Monthly Archives: December 2010

What a difference a couple of days and 50 deg in temperature makes!

Changes Not Resolutions…..

Let me say first off that I hate New Years resolutions and all the attention that they get this time of year.  Why you ask?  Because if it takes a flip of a calendar for someone to get all excited about making a change, well then they are not all that eager to change in my opinion. 

But that’s just me………. 

So what am I going to do today, well talk about some New Years changes here at the Robertson Farms Blog………..but they are not resolutions.  

I started a blog two years ago to let off steam, to give all that pent up frustration and feelings a place to go and if anyone read it, then fine, and if they didn’t, then fine.  Looking back I went off the deep end a few times.  OK more than a few times.  Many times in fact, which means I must have needed to vent.  It was very therapeutic.  

Then a year ago I decided that I did care if anyone read it and I did care what I was saying and how it was taken so I upgraded to something a little more “professional” than the old Blogger account and stated this website.  And I tried very hard to post things for my family who are not in this area, so they could see what we were doing. I also tried to post things from an Ag perspective to advocate for all of Ag, especially for Southern Illinois AG, and to educate as well on things of interest to me.  Things like ham radio, agronomy, camping and shooting.  

The response was 4 X in the first two months from the old blog to the new page and now in a year it has gone 4 X again.  So thank you to all my readers and followers on this page, Twitter and Facebook.  As of today about 1400 of you are regular followers now in some fashion.  That is great and scary at the same time.  Great that you care and also that what I put up is interesting; but scary in the fact that what I post needs to move up a notch as well.  

The Changes…….. 

While I know I can’t guarantee what I am about to propose will go off without a hitch, I am going to give it a try.  So for 2011 here are the changes you should see on Robertson Farms……… 

  • Less venting, which means that I won’t be posting very much if anything about Civil Air Patrol or Politics.  You know as well as I do that when the meter pegs I will have to throw something up but I hope it is very, very infrequent.  To that end I have vowed to remove myself from most activities that put me in contact with CAP or politicians.  We will see how long it lasts. 
  • More education which means doing some teaching or illustrations along with the blogging. I want to start some video blogs and talk about things more than write about them……….again working on the details. 
  • More Ag……as in more about my farm, agronomics, and growing crops…..and Ag related topics which fit with #2. 
  • More pictures and illustrations to help with #2 
  • Less block type so its easier to read, per the request of several readers 
  • More on camping, fishing, hunting, guns and outdoors stuff.  Everyone seems to like that stuff a lot.   
  • Post on ham radio when there is something that is more unique than what is already out there or special projects.  The web is saturated with the same old stuff and I don’t want to add to the staleness. 
  • More pictures and video including more Youtube videos………… 


I hope this makes things better for the reader as well as those who drop by looking for advise on a topic.  I hope it also keeps things fresh………… 

I hope followers keep coming and we keep growing.  

And to celebrate, I am going to take the rest of the year off………and rest up for the new challenges of 2011.  

See you all Jan 02, 2011. 


Last night we had some fog and it froze to the trees…………

Plus the sun rise was reflected against the ice crystals in the sky left over from the fog and it gave off a pretty red, orange and pink cast that this picture doesn’t go justice to.

Started Hauling Jan Corn yesterday, had a few problems but did get a start on things………..

The Santa Claus I want to meet!

Well here it is on Christmas Eve and it is snowing.  A good ol’ heavy wet snow.  Not bad, and only 12 hrs earlier than the weather man said, but we will take it. 

From all of us here at Robertson Farms

 to all of our Friends, Family, Readers and Followers

May the Happiness and Good Cheer

of the Christmas Season be yours

throughout the New Year.

Merry Christmas!

Part 3 of grids vs zones. You can down load the U of I Grid Testing Pamphlet Here as a PDF 


There are two basic methods of making a fertility recommendation no matter how one samples the soil.  You are either using either the Build and Maintain approach or the Nutrient Sufficiency system for making fertilizer recommendations.  Both methods have their own strengths and weaknesses which are well known in the industry and the descriptions of both are well publicized on the web so I won’t take time to go into those here.   Each has its place in the Corn Belt and in different management systems and the farmers approach to their cropping systems.  The most important thing is to adapt one approach and stick with it during the initial phase of implementing your directed nutrient programs.  

Assuming that you have done your best with either grids or zones to capture the true variability of nutrient levels and holding capacity in the field you have tested the next two steps in the process often result in why farmers are dissatisfied with their soil testing programs and the results they obtain.  Both problems are a result of improper calibration or the methods used to make the recommendation.  Because we introduce more variability into the system, the result of follow up testing is not “where it should be” based on the amount of nutrients applied to the soil.  These two problems are crop removal/nutrient replacement and using yield maps to direct recommendations. 

What goes wrong? 

When using crop removal/nutrient replacement charts the result of subsequent soil test can show lower than expected nutrient levels in the soil.  This is pretty common place here in my part of the Midwest.  The reason I think is two fold and simple:  first the crop removal charts are wrong or too low for our newer hybrids and second our soils clay types and holding capacities tend to tie up “fresh” fertilizers.  Farmers and consultants need to do individual calibration of these removal charts for their soil types and cropping rotations to see what the actual removal or replacement rates are.  For instance in my area to maintain a soil test level of P or K, I need to add 1.25 to 1.5 times the nutrient removal rate for that nutrient depending upon CEC or clay types.   By doing so my soil test levels tend to be very predictable from one testing cycle to another however drought or excessive moisture can cause these levels to fluctuate and that is expected.  

The biggest complaint I get from farmers who have entered into a grid soil sampling program with other companies or consultants is the lower and in some cases incredibly lower soil test results in subsequent testing cycles because they have been sold and assume that by incorporating a yield monitor to calculate the actual removal rates their fertility maps will “even out”.    First your fertility maps most likely will never even out.  Second if your using crop removals then we already know that there is a high likely hood that your soil test values will be lower at the next testing cycle.  Third the improper calibration of the yield monitor adds another level of variability to the equation.  When you add one error to another you don’t get two errors, you get four!  

Why Yield Maps Fail 

Unfortunately most farmers calibrate their yield monitors wrong.  They calibrate for accuracy with truckloads or scale tickets.  Doing so causes individual yield points in the field to be off dramatically on the high and low ends of the yield range.  The map above shows a field with 6015 yield points.  Because of improper yield calibration 45% (the yellow points) are not in the range of the calibration the farmer did and are inaccurate.  So applying a crop removal rate that is low to a yield point that is also inaccurate causes the resulting soil test levels to be way off.  This is not a hard problem to fix or detect.  Follow the instructions in the manual for proper yield monitor calibration and have your crop advisor check you calibrations as you harvest.  You should also have your consultant check each yield map prior to using it in you fertility program to see if it is any good for making a recommendation off of.  

What to do?

With only 20% of farmers using a directed nutrient management program is it no wonder why so many have just gone back to blanket applications?  We need 80% or more of farmers using directed or site specific nutrient management programs before we are mandated to do so by the EPA. There are numerous consulting agronomists in the Corn Belt who know how to calibrate yield monitors correctly and do the kind of analysis shown above to insure that your data is good when it goes into your recommendations.  These same consultants also know how to calibrate removal rates to local conditions. If you cant find one let me know and I will put you in contact with one of the many I am familiar with, associated with or have worked with.   

Simply taking a soil test and then entering it into a computer program to make a recommendation with inaccurate data like removal rates and yield maps will result in a big fail when the program is reevaluated with subsequent testing.  Getting things right, from mapping the most variability in the field accurately with soil test and yield monitor, then applying correct removal and buildup rates to those variables will insure success.

Part II of Zone vs. Grid Soil Sampling.  Part 3 tomorrow

The Grid History.

Although touted as a new and very accurate method of soil sampling by various universities, agronomist and agronomic groups in the last twenty years, using a grid pattern for soil sampling is nothing new.  Grid soil sampling was advocated by the University of Illinois in a publication called Test Your Soil for Acidity in 1923.  New developments in technology have only slightly updated this 90 year old approach to soil sampling.  

The U of I pamphlet contained descriptions and guidelines on how to sample a field using a grid pattern by steps or pace count.  The pamphlet also showed farmers how to make color site specific application maps by using the grid points and colored pencils or crayons to color or shade zones based on the nutrient treatment recommendation for each grid point.  The application maps very closely resemble the “kriging” VRT maps of today.  In reality only two differences exist between 1923 and 2010:  One is that we now use computer processors to create color maps instead of graph paper and crayons.  The other is the sampling density or number of acres needed to comprise a grid cell has changed over the years.  

In the 1980’s grid soil testing began to take hold and grow in the corn belt due in large part to a soil testing business called Top Soil Testing Service.  Top Soil did grid soil sampling on many acres of corn and soybean production and were the leaders in establishing the use of GPS for creating field maps in the early 1990’s.  By the time the mid 1990’s arrived GPS guided grid soil sampling was becoming the norm as an explosion of field mapping software and VRT technology began to develop and grow.  The use of GPS and computerized mapping programs allowed for grid soil sampling to move from a labor intensive “guess” of grid design and sample location to a more precise and repeatable process that could be done by anyone with very little computer training.  

The Reason for Grids 

Grid soil sampling has as its foundation the systematic approach of evenly spaced sampling points within a field.  Evenly spaced points allow for even distribution and equal distance calculations or inverse distance analysis to be done on the data collected to estimate power or strength of one grid point result against the other neighboring results.  The output of these equations is an estimate of what the nutrient map could look like if it were analyzed on a foot by foot basis.  These numbers can then be kriged or interpolated to produce the same “feed sack” maps that were shown in the 1923 pamphlet.  

Modifications to the Standard Grid Sampling Program. 

Sampling a field on a 5, 3.3, 2.5 or one acre grid simply because that is the agronomicly accepted practice for an area or because that sampling scheme fits well with the consultants or labs mapping software is a poor excuse for sampling.  If the reason for soil sampling is to capture variability and treat that variability then using a rigid method of sampling that introduces more variability or does not allow for proper treatment of the variability does not promote profitability or a true site specific management program.  The results of any rigid program will be less than ideal and in many cases can lead to poor conclusions and improper or inadequate fertility treatments. 

The major weakness of grid soil samplings is the assumptions made starting at sample collection.  Except in rare instances in the soil sampling industry, no allowance is made for any in field variability with regard to soil type, texture or color, landscape position, past management or production practices or other soil site factors that could or do lend themselves to different nutrient holding capacities in a grid soil sampling program.  In addition the analysis of the equal distance sampling points can introduce variability that doesn’t exist due to afore mentioned soil site factors. 

Soil site factors that guide zone establishment in a Zone Sampling program should be used to modify the grid soil sampling map as well.  Using or establishing “smart grids” based on these factors can allow a consultant or agronomist to eliminate a lot of induced variability that a systematic grid program can lead to.  Smart Grids can be made to match, follow or mimic these soil site factors while still allowing for the same sample density in the field.  They can also still be equal distance while constrained by soil type, landscape position or past practices.  This allows for more accurate interpretation of the results and can be related directly back to the soil sample map or field and not to a generic color interpretation of what the field “might” look like.  

The major drawback of using smart grids is that it eliminates the “drive the field boundary and apply a grid” methodology of many field technicians who need to get over a large amount of acres in a day.   It also requires that each soil core be examined and could lead to grid modification based on observation at the time of sample collection thus eliminating any gain in sampling “efficiency” that the pre plotted points offer.  

In addition to modifying the grid layout to “smart grids” some attention needs to be paid to grid size or the number of sampling points in the field.  Large fields that are homogenous with regard to the soil site factors mentioned can have a larger grid size and a smaller number of collected samples due to the lack of in field variation.  Smaller fields, larger fields that are made up of several smaller fields from past management or production practices or irregular shaped fields need to have a much smaller grid pattern and more collected samples in order to capture the variability correctly.  Grid size and the number of sampling points should be adjusted on a field by field basis to insure you correctly capture the variability of the field.  

Smart Grids and Smart Grid Sampling is a grid sampling program that is done on a field by field basis, matching grid size and sampling density to all know or observed soil site factors in order to accurately map maximum variability to aid in a directed nutrient placement program (VRT).  

Grid Sample Depth and Frequency 

All core samples should be taken to the depth of the furrow slice (6-7 inches) or modified based upon tillage practices or the lack of tillage (no till) for the farm. Grid samples should be collected on a regular sampling interval based upon crop rotation, fertilizer or manure applications, or tillage practices.  In some instances under high management it would be appropriate to sample fields every year.  Fields with high test levels or fields receiving manure should be tested every year.  In other cases sampling every two years under a corn-soybean rotation or under a bi-annual fertilizer application would be appropriate.  No more than three years should elapse between sampling intervals

There has been some email discussions going on as to why one would grid sample a field vs. zone sample the field.  I thought I would dust off part of a paper I did for a presentation to the state NRCS at one time on why I sample the way I do.  So for this blog post, here is why I and how I zone sample.  Grids are next.

Zone Samling and Soil Sample Location

Each sample should represent a uniform soil area with similar past management. It is recommended that each sample represent 10 acres or less. Sampling areas should be determined by the soil type, soil color, topography, drainage, past management of the field, manure applications or presence of livestock and productivity.  Maps of soil electrical conductivity (EC) and GPS yield maps can aid in distinguishing between field areas with contrasting soil properties or crop nutrient removal.  

Consultants should use field observations at the time of sampling to determine which local site factors should guide their sampling pattern within each field.  Soil survey maps, GPS yield maps, bare soil images and input from the farmer as to past land use (fence rows, pastures, building sites and old field divisions) can be used to create geo referenced zone maps of these factors prior to soil sampling to help guide the consultants sample locations in combination with his or her field observations.  

Soil sample zones should be recorded via GPS or geo referenced maps to insure location and repeatability of sampling.  This also aids in refining the sample zones as more information becomes available about the field or soil and allows the zone to be used as part of a directed nutrient application (VRT) program. 

test soil

Sampling Depth, Collection and Frequency

Soil sample probes should be taken to the depth of the furrow slice (6-7 inches) or modified based upon tillage practices or the lack of tillage (no till) for the farm.  Each sample should consist of between 10 and 15 cores with cores being collected in a zig zag method thought-out the sample zone.   Each core should be examined prior to placement into the sample bag to insure that it conforms to color, texture and depth for other samples in the management zone.  

Each soil sample should be air dried and all cores in the sample should be ground and thoroughly mixed prior to submission to the laboratory for analysis.  Doing so insures that each sample is truly a representation of the sample area.  

Soil samples should be collected on a regular sampling interval based upon crop rotation, fertilizer or manure applications, or tillage practices.  In some instances under high management it would be appropriate to sample fields every year.  Fields with high test levels or fields receiving manure should be tested every year.  In other cases sampling every two years under a corn-soybean rotation or under a bi-annual fertilizer application would be appropriate.  No more than three years should elapse between sampling intervals.

Thought this was pretty good camera work plus check out the recoil absorption in the body.

Over the last 20 years I have had held some different professional certifications and memberships.  Those include certifications as a Certified Crop Advisor (CCA), Certified Professional Agronomist (CPAg) and a NRCS Technical Service Provider (TSP) among others.  Holding these certifications and memberships costs a lot of money.  Not in the actual fee of membership, but in the different requirements for keeping the certifications current.  

In the not-so-distant past I let my TSP go.  The amount of time and hoops to jump through for a certification and re- certifications became ridiculous for something that is pretty much useless to me and those whom I consult with.  It became evident to me that the NRCS really did not want non-government professionals doing their job.  Plus, they don’t pay near enough on those jobs to justify doing them.  I know others think differently, but as with all things governmental, life is too short for that much red tape. 

The CCA is basically a way of stating that a fertilizer dealer knows what they are doing.  I am not a fertilizer dealer, nor do I ever plan on being one at this time. But making fertility recommendations is something I do, so I thought it wise to get that certification.  I have never used it for anything, nor have I had to.  Being certified now for 15 years, I am wondering why I go and pay for meetings to keep it current when the topics of the meetings are not current.  These meetings are not cheap when you figure in business time lost, meal and travel expenses, plus the actual cost of the meeting.  In some cases it figures out to be over $100/hr credit.  

The CPAg is something I am very proud of.  I think it is a true certification for an agronomist.  A certification that allows one to be an agronomist and also specialize in a particular discipline without having to get credits in areas that you don’t deal with.  The CPAg is more than just a test and code of ethics like the CCA.  The certification looks at the entire person, their work experience, academic history and study as well as professional references that one knows what they are doing.  You must take the CCA exam as well, but that is a minor part of the CPAg certification. 

This past year it has been difficult to get CCA credits in this part of Illinois.  I have spent a lot of time on line taking tests for credits.  In Illinois all the CCA meetings with approved credits take place up north, it would seem, and none are very well advertized, so that one can make arrangements to get to one.  You either know where a meeting is or you don’t.  I have visited the Illinois CCA website numerous times but they don’t seem to keep it current and most of the meetings listed were held in 2008 and 2009.  And I don’t seem to be on any mailing list to get newsletters for some reason.  I don’t even get the “official” CCA magazine anymore even after repeated attempts to register for it online.  

So maybe I am out of the loop……………..if I am, then that explains my lack of enthusiasm for the CCA anymore.  And if I am in the loop and this lack of communication to the CCA’s from the state is normal then maybe that explains my lack of enthusiasm for the CCA anymore.

Here is an out the back door picture showing the snow………

Been off line for the last four days, my hard drive went out.  I have been reduced to my phone and a notebook computer that I cant seem to get to do much, don’t know whats wrong with it.  But I hope Tyler gets me going again in the next day or so………..

Don’t forget you can hear the entire presentation at the 2011 Farm Futures Management Summit Jan 4th and 5th in St Louis.  Register Here.

This is just to funny……..

Current Farm Weather


Did a theme update but some features may not be working correctly, please report any issues I have not found. Thanks!