
farmers. This is because the price of fertilizer was so cheap and the equipment was so
expensive, people could afford to buy enough to apply to the entire field rather than only the
areas of need (Reetz, 2012).
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6. Equipment
The equipment used to variable rate products can be both expensive and the
technology that you use can be intimidating, but in today’s agriculture industry you are
probably already using part of the system on the farm today in your planting tractor or sprayer.
Variable rate systems have been around for over ten years now and as time has gone by the
equipment has gotten less expensive and more user friendly to make it possible for a typical
farmer with basic computer skills to be able to put these time and money saving practices to
work.
Soil Sampler
There isn’t one piece of equipment that you have to buy but rather buy into the system
and into the thought that this will be saving you money for many years to come. The first step
in the process is getting a piece of equipment that will let you be able to take accurate samples
out of the field you are want to spread fertilizer on. This can be done by buying a simple soil
probe for fifty bucks, or if you are going to be covering a lot of acres you can buy a probe that
you can mount on an ATV or a gator that will let you take more accurate samples and at a faster
rate. We use a “Simple Simon” soil tester that we mount on a John Deere Gator and that makes
it so we can cover about seventy five acres an hour and if you don’t want to worry about doing
the sampling yourself there are companies that
will come out and soil probe for you.
GPS Sampling Equipment
Before you go out to soil probe there
are some things you have to do first. Every
piece of ground in Ohio can be found through
using USDA/Farm Service Agency to break up a
certain plot of ground into soil types. There are
companies out there that are helpful with
getting all this information into a useful form for farmers. We use a company called Ag
Spectrum and they take our fields and break them into soil types or “polygons” and send them
to us on a disk we can save to our computer.
When you are out sampling all that information is useless unless you have a way to track
yourself in the field, we use a hand held Trimble Guno series GPS unit that is capable with our
computers. With your field maps, soil types and free software downloaded onto your GPS and
whichever soil sampling equipment you are going to use you can go out and soil sample.
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7. GPS/ Controller Equipment
After buying the first pieces of equipment the rest of the pieces you need are probably
already found on the farm. The auto guidance you use to
plant corn you can convert to control your variable rate
spreader. At our farm we use John Deere Star Fire GPS
guidance system and you can use this to spread with by
buying an upgrade to put on your in cab computer. After
you have this upgrade installed and your field maps
downloaded onto your cab computer, the computer will
adjust the amount of fertilizer you are spreading according
to your field map information.
Spreaders
With all of this in place the question now is what spreader to use. Any spreader that
uses a web in the bottom of the spreader to push the material can be used to variable rate
fertilizer. In most of your conventional spreaders the web is ground powered so the amount
you are spreading is depended upon how fast you are driving and how far open your rear gate
is open that lets the material feed out. On a variable rate spreader the web speed is
hydraulically powered from your tractor, by speeding up or slowing down the web to control
the amount of material applied. There are a lot of spreader
manufacturers and prices can vary a lot.
All of these steps can be confusing but there are today a lot of
companies that will do the hard work for you to make this a time and
cost efficient way of getting the right amount of fertilizer you need on
your farm.
Financial Cost and Benefits of Variable Rate Fertilization
In this section of the report we will be discussing the financial cost and benefits of
variable rate fertilization. We will start by discussing the financial cost of using variable rate
fertilization. The first thing you need to know before investing in variable rate fertilization is
that for it to be profitable a field needs to have a wide range of soil test levels (Murdock&
Howe,1997). If a field has only a small amount of test soil variability it will not justify the
expenses to use variable rate fertilization (Murdock& Howe, 1997). The first thing you need to
do before investing in VRF is take soil samples of the fields you plan to use variable rate
fertilization on (Murdock& Howe, 1997). Most soil samples test cost between one to five dollars
per acre (Martin, 2005). After you decide to invest in variable rate fertilization you have to buy
the technology and the equipment that is used. When using VRF you have to buy global
positioning equipment and computer software. Most GPS units cost around 2,300 dollars while
the software for these units cost around 2,200 dollars (Martin, 2005). Besides buying
equipment you also have to purchase maps of the fields you plan to use VRF on (Murdock&
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8. Howe, 1997). The average cost per acre for maps is around four dollars (Martin, 2005). After
you invest in all the equipment and technology you then have to buy fertilizer. The most
common form of fertilizer used in variable rate fertilization is potassium and phosphorus
(Murdock& Howe, 1997). Potassium usually cost around 650 dollars per ton while phosphorus
usually cost around 850 dollars per ton, but these prices are subject to change because of
changes in the market (Barker, 2008). In 1997 the University of Kentucky conducted a test using
variable rate fertilization and found that it cost around eight dollars per acre to use variable
rate fertilization while it cost around four dollars per acre using the normal method (Murdock&
Howe, 1997). But in 2008 The Ohio State University conducted a study using variable rate
fertilization and found that it was cheaper to use VRF rather than the normal method (Barker,
2008). This was the result of the rise in fertilizer prices. So within the past decade the cost of
investing in variable rate fertilization has become more justifiable because of the rise in
fertilizer prices.
As fertilizer prices have risen the financial benefits of variable rate fertilization have
become more noticeable. When starting out with variable rate fertilization it may seem
expensive but in the long run it can reduce risk and it will improve economic returns by
improving the efficiency of fertilizer use (Hall, 2011). The Ohio State University conducted a test
using variable rate fertilization on a forty-five acre central Ohio farm and determined that using
variable rate fertilization could save farmers thirty-three to eighty-eight dollars in fertilizer
prices versus not using variable rate fertilization (Barker, 2008). Variable rate fertilization can
also provide greater economic returns in years of drought (Hall, 2011). Some tests have even
shown an increase in crop yields using variable rate fertilization. One test involving cotton
showed a nineteen percent yield increase in just three years using variable rate fertilization and
precision agricultural tools (Martin, 2005). Variable rate fertilization is most profitable when it is
used on a field with large test soil differences (Murdock& Howe, 1997). The most important
factor in determining whether to use variable rate fertilization is the economic return of each
dollar that is invested (Hall, 2011).
Installation
There is not much installation of these products unless you are installing it on an older
piece of equipment then you will have to call a professional. If you buy a new spreader you can
get it all set up to do variable rate but there will be a big difference in the prices of the normal
spreader and the variable rate due to the hydraulic pump and all the technology you need.
Learning Curve
The learning curve on all this variable rate technology is pretty steep. For the younger
generation that grew up on technology it might be a little less steep but you will still need
training or at least a walk though on everything there is. There are a lot of parts and little things
that you will need to know about it, so it will help to have someone who knows about it to help
you learn it.
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9. Maintenance
There is not much maintenance on all this equipment. You just need to keep all your
variable rate pumps greased. With the technology if something goes wrong 9 times out of 10
you will need to call someone and get help. All the companies have a support line you can call
and get help 24 hours a day.
Pros/Cons
For every new piece of technology/equipment there are always pros and cons but I
think the pros out way the cons. Some of the pros to this equipment is the amount of money it
will save you in fertilizer costs and if you don’t have GPS in your tractor you will love it. The
biggest con there is, is the cost of the equipment. It is pretty expensive but it will pay itself off in
a couple of years. Some other cons is the learning curve and making sure you know how
everything works.
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10. Conclusion and Recommendations
Into today’s agricultural climate, land prices and fertilizer prices are on the rise, so our
group recommends that farmers should incorporate variable rate fertilizer technology to their
farm. Therefore, we also recommend these things to ensure that you are getting the most for
buying this new equipment.
Keep using and find the best resources. Getting only part of the system will not benefit you.
Buying quality equipment will benefit you when you go out to apply.
Do research to find the best company that will assist you in doing the lab work and
building your field maps.
Keep doing this system, you will see fertilizer cost go down immediately, but bushels an
acre may take a couple years to be noticeable.
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11. References
Murdock, L., & Howe, P. (1997). Profitability of Variable Rate Fertilization on a Kentucky Soil. Retrieved February
10, 2012, from, http://www.uky.edu/Ag/Agronomy/Extension/ssnv/ssvl1810.pdf
Hall, M. (2011). Does Variable Rate Fertilization Pay. Top Crop Manager. Retrieved February 10,
2012, from http://www.topcropmanager.com/content/view/769/38/
Barker, J. (2008) Today's Higher Fertilizer Prices Show Even Greater Savings for Precision
Agriculture. Retrieved February 10, 2012, from
http://ohioagmanager.osu.edu/uncategorized/todays-higher-fertilizer-prices-show-evengreater-savings-for-precision-agriculture/
Martin, S. (2005, October 18). Estimating Total Costs and Possible Returns from Precision
Farming Practices. Plant Management Network. Retrieved February 17, 2012 from
http://www.plantmanagementnetwork.org/pub/cm/research/2005/precision/
Variable Rate Spreaders. (2012). Retrieved from
http://www.newtoncrouch.com/pages/view/42
Simple Simon Soil Sampler. (2011). Retrieved from http://www.pargps.com/pr01.htm
Fasching, R. A., M.S.., & Agronomist, S. (n.d.). Soil Sampling for Variable Rate Fertilizer Application | Montana
NRCS. Montana NRCS. Retrieved February 26, 2012, from
http://www.mt.nrcs.usda.gov/technical/ecs/agronomy/technotes/agtechnoteMT89.html(tags: none | edit tags)
Reetz, H. (n.d.). Precision Agriculture Present And Future - PrecisionAg. PrecisionAg. Retrieved February 26, 2012, from
http://www.precisionag.com/viewpoints/haroldreetz/?storyid=1397 (tags: none | edit tags)
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