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Interpretation of soil & tissue test results � Help?

Posted by AltoonaPA (cristclapper@atlanticbb.net) on
Wed, Aug 6, 14 at 22:19

Interpretation of soil & tissue test results � Help?


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Interpretation of soil & tissue test results,,, Help?

Report # 1 attached:


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Interpretation of soil & tissue test results... Help?

Report # 2:


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RE: Interpretation of soil & tissue test results � Help?

My read's a little limited here as I'm unfamiliar with the test. I'll do what I can.

Recommendations:
September: Apply starter fertilizer at bag rate.

October: Apply starter fertilizer at bag rate.

Memorial Day 2015: Apply starter fertilizer at bag rate.

pH 7.5: High, but nothing unworkable. The reason why it's this high is below. However, do not lime. Lime must not touch your property as you're already showing a magnesium imbalance.

Phosphorus as P2O5 169: I disagree with their evaluation here given your pH and would really like to raise this. Recommendation for application of starter fertilizer is above. Consider a re-test using Logan next year, the numbers are easier to read and I know what their targets are. Target for a higher pH lawn of this particular...well, particulars...is around 250, and I wouldn't mind seeing 300.

Calcium 75% saturation: Optimal. No adjustment necessary or desired.

Magnesium 23% saturation: Very high. No adjustment necessary or desired. This is very out of balance and is often characteristic of using inexpensive dolomitic limestone (the $4 to $8 a bag stuff) too often. Again, stop liming if you lime. If not, you simply have a lot of dolomitic lime in your soil.

Potassium 1.8% saturation: Low. However, adding it is probably a lost cause at this point. I'd rather see saturation around 2.5%, but the magnesium is grabbing onto the soil harder than the potassium will, and K can't displace Mg very easily. Let me know if you want to try and we'll do it if so.

Trace minerals: Not tested. Your tissue test shows no obvious shortages, although iron and manganese are on the low side.

To improve the iron--and you'll need a lot of it for good green colors at that pH--I'd recommend using Milorganite as your back and budget can bear it. It doesn't interact with anything, so can go with the starter fertilizer, or separately if you'd rather. Use in May, August, September, and October will slowly (very slowly) raise your iron levels.

Since the soil manganese wasn't tested, I can't give you a recommendation on adding any.

Sidenote: Calcium / Manganese is optimal in the 8 to 10 range. Dividing yours out (3000/550) gives a ratio around 5.4.

We can't raise calcium and can't preferentially get rid of the magnesium, so we live with it for now. There are methods to abolish the magnesium, but I don't think they'll work here, and I don't want to finagle with a calcium balance that's perfect already.

Just keep in mind that excessive magnesium will make soils tight and heavy, compact easily, and water tends not to flow in easily. While generally true of even sandy soils, it just means all those are worse than a well-balanced soil of the same type would be. A very sandy soil will still absorb water fast.

To get around this, if you lime, stop (as I keep saying). Adding organic material slowly over time will help make the imbalance matter less, plus lighten and open the soil to air better. The Milorganite will assist with this, as would any other type of organic feeding.

If you wish, you can try the baby shampoo/Suave formula to lighten and open your soil a little. It'll help, but doesn't work miracles in the face of an imbalance.


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Reading...

Reading your response... And working on absorbing all the great information. (still reading) Just wanted to comment on the lime issue... No lime has ever been applies. The high pH is courtesy of municipal water I use for irrigation. I do have an injector that is calibrated to neutralize by injecting sulfuric-acid. Reading continues...


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RE: Interpretation of soil & tissue test results � Help?

September: Apply starter fertilizer at bag rate.
October: Apply starter fertilizer at bag rate.
Memorial Day 2015: Apply starter fertilizer at bag rate.

Starter-fertilizer... Got it.

pH 7.5: High, but nothing unworkable. The reason why it's this high is below. However, do not lime. Lime must not touch your property as you're already showing a magnesium imbalance.
Phosphorus as P2O5 169: I disagree with their evaluation here given your pH and would really like to raise this. Recommendation for application of starter fertilizer is above. Consider a re-test using Logan

http://www.loganlabs.com/

next year, the numbers are easier to read and I know what their targets are. Target for a higher pH lawn of this particular...well, particulars...is around 250, and I wouldn't mind seeing 300.

Calcium 75% saturation: Optimal. No adjustment necessary or desired.

Magnesium 23% saturation: Very high. No adjustment necessary or desired. This is very out of balance and is often characteristic of using inexpensive dolomitic limestone (the $4 to $8 a bag stuff) too often. Again, stop liming if you lime. If not, you simply have a lot of dolomitic lime in your soil.

Potassium 1.8% saturation: Low. However, adding it is probably a lost cause at this point. I'd rather see saturation around 2.5%, but the magnesium is grabbing onto the soil harder than the potassium will, and K can't displace Mg very easily. Let me know if you want to try and we'll do it if so.

Explain?

Trace minerals: Not tested. Your tissue test shows no obvious shortages, although iron and manganese are on the low side.

To improve the iron--and you'll need a lot of it for good green colors at that pH--I'd recommend using Milorganite as your back and budget can bear it. It doesn't interact with anything, so can go with the starter fertilizer, or separately if you'd rather. Use in May, August, September, and October will slowly (very slowly) raise your iron levels.
Since the soil manganese wasn't tested, I can't give you a recommendation on adding any.
Sidenote: Calcium / Manganese is optimal in the 8 to 10 range. Dividing yours out (3000/550) gives a ratio around 5.4.
We can't raise calcium and can't preferentially get rid of the magnesium, so we live with it for now. There are methods to abolish the magnesium, but I don't think they'll work here, and I don't want to finagle with a calcium balance that's perfect already.
Just keep in mind that excessive magnesium will make soils tight and heavy, compact easily, and water tends not to flow in easily. While generally true of even sandy soils, it just means all those are worse than a well-balanced soil of the same type would be. A very sandy soil will still absorb water fast.
To get around this, if you lime, stop (as I keep saying). Adding organic material slowly over time will help make the imbalance matter less, plus lighten and open the soil to air better. The Milorganite will assist with this, as would any other type of organic feeding.

I have one additional bag of iron-sulfate… Okay to apply now? Then continue with Milorganite?

If you wish, you can try the baby shampoo/Suave formula to lighten and open your soil a little. It'll help, but doesn't work miracles in the face of an imbalance.

Love this! I read: 3-onces per 1000 square-feet. Okay?


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RE: Interpretation of soil & tissue test results � Help?

>>I have one additional bag of iron-sulfate… Okay to apply now? Then continue with Milorganite?

I want to verify that this is right:

>>Applied pelletized-sulfur at the rate is 35 pounds per 1000 square feet.

If it is, apply absolutely nothing else except the starter fertilizer until next year.

Normally, I'm always gung-ho on organic additions. In this particular instance, I don't want to add any bacterial action to the mix as this will also encourage sulfur conversion to sulfuric acid. 35 per K of sulfur is so far over the normal amounts that I don't want to give the bacteria any additional homes or oxygen until the sulfur has had time (by which I mean a good nine months or so) to dissipate and gas into the atmosphere.

Excessive sulfur has very few toxicity issues with most plants, except that the pH will take a tumble. That causes its own issues as the soil bacteria you have (had) were used to your pH. Those need to repopulate, and the pH will just keep adjusting.

Seeds don't grow well in high-sulfur soils, so you may find any reseeding in your lawn is not going to go perfectly.

>>Explain?

Again, this depends on that sulfur addition. My normal potassium source would be potassium sulfate, another sulfur-based chemical. We don't dare do that.

It's complicated, but ions bind to your soil (how many is measured by your CEC, or about 10 in your case--10 to 20 is considered normal). Calcium really grabs on there. Magnesium grabs on, but not as tightly. Potassium only has a weak hold.

On the acidic side, some to many of those attachment points are held by hydrogen--and that's a very weak bond. Anything can displace hydrogen.

Calcium can displace magnesium, potassium, and hydrogen. Magnesium can displace potassium and hydrogen. Potassium can only displace hydrogen. That's simplified, BTW.

In your soil, most of the space is taken up by calcium. Almost all the rest is taken up by magnesium. What little remains is currently filled with potassium.

There are no open holes, held only by hydrogen, to fill--so adding potassium is unlikely to stick. It just ends up washing through.

That having been said, it's just not that simple. Adding potassium would raise your saturation somewhat, and probably some magnesium would leave the soil bonds and form either a salt or a stable bond with something else in the soil.

So it's difficult, not hopeless, but with that sulfur addition I really can't see stressing the soil any more this year.


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Working on...

Following your recommendations. Stay tuned... And thanks!


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RE: Interpretation of soil & tissue test results � Help?

The Agri folks charge $28.00 for soil and tissue testing... And the Logan folks charge $55.00 for their soil and tissue testing. Are the Logan reports worth the additional charge?

This post was edited by AltoonaPA on Sun, Aug 31, 14 at 18:20


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RE: Interpretation of soil & tissue test results � Help?

I don't know the quality of the response from either, so can't easily answer that.

Usually? Tissue testing isn't necessary--soil testing is enough to get everything balanced, so the base $25 soil test is good enough.

I know of some people who are fans of tissue testing, but my take on it is that there are exactly two places to gather resources--air and soil. Air moves and changes. Knowing what's in the soil and what the plant wants solves the rest of the problem.


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RE: Interpretation of soil & tissue test results � Help?

As I understand it the reason for the tissue testing is to correlate plant uptake with soil nutrients. If you were a farmer trying to get pecans year after year instead of every other year, then do the tissue testing.


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