# On The Value of Soil Testing for Forage Production



## vhaby (Dec 30, 2009)

I've been invited to talk or a local farm and ranch club about soil testing. So far, my plan is to briefly discuss:

-Plant nutrition

-Soil as a storehouse for plant nutrients and water

-Soil acidity and plant nutrient availability

-Liming and limestone quality (with some research results)

-Fertilizers (with some research results)

-Soil sampling

-Interpreting soil test results

Hopefully this presentation won't be "preaching to the choir." In that regard and knowing that most of you are well-educated on this topic by your education and readings on "HayTalk," what would you want to know more about relative to this topic? The talk is on February 15th.

Vincent


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## VA Haymaker (Jul 1, 2014)

One of the things that was NOT impressed on me when I did my first soil analysis was expected yield as part of it and it's different applications for haying vs pasturing. One thing to lime and fertilize for grazing, another for baling and selling hay, i.e. max yield.

Also - IMHO, the owner should note the accuracy of application with whomever spreads, if hired done. Frequently, again IMHO, the guys putting down lime and fertilizer are there to dump and run. It may be of benefit for the owner to spread themselves with their own equipment or a rental.

A stark observation... When we reclaimed our old fields, they were in such bad shape - mined out from others haying it. As we brought up the PH levels, the response to fertilize was amazing. Don't underestimate or skimp on lime.

Break a leg...;-)

Bill


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## glasswrongsize (Sep 15, 2015)

Vincent, If I were attending with my current knowledge level, I would tune in especially hard to the parts concerning how PH "ties up" nutrients ...not so much THAT it does, but HOW it does? (might be covered in your "Soil acidity and plant nutrient availability" portion?)

I would also perk up more to anything you have to say on CEC (how to effect it, how much CAN I effect it due to my soil type, ... basically ANYTHING in-general as I lack suitable working-knowledge) Maybe already to be covered in your "Interpreting soil test results" portion?

Since there are so many different soil types and healths (mine is also POOOOOOR and had been mined of goodies), I would listen closely to WHEN to start "worrying about" the (micro or macro or whatever) other things such as boron, sulfur, etc. Example, some of my last-year's new ground has soil tests indicating 4.8ph, P of 14is and K of 80ish. Probably not much sense in worrying about my sulfur levels until I get everything else in order.

See, my suggestions prolly seem moronic....but that just shows-ta-go-ya how dumb I am, and that others in your audience may be nearly as ignorant as I.

Mark


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## somedevildawg (Jun 20, 2011)

I would speak on OM and trying to raise it and the benefits associated with it......good luck with the speech, I'm sure it will be informative


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## IH 1586 (Oct 16, 2014)

I agree with the last two on PH and OM and benefits of it. Until I really started to research and look at different aspects of soil health, I never realized important PH was. Sure we soil sampled and the only time lime would be utilized would be taking corn stubble and putting back into sod. The rest of time samples were utilized for fertilizer. Who knew lime could be more important.


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## swmnhay (Jun 13, 2008)

Maybe you were already but discuss the Micros.Sulfer,Zinc,Boron,etc


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## hillside hay (Feb 4, 2013)

I don't know if you are covering it already but perhaps address the importance of soil testing before buying land. Some ground is just too far gone for what a lot of sellers asking price is. Rental as well I suppose


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## Tim/South (Dec 12, 2011)

Two things already stated. Organic Matter and binding.

I still do not understand the binding part as much as I would like. My brain just interprets that things are out of balance and to get that corrected.


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## Troy Farmer (Jul 31, 2011)

Just mtw, you might want to emphasize the difference in management for pasture vs. hay. Around here it is not stressed enough. Haying is hard on the soil where as pastures are more like a replenishing system. It took me a long time to understand that.


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## reede (May 17, 2010)

Good thoughts here from everyone.

Depth of soil test, and applicability to which nutrients move and may be available at different depths. Also the effect of depth on how test results are expressed, such as ppm or lb/acre.

Importance of having OM on the test. Here, with Clemson's lab, OM is a separate, additional cost test not included in the standard package. I always get it, and for a while had to convince the local county agents that I actually did want to pay more for my soil test.

OM and its importance on holding moisture in the soil. Since y'all get dry out there from time to time, of particular importance.

Which nutrients are more stable or more mobile in the soil. Knowing which ones, even if levels are good now, you need to plan to add to keep them there, and which ones may hang around for a bit.

Maybe examples of just what some of the ratios that we are dealing with are like.

Putting out a ton or 2 of lime to the acre sounds like a lot of stuff. But, assuming 2million lbs/acre soil, 1 ton is 1 lb lime to 1000lbs soil.

Increasing soil OM by 1% will gain you 1/2 an inch of rainfall held in the soil. But 1% is 20,000lbs OM, kind of a daunting number. But plants and their roots are amazing things that can build it quicker than we would think possible.

Reed


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## hog987 (Apr 5, 2011)

Read an article once about soil. How well soil performs was broken down like this. 70% soil structure, sand, silt clay, compacted or not. Structure is usually hardest to change and we farners work with what we have. 25% is soil biology. This is just starting to get focus in recent years. 5% soil chemistry. This gets most if the focus as proof by the replies here. Good producing soil has a lot more to do with just lime and fertilizer and I think more focus needs to be made on structure and biology.


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## RockyHill (Apr 24, 2013)

Hope you will have your talk recorded and post it here on Hay Talk. I'm sure we all would learn something new, be a refresher on other things, and a good resource for newbies coming here for sound information.

Shelia


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## qcfarms (Dec 14, 2014)

Might want to talk about the different soil testing that is available as well. I know in the soil health arena the Haney Test and the Solvita (sp?) test is getting quite popular. They do seem different than the normal soil tests that you typically get for pH and fertilization. Your outline looks excellent!


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## SCtrailrider (May 1, 2016)

Yes you should record it, I would like to be able to hear it or watch a video..


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## dirtball08 (Jun 26, 2011)

Yup I third that motion. Record or video please.


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## vhaby (Dec 30, 2009)

Excellent ideas- all. My responses follow:

"Also - IMHO, the owner should note the accuracy of application with whomever spreads, if hired done. Frequently, again IMHO, the guys putting down lime and fertilizer are there to dump and run. It may be of benefit for the owner to spread themselves with their own equipment or a rental." Bill- Central Western VA.

Bill, thanks for this reminder. Until finally owning our own place, I hadn't given spreading speed much consideration until I saw the effects of speed on turns in my alfalfa and how the truck tires were tearing up the stand. I promptly fired that company from ever spreading fertilizer on my alfalfa again, and eventually found a privately owned fertilizer company where the owner/driver was very careful in turnarounds and actually drives at a very slow speed when spreading straightaway even on our grass forage. VH.

"...some of my last-year's new ground has soil tests indicating 4.8 pH, P of 14s and K of 80ish. Probably not much sense in worrying about my sulfur levels until I get everything else in order." Mark- IL.

Mark, your soils test like many of ours in East Texas. In the past, I have found soils that have a pH of 4.5 and even lower, phosphorus in the 3 ppm level, and potassium of 40 ppm or less. Many of our soil CEC levels are three or less. Actually, you would do well to worry about all plant nutrient levels including sulfur, especially nitrogen, phosphorus, potassium, calcium and magnesium (from limestone), and sulfur as the main considerations. In our soils, micronutrients appear to be less of a problem on forages except for boron on legumes on limed soils. Other than liming to raise soil pH and addition of organic matter, there is not a whole lot that can be done to increase the cation exchange capacity of these soils. VH.

"address the importance of soil testing before buying land. Some ground is just too far gone for what a lot of sellers asking price is. Rental as well I suppose " Hillside- Broome cty NY.

This is very important, but unfortunately, is usually not recognized by the seller, as they will take the highest offer regardless of the soil condition. When purchasing our small ranch the seller rejected our first offer. We then requested permission to sample the soils before agreeing to a second offer. To our surprise, all of the surface 6-inch depth samples tested above pH 6 and the 1-foot depths to 48-inches deep tested above pH 5.5- exactly what we were looking for to grow alfalfa. We did not however, tell the sellers what we found but did increase our offer, which they accepted. VH.

"Haying is hard on the soil whereas pastures are more like a replenishing system." Troy- upstate SC.

This is an excellent point. Haying requires greater amounts of nitrogen to be applied with the subsequent more rapid increase in soil acidity and the increasing need for more frequent limestone application to maintain the correct soil pH. Long-term grazing makes pastures quite fertile even in depths to 18 inches or more. Plant nutrients recycled by livestock grazing and defecation, with the help of micro-organisms breaking down the organic material, and dung beetles moving manure balls deep into the soil, and long-term leaching greatly improves plant nutrient availability. This is especially important as the surface soils begin to dry out and plant roots can no longer take up nutrients from the more fertile topsoil. VH.

"Putting out a ton or 2 of lime to the acre sounds like a lot of stuff. But, assuming 2 million lbs/acre soil, 1 ton is 1 lb lime to 1000 lbs soil." Reed- Laurens SC.

The acidity in soil is a very weak acid that is easily neutralized by limestone application. Good point- "1 ton is 1 lb of limestone to 1000 lbs soil." I plan to take this one step further by saying that 1 pound of soil sample representing 15 acres and sent to the laboratory for analysis, represents 0.000003% of the acreage to be analyzed (if my calculations are correct). Therefore it is so important to take a sufficient number of subsamples from the 15 acres and mix thoroughly before taking the sample from the bucket to send to the laboratory for analysis. While serving as a technician in a soil testing laboratory, a farmer brought in a gravel shovel of soil in a 5 gallon bucket and wanted us to analyze it for fertilizer and lime recommendations. We declined to accept the sample, explained to him the importance of taking a representative sample, and asked him to resample the field and resubmit the new sample for analysis. VH.

"Hope you will have your talk recorded and post it here on Hay Talk. I'm sure we all would learn something new, be a refresher on other things, and a good resource for newbies coming here for sound information." Shelia- South Central KY.

"Yes you should record it, I would like to be able to hear it or watch a video.." SCtrailrider- Upstate South Carolina.

"Yup I third that motion. Record or video please." Dirtball08- Alberta, Canada.

Excellent suggestions, all three! I will investigate the possibility of doing as you suggest, but am not sure that Hay Talk has the capacity to present such a video. There might be a possibility of recording this as a podcast that can be linked on some other website. VH.

Thanks again for all your suggestions, and the more to come...

Vincent


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## Vol (Jul 5, 2009)

vhaby said:


> There might be a possibility of recording this as a podcast that can be linked on some other website. VH.
> 
> Thanks again for all your suggestions, and the more to come...
> 
> Vincent


You could place the video on youtube Vincent, and then you could link it here in a post on haytalk.

Regards, Mike


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## SCtrailrider (May 1, 2016)

Yes, a simple video then upload it to the tube....


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## endrow (Dec 15, 2011)

qcfarms said:


> Might want to talk about the different soil testing that is available as well. I know in the soil health arena the Haney Test and the Solvita (sp?) test is getting quite popular. They do seem different than the normal soil tests that you typically get for pH and fertilization. Your outline looks excellent!


 I know soil health is important we've been working for years to build up our soil health. I still use conventional testing CEC and organic matter are the only things my tests look at beside pH and nutrients. What is the advantage of the Haney and SP


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## glasswrongsize (Sep 15, 2015)

First, I looked up my tests and my numbers were misrepresented in my earlier post of my worst field...a little.

Maybe you could proffer suggestions for ranking-of-importance for various things for building soil health as BUDGET allows?

The following is an example of my thought process while weighing my checkbook. There is a high probability that I am doing it wrong...

1) The first money goes to taking and having-processed soil samples
2) apply lime.
3)The next thing, upon which I spend money is replacing the P and K removed by last year's crop.
4) The next thing, upon which I spend money is building soil health to my goals (6.5< PH, 75ish P, and 250ish K)
5) The next thing I intend (not there yet) is to pay for better samples to include results of other nutrients (so far, I only get PH, P, K, and OM levels in my test. I have, in the past paid for the CEC sulfur etc... results)

I will also lay-bare my ignorance for all to see and tell you how I arrive at my fertilizer application rate (per acre).

Sometimes, it is easier to know what people are doing wrong if you "see" them DOING it.

For consideration, I have @17 fields totaling @100 acres with soil-test-results ranging from 6.5ph, 90P, and 344K (best) to 4.9PH, 15P, and 140K. If none in your audience is expected to be such a small-timer, you may be wasting your time to read the long-winded explanation below.

I take my last year's yield (in TPA) and factor for the average of 12P and 50K per ton of dry matter removed (I actually don't factor for moisture levels thereby making my maint fert a little higher than removed)

I multiply each field's deficit (based upon soil samples) X number of acres to arrive at a total deficit over the totality of acres.

I then calculate the percentage-of-total-acres that each field represents

Next, I determine how much fertilizer I am willing to afford.For example, I may intend to afford 16 tons of fertilizer (I have a 4-ton buggy,so I also round to nearest 4 tons to make best use of my trips to the fert plant)

Knowing how many tons of fertilizer I intend to spread, I determine my "mix". I determine my mix by calculating tons of hay removed to arrive at the total nutrients removed for the TOTAL acres. I factor to "replace" at a rate of 25# 18-46-0 and 85# 0-0-60 per ton of hay. If, for example, last year, I removed 200 tons of hay, I would replace 5000 lbs of DAP and 17000 lbs of potash which is 11 tons; that would leave 5 tons remaining in my intended application (16 tons).

Next, I take my total deficit and calculate THAT fertilizer mix to arrive at another ratio of Dap and Potash.

Now, I take the hay-removal fertilizer mix (11 tons) and add the soil-repairing fetilizer mix (5 tons) to arrive at a final ratio for the total 16 tons. I order THAT mix

To determine application-rate-per-acre, I go back through and determine that each field will get enough pounds-per-acre (based upon yield) of the fert mix (the 11 tons) plus its proportional portion (based upon soil sample) of the other 5 tons based on the deficit.

The above is the way I do it because I don't know any better; my thinking is I replace removal fert and build-up fert at the same time and in the same pass as efficiently as I can . 1 buggy load may cover 3 or 4 fields and I only have to adjust pounds-per-acre between fields.

If I do a split application, I do the calculations each time to come out to buggy-load-wanted to checkbook-allowing ratio.

I know that was long winded, I wanted illustrate that some remedial suggestions may be in order (in case your audience is anticipated to be speckled with some that are in my dim-witted knuckle-dragging category)...especially when theoretical fertilizer is offset by laziness, financial consideration, variable rate fertilizer application not available, etc...

Mark

You are more than welcome to use me as the way-not-to-do-things if you see fit...I just don't know any better. I am not TOTALLY worthless; I can always used as a bad example.


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## qcfarms (Dec 14, 2014)

endrow said:


> I know soil health is important we've been working for years to build up our soil health. I still use conventional testing CEC and organic matter are the only things my tests look at beside pH and nutrients. What is the advantage of the Haney and SP


Endrow,

I'm no expert on the Haney but I am attaching a link that may help. I know it is more expensive but it seems to give a more accurate representation of what is actually going on below the ground.

http://dtnpf-digital.com/publication/?i=445173&article_id=2909138&view=articleBrowser&ver=html5#{"issue_id":445173,"view":"articleBrowser","article_id":"2909138"}


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## vhaby (Dec 30, 2009)

Mark,

A quick observation from your testament above...you are using 9 lb of phosphorus (P) removed per ton of dry matter (hay). Plant analysis determines the amount of P in tested forage. However, when you use 18-46-0 (DAP) at 25 lb per acre to replace that 9 lb of P, you are actually applying P2O5 . So, you are shorting the amount of replacement P. The percentage P in P2O5 is 43.64%. If you want to replace 9 lb of P per ton of hay using 18-46-0, you should be applying 57 lb of DAP. Also remember that much of the applied phosphorus gets tied up in the soil and is not readily available for plant uptake, but becomes plant-available over a number of seasons. A better idea is to apply the lime needed to maintain soil pH and apply the amount of phosphorus according to soil test recommendations.

As a soil increases in acidity, aluminum ties up plant available phosphorus. Liming the soil to raise pH prevents this tie-up. I'm forgetting the actual numbers from some of my previous research, but a strongly acid soil required about 30 lb of fertilizer phosphate to raise the soil test one ppm P, whereas in a well-limed soil, about 12 to 15 lb of fertilizer phosphate raised the soil test P level one ppm.

Vincent


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## vhaby (Dec 30, 2009)

hog987 said:


> Read an article once about soil. How well soil performs was broken down like this. 70% soil structure, sand, silt clay, compacted or not. Structure is usually hardest to change and we farners work with what we have. 25% is soil biology. This is just starting to get focus in recent years. 5% soil chemistry. This gets most if the focus as proof by the replies here. Good producing soil has a lot more to do with just lime and fertilizer and I think more focus needs to be made on structure and biology.


What you refer to as "70 % soil structure, sand, silt, clay..." is called soil texture, or the varying amounts of sand, silt, and clay in various soils. These are determined in laboratory hydrometer sedimentation tests. Soil structure really refers to whether a soil has granular, prismatic, platy, etc. configuration, usually in the B-horizon. Structure has a lot to do with how rapidly or slowly water filtrates through the soil. A single grained granular structure will have rapid water infiltration. A soil that has prismatic or blocky structure will have moderate water infiltration. And a massive or platy structure will have slow water infiltration.

My idea of an ideal silt loam soil, (20% sand, 10% clay, and 70% silt) will consist of about 45% mineral, 5% organic matter, and from 20 to 30% air and 20 to 30% water- the water and air being somewhat interchangeable.


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## vhaby (Dec 30, 2009)

Talk on plant nutrition, soil fertility, liming, and soil testing was given last evening and professionally recorded. Haven't reviewed the presentation that exceeded 30 minutes. Now must determine how and where to put it on a web site to link for others to review.


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## Vol (Jul 5, 2009)

vhaby said:


> Talk on plant nutrition, soil fertility, liming, and soil testing was given last evening and professionally recorded. Haven't reviewed the presentation that exceeded 30 minutes. Now must determine how and where to put it on a web site to link for others to review.







Regards Mike


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## vhaby (Dec 30, 2009)

Here is the link to the presentation that I gave on soil testing and related information on soil fertility and plant nutrition for forage production. You may already know much of this information but I hope this review will contain some information that you can benefit from while listening and watching this YouTube video.

https://youtu.be/z1PxDiTexhk

The Texas AgriLife Extension service ag communications specialist, Adam Russell, recorded the presentation and the Texas AgriLife Research computer technologist, Kelli Norman, worked with Mr. Russell to download the video and post it on YouTube. Both people are located at the Texas A&M AgriLife Research and Extension Center at Overton.

Thanks for your encouragement to record and post this presentation.

Vincent


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## r82230 (Mar 1, 2016)

Vincent,

Thanks, your first part about re-reading (or seeing/finding) is spot on for me. I've watched twice already, paused and re-played even. I[m surely going to have to re-watch (my brain must be something like urea, some info disappears BEFORE soaking in). :huh:

Thanks again, for taking the time and sharing your wisdom.

Larry


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## IH 1586 (Oct 16, 2014)

vhaby said:


> Here is the link to the presentation that I gave on soil testing and related information on soil fertility and plant nutrition for forage production. You may already know much of this information but I hope this review will contain some information that you can benefit from while listening and watching this YouTube video.
> 
> https://youtu.be/z1PxDiTexhk
> 
> ...


Excellent video. Good refresher for me. My son (11 at the time) and I went to our local one put on by Pennstate. First time for me to attend anything on soil and learned a lot. Aidyn enjoyed it as well, good father son time and he was just as into it as well that he was pissed when he got passed by when they handed out papers, the guy must have realized it and came back to him.

I do have a question if you don't mind:

I have a few fields that have multiple soil types and soil samples are based on the majority but sampling is done across the entire field. The acreage is not enough or the different types is in an area that would not be practical to separate. How much of a difference does it make when sampling if you cross soil types? With access to better mapping I am thinking of taking samples within the majority however I am wondering if I am getting to technical.

Attached is an example of one of the fields.


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## vhaby (Dec 30, 2009)

IH 1586,

As you may have noticed in the video of the 12+ acre fescue field, soils vary a lot. They vary tremendously even within a single soil type (series). In your case, you actually have only two soil series. Each series differs in the percentage slope. If I were to sample this field for soil testing, and since each series is a silt loam, for just one time I likely would sample the Alvira as one, disregarding the percentage slope. I would sample the Hanover 3-8 percent and 8-15 percent slope as one, and sample the Hanover 15-25 as one field. Have these three samples analyzed and if the analyses are anywhere close to similar, I would sample them as one field in the future.

If you do not have access to computer based variable rate fertilizer application equipment, it doesn't make sense to sample a field based on soil series.

If you will Google USDA NRCS soil names you can enter a soil name and bring up the soil description. In your case, enter Alvira, print the description and then go back and enter Hanover and print its soil description. Then compare the two described soils.


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## Tim/South (Dec 12, 2011)

Thank you for going to the trouble to get your presentation recorded and loaded. There is a world of information on there that I have a better understanding.


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## RockyHill (Apr 24, 2013)

Could the video be 'pinned' or whatever that would be simple to reference? Not only could newbies be easily directed but some of us wouldn't have to search for that "where is that good video on soil testing".

Shelia


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## r82230 (Mar 1, 2016)

Vincent,

I think I'm getting a little better understanding of why I need to lime more now than I use to have to lime (I'm fertilizing more). If you would look at the following and tell me if I'm on the right (wrong) track. I took some of these numbers from your presentation (about the 8.30 minute mark I believe) and am trying to correlate them to my situation.

If my goal is to replace 50# of actual Phos per acre, I would need to spread 108.6957# of 18-46-0 (DAP?) or 92.59259# of 11-54-0 (MAP?) per acre. AND I would need to spread 70.43478# of lime if applying DAP or 55.00# of lime if using MAP. In both cases figuring lime ECCE at 100% naturally. The 70.43478# and 55# are based off, the multiplication of 3.6 x 18 x 108.6957 and 5.4 x 11 x 92.59259 (units of nitrogen in DAP and MAP).

All of above being in theory only, but it appears I would need to spread more lime (or quicker intervals) using DAP verses MAP. And this cost should be included the possible pricing difference between MAP and DAP is my thinking.

Go ahead and slap me. Seems the more I know today, the more I DIDN'T know yesterday or today. :huh: :huh: :huh:

Good gracious I love your video. It's nice to have a bunch of pieces in the same place.

Larry


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## vhaby (Dec 30, 2009)

Larry, you are thinking correctly but, if I didn't say this in the video, the amount of lime to apply per pound of N applied as MAP of DAP, or the straight N fertilizer materials applied, is considered a "Rule of Thumb." Also the lime to apply to correct the acidity formed per pound of N applied is an average, so it could be more or less than the numbers I presented on that slide- the heading on that column that showed it to be an average was cut off in that slide. It's usually best to apply lime according to recommendations from a soil test.

Vincent


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## swmnhay (Jun 13, 2008)

vhaby said:


> Larry, you are thinking correctly but, if I didn't say this in the video, the amount of lime to apply per pound of MAP of DAP, or the straight N fertilizer materials applied, is considered a "Rule of Thumb." Also the lime to apply to correct the acidity formed per pound of N applied is an average, so it could be more or less than the numbers I presented on that slide- the heading on that column that showed it to be an average was cut off in that slide. It's usually best to apply lime according to recommendations from a soil test.
> 
> Vincent


Vincent,you explained that well,how a lot of things are guides and not set in stone.Unlike a lot of others that explain things as this is what the book says so that's the way it is.


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## r82230 (Mar 1, 2016)

Vincent,

Thanks, I do soil test, just now I'm going to consider the rule of thumb on lime needed with MAP vs DAP, that I didn't before.

The other note that I picked up in your presentation is regarding ECCE, where I was told the large sizes just lasted longer.

Boy, is it hard to make good decisions with BAD information.

Larry

PS just last year, my soil test called for 750# lime per acre, the fertilizer dealer told me I was wasting my money putting on 900-1000# lime per acre, that I should be spending it on more fertilizer. And the test was done before I spread MAP on my fields. Using your 'rule of thumb', and with this year's spread of MAP, I should be awful close. Naturally, the soil test will rule the day. The reason for 900-1000# was semi-truck hauled 50 tons of lime at a time.


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## vhaby (Dec 30, 2009)

Larry, when you were told the large sizes (of limestone) just lasted longer, the teller was correct. The large limestone particles do last longer- for years and years- but these larger particles have very little effect on soil pH.

The reason that the finer, higher ECCE limestone maintains a higher soil pH than the lower ECCE limestone is that the higher ECCE limestone is more reactive with soil acidity, raising pH to a higher level. Soil pH is a logarithmic function (number). So a pH of 7 is ten times less acidic than pH 6, and 100 times less acidic than pH 5. So if the higher ECCE limestone elevates soil pH from 5.5 to 6.5 and the coarser limestone only raises pH from 5.5 to 6.0, the higher pH is going to take a longer time to return to 5.5.


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## r82230 (Mar 1, 2016)

vhaby said:


> The reason that the finer, higher ECCE limestone maintains a higher soil pH than the lower ECCE limestone is that the higher ECCE limestone is more reactive with soil acidity, raising pH to a higher level. Soil pH is a logarithmic function (number). So a pH of 7 is ten times less acidic than pH 6, and 100 times less acidic than pH 5. So if the higher ECCE limestone elevates soil pH from 5.5 to 6.5 and the coarser limestone only raises pH from 5.5 to 6.0, the higher pH is going to take a longer time to return to 5.5.


Now that makes a lot more sense, thanks Vincent,

Larry


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