Just got soil test back ,need help!
 

I just got my soil test back,can someone put this in English?
Target ph:6.5
pH(1:2 Sample:Water) 5.1
A-E Buffer Value 7.60
It says to add a ton of lime per acre,I thought lime lowered the pH?
But is the ph 5.1?

Hunting is not a sport,it's a lifestyle.

RE: Just got soil test back ,need help!
 

The target PH is a end goal. 6.5 is about perfect for clover, and a good starting point for alphalfa(sp).

They mixed 1 part of your soil sample with 2 parts distilled water and measured the PH at 5.1

The A-E Buffer Value 7.6 is really good (I think), you ONLY need to add 1 ton of lime per acre to raise the PH from 5.1 to 6.5. That is VERY GOOD NEWS. I've heard of some guys needing 6-8 tons in some northern areas.

The purpose of Lime, AG lime, calcium carbonate, is to raise the soil PH to improve the uptake of nutrients for legumes (clovers, alphalfa, soybeans, ect) that deer really like. The following link can explain it in alot better detail than I can...

http://www.agry.purdue.edu/ext/forag...ions/ay267.htm

RE: Just got soil test back ,need help!
 

Fldeerman, the acid/base thing is kind of confusing.
pH is stated as a number 1 through 14...7 being neutral...with 1 being the most acidic and 14 being the most basic. When the number is less than 7, lime is added to lower(neutralize) the acidity which actually raises the number closer to 7 or your optimal 6.5. With your pH being 5.1, you need to "lower" the acid level by adding lime which will raise your pH number. Get it?
I don't really know why the saying lower the pH by adding lime came from since the acid end of the pH scale is the lower end.
Did this help?

RE: Just got soil test back ,need help!
 

Your soil sample is good news, like the others indicated. Your soil must be sandy, or at least loamy to only require 1 ton/acre of lime to bring the Ph in line. If the soil is sandy, you need to be concerned about leaching of minerals in the soil, and drought, since water tends to run through it quickly. A low area would be better if this is the case.

Just for comparison sake.... my Ph was 5.1 - and the requirement was 6-8 tons/acre to get the Ph above 6.5. With loose soil, you may find that you have to lime more often, than with claylike soil, to keep the Ph where it needs to be.


Good luck

RE: Just got soil test back ,need help!
 

My soil is a clay mix and yes I was suprised it was only 5.1.

Hunting is not a sport,it's a lifestyle.

RE: Just got soil test back ,need help!
 

FlDeerman; I was just wondering what you have growing on your soil now? Are there any legumes? Something doesn't add up with a lime recommendation of only 1 ton/acre. The pH scale is logorithmic (each point of pH is 10 x more acidic than the one above) and 5.1 seems too far down the scale for that amount of application. A buffer pH which is basic (>7) while the soil pH is acidic (<7) doesn't make sense to me.

Dan O.

RE: Just got soil test back ,need help!
 

The acidity measured in a soil and water mixture is designated as active acidity and is a measure of the pH environment of the root. This does not represent the total amount of acid in a soil. Soils have a large reserve supply of acidity held by clay and organic matter particles or in aluminum and iron compounds. As calcium and magnesium carbonates from aglime neutralize the active acidity in the soil solution, more acidity is released into solution from the reserve supply and the pH does not rise. This resistance to a pH change is called buffering. Buffering capacity of a soil is a function of the clay and organic matter content as well as the amount of aluminum and iron compounds. Soils that are highly buffered require more lime to raise the pH because they have a larger supply of reserve acidity that must be neutralized. Florida soils are aparantly "lightly buffered", allowing the PH to be easily neutralized with small amounts of lime.

In most laboratories, the buffering capacity (total acidity) is determined by mixing a special solution (buffer solution) with soils and measuring the change in pH. This test is labeled "Lime Index" (also called "SMP Buffer pH"). Lime requirements are calculated on the basis of change in pH of the buffer solution.



Edited by - Sag...again on 10/03/2002 10:46:25

RE: Just got soil test back ,need help!
 

Sag; I understand what you are saying and I agree with it. The high buffer value is possible (adding a fixed quantity of standard base solution and measuring the final pH) but is much higher than I've seen with a soil pH of 5.1. My charts do not even go above a pH of 7.0. The lime recommendation is less than a ton/acre at that pH (7.0).

This definitely brings to light the problems of someone trying to use a simple pH meter to determine lime needs. The ion exchange capacity of that soil must be almost zero. I would also question the fertility levels in the soil even if the pH is corrected. A final point is that no one ever mentions the agricultural index of the lime. This could be an important factor in reaching the target pH if large quantities of lime are required.

Dan O.

RE: Just got soil test back ,need help!
 

Dan, ???????

HIs (FlDeerman) soil buffer value is 7.6 (not a pH)

His soil active pH is 5.1

To bring his soil pH from 5.1 up to 6.5, the test calls for 1 ton/acre of lime.

As an example: A mineral type soil with a pH of 5.5 and a "Lime Index, SMP buffer pH value" of 6.4, would require 7 tons/acre lime to bring the active soil pH from 5.5 up to 6.5.

Yes, a buffer value of 7.6 would be off the charts for the Midwest, NE, or most of Canada, .... but Florida, ??????? we should be that lucky, but, Florida most likely has to fertilize alot more than we do. ???????

Edited by - 1sagittarius on 10/03/2002 21:07:57

RE: Just got soil test back ,need help!
 

Silly me,I thought this would be a simple question.I didn't know I needed a degree in chemistry.I talked to my Extension Service and she put it in plain english.Up where I hunt the soil doesn't leech that bad,with the clay mix,but in my yard!!!After the last tropical storm,one hour later,all the water was gone.

Hunting is not a sport,it's a lifestyle.

RE: Just got soil test back ,need help!
 

Sag: I agree with your statement about the buffer pH being a value rather than a true pH. The measured pH is the true soil pH. We agree on the recommendations for Fldeerman (although they are not what I'm used to seeing).

But you had to throw another curve into this:
My charts show a different lime rate for the scenaro that you gave. For a buffer pH (value) of 6.4, an initial pH of 5.5, and using lime with an agricultural index of 75 the recommended lime addition to reach a target soil pH of 6.5 is 4 tonne/hectare. That's roughly equivalent to 2 ton/acre. I'd like to know where the difference is because most soil tests are in line with the OMFRA chart.

For comparison, please check figures from your chart:
Target pH 6.5, initial pH 5.5

Buffer pH Lime req (tonne/ha)
7.0 2.0
6.5 3.0
6.0 9.0
5.5 17.0


Dan O.

RE: Just got soil test back ,need help!
 

Dan, actually, the chart I was looking at is kinda confusing, it has different columns for soil types and intended next crop. And it was in english, not metric. ???

I'ld like to take a look at your table, if you could email it too me???



Edited by - Sag...again on 10/04/2002 12:03:17

RE: Just got soil test back ,need help!
 

Sag; I'm packing to go up north to plant a few hundred trees right now and my scanner is down. As soon as I get back I'll type up the table and send it to you.

Dan O.

RE: Just got soil test back ,need help!
 

Well while we are at it let me throw another question to you.I took the soil sample in one county then had it mailed to my home in another county,does this matter and are they trying to match the sample with my area(or zip code)?
I don't think the lady at the extension service knew much about planting clover,she told me to put 10-10-10 on it.Does this sound right?I used 4-12-12 on it.

Hunting is not a sport,it's a lifestyle.

RE: Just got soil test back ,need help!
 

FlDeerman; what were your soil test results and fertilizer recommenadtions?

Sag; there is no email address attached to your profile.

Dan O.

RE: Just got soil test back ,need help!
 

[email protected]

Thanks Dan.

FlDeerman, 10-10-10 is ok, general purpose fertilizer, you normally can't go wrong using it. 4-12-12 would be a bit better for legumes/clovers. I use a locally available 8-20-28. But, if your soil test said you need 80 lbs of phosphorus, and 80 lbs of potassium per acre, you would need to put down ...

800 lbs of 10-10-10, or

667 lbs of 4-12-12, or

<400 lbs of 8-20-28

Its good to keep the quantities in mind when figuring the work/cost/time involved. FWIW

RE: Just got soil test back ,need help!
 

It says I need:60 lbs of Phosphorus,160 lbs of Potassium,0 lbs Nitrogen.

Hunting is not a sport,it's a lifestyle.

RE: Just got soil test back ,need help!
 

To put on the 160 lb of required Potassium you'll need to apply 1600 lb. of 10-10-10. That will mean over applying 80 lb. of Phosphorus and 160 lb. of Nitrogen. Some Nitrogen is good as a seed starter but the excess helps the grass more than the clover. You'd be closer to recommendations using a fertilizer with higher P & K numbers and a lower first (N) number.

Dan O.

RE: Just got soil test back ,need help!
 

Dan is absolutely right. At an area feed mill I did see some 50# bags of 0-0-46 potassium, and 0-42-0 phosphorus (or similar), so it is available. You can mix/put down, what ever fertilizer blends you have locally available to get as close to the recommended applications of P & K as you can. Trick would be to do it with as little Nitrogen as possible, at this time.

RE: Just got soil test back ,need help!
 

Table 1. Soil pH Recommended for Various Crops on Various Soils.
Mineral soils with subsoil pH
Organic
Crop > pH 6 <pH 6 soils
------------------------------------------
--------- pH ---------
Alfalfa 6.5 6.8 5.3
Other forage
legumes 6.0 6.81 5.3
Corn 6.0 6.5 5.3
Soybeans 6.0 6.5 5.3
Small grains 6.0 6.5 5.3
Other crops 6.0 6.5 5.3
-----------------------------------------
1 Birdsfoot trefoil should be limed to pH 6.0.

Soil pH should be corrected by liming when the pH in the zone of sampling falls 0.2 to 0.3 pH units below the recommended level. The rates of application given in Table 2 are based on the lime test index obtained using the SMP-buffer lime requirement test and are applicable to an 8-inch depth. For no-till and established forages, lime recommendations are based on a 0- to 4-inch depth, so the rates of application should be one-half the values given in Table 2. These rates are for agricultural ground limestone with a neutralizing value of 90 percent. They should be adjusted if other types of liming material are used. To adjust for a liming material with a different neutralizing value (nv)., multiply the lime recommendation given in the table by 0.90 and divide by the new neutralizing value.

Example: Lime recommendation = [(tons per acre x 0.90) / 0.80] if nv is 80 percent.

Table 2. Tons of Agricultural Limestone Needed to Raise the Soil pH to the Desired pH Level Based on the SMP Lime Test Index and an Incorporation Depth of 8 Inches.
Desired pH levels
__________________________________________________ ___________
Lime
test Mineral soils Organic soils
--------------- ---------------
index1 6.8 6.5 6.0 Soil pH 5.3
--------------------------------------------------------------------
tons agricultural limestone/acre2 tons/acre
68 1.4 1.2 1.0 5.2 0.0
67 2.4 2.1 1.7 5.1 0.7
66 3.4 3.0 2.4 5.0 1.3
65 4.5 3.8 3.1 4.9 2.0
64 5.5 4.7 3.9 4.8 2.6
63 6.5 5.6 4.6 4.7 3.2
62 7.5 6.5 5.3 4.6 3.9
61 8.6 7.3 6.0 4.5 4.5
60 9.6 8.2 6.7 4.4 5.1
-------------------------------------------------------------------
1 Lime test index is the SMP buffer pH x 10.

2These values are based on agriculture limestone with a
neutralizing value of 90 percent (Indiana RNV = 65, Ohio TNP = 90+).
Adjustments in the application rate should be made for liming
materials with different particle sizes, neutralizing values and
depths of incorporation

The relative availability of the liming material is also affected by the lime particle size. For information on adjusting lime recommendations because of differences in lime particle size, see in-state publications.

Lime rates also should be adjusted for other depths of incorporation. To adjust for other depths, divide by 8 and multiply by the new incorporation depth.

Example:Lime recommendation = [(tons per acre / 8) x 10] if incorporation depth is 10 inches.

Lime recommendations (LR) are calculated from the lime test index (LTI) for mineral soils and the soil pH for organic soils using the following formulas and rounding to the nearest tenth of a ton:

Mineral soils
to pH 6.8: LR = 71.4 - 1.03 x LTI
to pH 6.5: LR = 60.4 - 0.87 x LTI
to pH 6.0: LR = 49.3 - 0.71 x LTI
Organic soils
to pH 5.3: LR = 32.9 - 6.31 x soil pH

These rates should raise soil pH to the desired pH level, but the exact pH is not always achieved. Applications of less 7, than 1 ton/acre often may not be practical and will not appear in computer-generated recommendations. When the recommendation is for 2 tons/acre or less, the application can be made any time in a cropping sequence. When the lime recommendation exceeds 4 tons per acre, apply the lime in a split application - i.e., half before plowing and half after plowing. Do not apply more than 8 tons of lime in one season. Large applications of lime without thorough mixing may cause localized zones of high alkalinity, reducing the availability of some essential nutrients. If the soil test indicates more than 8 tons per acre are required, retest two years after the application to see if more lime is needed.

Surface applications of urea forms of, N fertilizer are not recommended on fields where lime has been surface applied recently. The potential N loss by ammonia volatilization is high when urea reacts with unincorporated lime. Urea forms of N should not be surface applied within one year of the lime application. Surface applications of ammonium nitrate, ammonium sulfate, or injected 28 percent N or anhydrous ammonia are preferred when lime is not incorporated.

WEAKLY BUFFERED SOILS
Because sandy soils are often weakly buffered, there is concern about lime requirements determined by the SMP lime test. These soils may have a soil water pH below the desired pH range for optimum crop growth but the lime index test does not indicate a need for lime. This occurs because weakly buffered soils do not have sufficient capacity to lower the pH of the SMP buffer solution. When this situation occurs, growers may want to consider using 1 ton of lime per acre when the soil water pH is more than 0.3 pH units below the desired soil pH and 2 tons per acre when the soil water pH is more than 0.6 pH units below the desired soil pH.

RE: Just got soil test back ,need help!
 

Sag; you just threw another curve. Based on your info for weakly buffered soils >.6 below the optimum pH FLdeerman needs to add 2 tons of lime. It's interesting information; I've just got to get the columns to line up.

Dan O.

RE: Just got soil test back ,need help!
 

Ok Dan and Sag lets keep this simple.I can get some 0-20-20 in 50 pound bags,think that will work?I'll check on the other mixes.

Hunting is not a sport,it's a lifestyle.

RE: Just got soil test back ,need help!
 

Dan, Yeah, that didn't cut and paste too well. What I found interesting was the total separation between mineral and organic type soils. It seemed organic type soils allowed for a lower pH???

FlDeerman, simple is very good. 0-20-20 would be perfect.

RE: Just got soil test back ,need help!
 

Fldeerman; I believe you can get away with 800 lb of 0-20-20. You'll be adding extra phosphorus but it won't hurt the clover.

You need to look at sag's info though. It says you should add lime add 2 tons per acre. The extra won't hurt when you're under aiming the pH at 6.5. It will actually give you a longer neutralizing effect. You may not have to add more lime for 5-10 years.

Dan O.

RE: Just got soil test back ,need help!
 

I've got the lime part down and now I know how to add the rest.I have to do this with a hand and push spreader so it will be done a little at a time.I'm going to add each at the end of each season to keep my plots going.Thanks for ALL the info!

Hunting is not a sport,it's a lifestyle.