Manganese uptake, calcareous soils.

JD3000

JD3000

Most well-known member
Location
Columbus
Having trouble with Mn on many trees and shrubs. High end residential settings so expectations are high but so is my pricing. Here's some facts:
85 soil samples taken over past couple years, roughly 50 square miles covers most of them.
Average CEC 16
Average pH about 7.6
Average Mn per acre about 11 lbs
Average Fe /acre about 115 lbs
Average Ca/ acre about 5200 lbs
Average P depends on testing area. About 163 lbs/acre from beds but only 28 lbs/acre from turf areas where many trees are surrounded.
I have numbers for all other tested nutrients and base saturations as well as mean, median, standard deviations etc typed up in a basic report so hit me up if you want one emailed.
Typical suburban crap soil, compacted, inverted, trucked in, and poor drainage/aeration.

Been reading as much as possible about Mn, often from the agricultural fields as I cant find much from hort and forestry sources. From what I've read, Mn availability starts reducing at pH in the high 5's for many acid prefering plants (red maple, flowering dogwood, etc) which can also be exasperated in calcareous/active lime soils. Furthermore, not all chelates, ligands, and inorganic salt sources are particularly well available in the soil types I'm dealing with.

I havent run lime or neutralization tests until this week but Dr Darrah at CLC labs showed me a trick for speculating about having calcareous soils or not. pH over 7.5, Ca over 5000 lbs/acre, and a CEC over 15. About 75% of samples meet this figures and the other quarter is damn close. The few tissue tests that Ive run have been sufficient to excess for most nutrients with very high Ca and low to very low for Mn.

Water source for the fert tanks is kept at pH 6 to 6.5 as it's nursery water that has a sulfuric acid injecter on it. I havent run tests for carbonates or bicarbonate yet. Generally turn the fertilizer off before filling as the N is mostly nitrates and I dont want the leaching and potential alkaline reactions from a nitrate source. Considering increasing the acidity when filling tanks.

What I've been using recently:
Ammonium sulfate (soluble form) as an acid N source at 5 to 10 lbs/100 gl. I've gotten away from Doggetts and such but the newer liquid slow release N sources are better in the tank and I may add a 28 0 0 with 60% SRN and cut the AmSO4 in half.

Brandt Mn EDTA 13% at 2.5 lbs/100 gl
From what Ive read, edta has the highest stability constant at higher pH BUT it has a higher affinity for Fe and can jump ship from Mn given enough time. Main Event Mn, which is a citrate source, was really hit or miss for me, mostly misses. Also have a bag of Brandt Mn 15% lignosulfonate sitting around but have read it and glucoheptonate forms wont be stable in limey soil.

Apex 10 at 10oz/100 gl. 12% humic substances with 9% humic acid. Ive read that humic substances can form chelates/ligands with the metals so hoping it may help. Non aerated compost tea is an easy alternative as we have tons of compost here.

Sulfur applications to beds in the autumn at 5 to 10 lbs/1000 sq ft. Part of a long term acidification program to neutralize lime rather than a single heavy application.

What else has anyone found success with in similiar soils? Injecting or foliar Mn is a band aid because Mn is largely immobile so roots will still be starved for Mn.

Good reading on the topic(s)
"Is reducing soil pH possible?" by F. Mancino.
"Managing Mn deficiency in nursery production of red maple" by J. Altland
Many papers out there about chelates and ligands as it relates to stability and availability.

That's a lot to type. Please help!
 
Well if your soil pH is 7.6 there is not much chance for any available manganese.

Manganese occurs in three primary states MN2+, Mn3+ and Mn4+. Mn2+ is the form taken up passively by plants. When Mn2+ is available in aqueous solution but rapidly oxidizes to 3+ and 4+ states of insoluble oxide materials.

Thus in high pH soils (above 6.7) manganese is largely unavailable.

SO what to do, well chelated Mn is one option though timing of folair application needs to be done as leaves are unfurling. Spraying the underside of leaves while stomata are open and adding some urea to the solution is the best option. Treatment of soils with chelated Mn (whether it is EDTA or not) is not going to work well.

With this in mind planting programs should be designed to avoid manganese dependent species such as Acer rubrum, many of the white barked Betula, and the many cultivars of Acer freemanii.
 
Oh and your fertilizer recommendations are likely BS as they are developed under an agricultural regime.
 
So is there no necessary role for Mn in roots?

Where I have had much better success are situations where we can expand the mulched area underneath the canopy and apply higher Mn and S. This is especially true when I can stir and mix compost with an air spade. Re-testing has shown lower pH and higher available Mn. Wondering about the role of soil microbes in this case where the OM and structure have been improved.
Havent been able to do much with turf areas and higher S applications to turf are generally frowned upon.

We could almost start a whole new thread dedicated to dreadful plant selection by designers and LAs but I'm stuck with existing trees and their maintenance.
 
Not recommendations at all, things that Im trying. But yes, based on agricultural banding and localized (hopefully) acidification.
I'm here to learn about the subject not play expert by any stretch of the imagination

EDIT: Emphasis on NOT recommendations. I'm very much open to them though.
-JD
 
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Manganese has multiple roles and likely many unknown roles. Mn is important in electron transport chains in particular.

I am not surprised that a well composted soil is showing more available Mn. MN that has not been oxidized is what we are looking for and rotation through the soil food web is highly beneficial
 
JD3000 said:
Hard part can be convincing folks to lose some of their damn precious lawns but it depends on the customer.
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I know what you mean. Not sure what species you are dealing with (as the pH needed depends on the trees) but if you can, promote, promote, promote mulching as much as possible of root zone. This not only will help acidity in the soil, but also get the soil back to natural "forest" conditions that will drastically improve the soil and thus tree health.
 
Acidity is not always the issue. When we look at soils in the traditional physical and chemical sense than pH is important, when we add in biology we are almost lost.

I read yesterday that we know less about soil than we do about the ocean depths (and I even have a book signed by Don Walsh of Trieste fame when we were in the arctic together).

It seems that we need to try to create soil conditions as close as possible to natural habitiat conditions as possible. Thus acidic forest soils for maples and flood plain soils for Phytolacca diocea. Soils and organic matter are different form tree to tree. I have seen areas this summer where Autumn Blaze Maple fail while Burr Oak thrive.
 
mrtree said:
Acidity is not always the issue. When we look at soils in the traditional physical and chemical sense than pH is important, when we add in biology we are almost lost.

I read yesterday that we know less about soil than we do about the ocean depths (and I even have a book signed by Don Walsh of Trieste fame when we were in the arctic together).

It seems that we need to try to create soil conditions as close as possible to natural habitiat conditions as possible. Thus acidic forest soils for maples and flood plain soils for Phytolacca diocea. Soils and organic matter are different form tree to tree. I have seen areas this summer where Autumn Blaze Maple fail while Burr Oak thrive.
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I totally believe it.. Have a property where the undisturbed forest has no noticeable nutrient and soil issues but the edges and disturbed landscape areas are a mess. Structure, texture, chemisty, and biology all different 30 yards away. Native forest beech stands are great, planted beech are a train wreck of disorders.
 
Zacchaeus said:
I know what you mean. Not sure what species you are dealing with (as the pH needed depends on the trees) but if you can, promote, promote, promote mulching as much as possible of root zone. This not only will help acidity in the soil, but also get the soil back to natural "forest" conditions that will drastically improve the soil and thus tree health.
Click to expand...
Most of Ohio is hardwoods (oak, maple, hickory, beech, few ash left)on the east, flatter cultivated plains to west. Generally more acidic and sand stone based on east, more alkaline to west. Exceptions in areas of course.
 
Forest soil as an innoculant?

Just put some down from a native beech grove for a remediation project on some weeping european beeches in decline. Compost stirred and added the forest soil at same time. Figured it couldnt hurt and I generally dont buy the commercially available innoculants.
 
I think that inoculating a soil with "good" soil is an interesting idea with few draw backs but I wonder if expecting a poor soil to support good innoclum is realistic? Would a soil capable of supporting the soil life we want not already have most thins without us adding a shovelful? I think we need to think basics first, structure and texture, organic matter than the little things. I suppose nobody has checked out pseudoscorpions but they are in the soil and a good indicator of soil health, we cannot just add them to soil. As adjusted from Shigo, we need to think in soil time.
 
Weeping beeches in this case were salt affected from snow removal and deicing salts, mostly halite. Led to borers and some stem cankering. Soil tested quite well with exception of Na. Aerated root zone, ammended, put down some gypsum, and increased irrigation to hopefully leach Na. Need to figured out some sort of buffering system to keep snow melt and salt from becoming so problematic again...not sure how yet as its downhill from the asphalt drivway and garage area
 
The concept of shifting the buffering system is a good one. Once again, soil organic matter (and the attached carboxylic anions) will hold some Mn cation, as well as Ca cation, slightly lowering the pH, which is good. Others have mentioned chelators, which is good.
The trick is that you don't want to raise the salt index while shifting the buffer system! Also as noted before, Mn occurs in various valence states depending on the redox conditions in the soil. Yes, some of the wood decay fungi and pioneer hyphomycetes are pretty good at taking up Mn cation and sometimes sequester manganese dioxide as crystals in the tonoplast. So, soil organic matter will help that as well. It is tough, I know.
 
Iron used to be tough to correct but EDDHA and more OM have helped a great deal. Mn has been quite difficult here
 
Also Mn limitations or deficiencies have been misdiagnosed as Fe for some time here, myself included. Lots of birches and pin oaks may look like Fe issues here but Mn is far more often the limiting nutrient. This speaks for my part of central Ohio so other places can certainly be different.

Wondering if a tissue test showing adequate micros but also high to excessive Ca and sometimes Mg can be misleading because the lime perhaps neutralizes the metals? Lime induced deficiency despite adequate Mn or Fe on the tissue test?
Dont know for sure
 
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