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ICT Bill
11-22-2008, 10:08 AM
We have been in trials this year with lots of franchises, was on a call from one this week. They used their typical program in the front yard and an organic one in the back yard, many sites

They wanted to test efficacy and overall health, color, turf density and so on. They used an extracted, brewed and our instant compost tea. six applications were applied through the year. soil tests were taken at the beginning of the year and then again recently

On the compost tea sites the only thing that was used was compost tea, no compost or other nutrients. On one site they used only compost and no teas, anyway.

On the compost tea sites the CEC went up significantly on the compost only site it basically stayed the same. On our instant compost tea site the SOM went from 3.9 to 7.2, this was similar to all types of tea the SOM almost doubled in every case, the SOM of the compost only site crept up slightly.

My question is: Is there a simple explanation to the doubling of the SOM on the compost tea sites, I can't think of one.

These guys are very professional and qualified and have been in the industry for many years, I doubt the soil test were done incorrectly. the similarity of the results over many sites was unquestionable

signed :confused:

BTW, visually the compost tea sites were close in color, a little less density, basically a close second to the NPK applications but that is to be expected, especially the first year

44DCNF
11-22-2008, 10:38 AM
Clippings and leaves breaking down better under the tea and being reincorporated to the soil rather than blown or dissipated away into the atmosphere as chaff? Worms bringing organic matter into the picture? Very interesting! I always see small twigs pulled into the openings of worm holes in the spring. If they feed on surface debris and return to their tunnels to deficate........more matter in the soil. Anything in the reports on worm numbers or activitiy and how were clippings and leaves handled on these trials? And why limit it to worms, aren't all the microbials doing the same thing in one way or another? As they multiply and pass on they are adding organic matter too, are they not?

growingdeeprootsorganicly
11-22-2008, 10:43 AM
[QUOTE=ICT Bill;2614410 On our instant compost tea site the SOM went from 3.9 to 7.2,[/QUOTE]


first guess....magic?

NattyLawn
11-22-2008, 11:01 AM
The organic matter jump is a little unbelievable, especially applying tea or ICT only. Did they really apply compost 6 times in one season with little organic matter jump? At what rate was compost applied?

There are so many variables that could skew results here, so simply doing traditional in the front (probably trying to keep them looking as green as possible for the homeowner) and tea out back isn't really a good test. Do the front and back get the same amount of sun? Traffic? Tree cover/shade? Irrigation? When were the soil samples taken? Before or after application/How soon? How deep were the cores pulled for the sample? 6 apps of compost with cores pulled at 3-5 inches should have given you a decent boost in SOM. Source of compost for the lawn and tea?

A lot of variables.....

ICT Bill
11-22-2008, 11:52 AM
The organic matter jump is a little unbelievable, especially applying tea or ICT only. Did they really apply compost 6 times in one season with little organic matter jump? At what rate was compost applied?

There are so many variables that could skew results here, so simply doing traditional in the front (probably trying to keep them looking as green as possible for the homeowner) and tea out back isn't really a good test. Do the front and back get the same amount of sun? Traffic? Tree cover/shade? Irrigation? When were the soil samples taken? Before or after application/How soon? How deep were the cores pulled for the sample? 6 apps of compost with cores pulled at 3-5 inches should have given you a decent boost in SOM. Source of compost for the lawn and tea?

A lot of variables.....

I agree with the variable statement. I am just wondering if anyone else has had similar results. The extracted tea went from 3.6 to 7.0 and the brewed went from 3.8 to 6.9. The composted site had 2 applications spring and fall.

One site that had tea had never been fertilized in the 16 years that the person lived there, these were all employees of the company in the trial. The sites are all over a large area, different neighborhoods, different age of subdivisions, etc

The person who did the physical gathering of the soil at the sites is a very respected well known professional that has been in the industry for over 25 years. The consistancy of the results across all of the tests leaves out operator error

I can't explain it either, root mass maybe. I would expect some increase but not almost doubling.

maybe the testing procedure at the lab was not right, if that was the case it is not right on all of them. who knows, I will talk to them again next week and go over the numbers again

Tim Wilson
11-22-2008, 12:05 PM
I’ll take a whack at a theory. When the SOM testing is done the organic matter which can be comprised primarily of humic substance needs to be isolated from other material like sand, clay and other soil components. This can be done chemically or with heat.

When compost tea was applied to the areas where the tests were conducted, the higher microbial population, resultant from brewing CT and from the combined microbial inoculants converted older existent non-decayed matter into covalent and noncovalent bonded material. Additionally microbes died and consumed each other creating these humic materials. This humic substance is what shows up in the testing method. We would assume that the identical extraction and testing method was used across all plots, so might conclude that in the case of the compost applied that the degradation and microbial activity is occurring at a more even natural pace and the humic substances may not reach the same levels for an extended time.

[Because energy=energy the foodstock inputs = large volumes of microbes = humus]

It would make for an interesting study to follow these plots over a number of years with some manipulation of inputs. (e.g. no application of CT to part of high SOM area & continued applications to part)

One needs to also consider other variables which may be at play as pointed out by Natty BUT....

It does seem to support the theory that one can raise certain plants with CT and small amounts of matter or foodstock alone.

We have done this successfully in a greenhouse for a number of years.

DUSTYCEDAR
11-22-2008, 12:13 PM
DID THE TEST TAKE PLACE IN AREA 51 BILL?
just couldent help myself
are they going to keep testing next year also? in the same areas.

JDUtah
11-22-2008, 12:30 PM
Well thought out Tim.

I was crudely wondering something similar (If I understood what you said)

If the lab used an extraction method to test SOM, would this % include the lignin and cellulose molecules found in organic matter? Do the solvents that are used in the extraction technique properly break them down? I assume the heat technique might not have such limitations (if that even is a limitation)?

If they used extraction, and the above is true- that extraction does not include more complex and stronger bound organic molecules, perhaps the microbes converted these molecules into more 'testable' forms in the respective test plots?

If that is the case, it would be interesting to see what happens to the SOM over a period of time, like 5 years. Will the SOM diminish to more equilibrated numbers after some time? Stay the same? Continue to increase?

Bill,
Interesting stuff. Do they know what SOM test the lab used? Hopefully they plan on testing it for another year or two? Thanks for bringing the info!
David

Oh,
Another factor to consider is if the plot soil was prepared before hand? Was the soil ammended within the last couple years? With what?

Also fallen leaves? The microbes could have broken them down and significantly incorporated them into the soil before they were removed (worms help)? This could also contribute to an SOM increase (even as a spike?) in the microbe sprayed areas.

Lol, if this isn't a post full of speculation I don't know what is. But questions are what bring answers huh? Man I am excited to get started with my own stuff (testing/work). Anyone have 25 grand sitting around that they want to invest? lol (before I'm told I can start for less, please understand I have a very specific plan of things)

'What if' rant over…

growingdeeprootsorganicly
11-22-2008, 01:53 PM
need to know what type of om test used?

Tim Wilson
11-22-2008, 02:13 PM
If the lab used an extraction method to test SOM, would this % include the lignin and cellulose molecules found in organic matter? Do the solvents that are used in the extraction technique properly break them down? I assume the heat technique might not have such limitations (if that even is a limitation)?

If they used extraction, and the above is true- that extraction does not include more complex and stronger bound organic molecules, perhaps the microbes converted these molecules into more 'testable' forms in the respective test plots?


As far as I know some chemical extraction techniques can result in cross over contaminants; silica can be dissolved to be included with the organic fractions in the testing as well as some components of non degraded organic material can be dissolved and mixed with the humified matter in terms of the test results.

My understanding with the heating method is that the material is weighed, then heated to the extent that all carbon components are ‘burnt off’, the material is weighed again. The difference represents the humic (SOM) content. Please correct me if I am wrong on this. It would seem on the surface that the heating method may be less likely to be in error, however there have been recent advances in extraction techniques which are reputed more accurate.

Because the same method was presumably used on all plots, it is the comparison which is significant.

Kiril
11-22-2008, 04:36 PM
Yes, those numbers are hard to believe.

Natty pointed out some very good possible causes for discrepancies, and Tim covered the CEC part of it,

I would also question experimental design & methodology. I hesitate to compare one site to another and say look, site A did much better than site B.

A more appropriate design would be to eliminate as many of the unknowns as possible by doing the experiment on the SAME lawn, under the same environmental conditions. Split the lawn into a grid of 4 squares and test each method (control, ct, compost, conventional), and do that on multiple properties.

As the "experiment" stands now (per information provided), I would not put any faith in the results beyond mere curiosity.

ICT Bill
11-22-2008, 04:53 PM
Yes, those numbers are hard to believe.

Natty pointed out some very good possible causes for discrepancies, and Tim covered the CEC part of it,

I would also question experimental design & methodology. I hesitate to compare one site to another and say look, site A did much better than site B.

A more appropriate design would be to eliminate as many of the unknowns as possible by doing the experiment on the SAME lawn, under the same environmental conditions. Split the lawn into a grid of 4 squares and test each method (control, ct, compost, conventional), and do that on multiple properties.

As the "experiment" stands now, I would not put any faith in the results beyond mere curiosity.

I guess it is an experiment of sorts. Here's the background. franchise wants to use friendlier ways to treat lawns becuase of customer demand of lower inputs and they may be able to make some money at the same time.

Being a smart bunch they say, lets test it out at the main site (where most of the brains are) and on our own lawns, about a dozen folks say yes.

They break the lawns into different applications to be tested. Some are new construction, some 2 years old, some much older. some have had their own folks taking care of their lawns for years other could care less about thier lawns and have never applied fertilizer. seems to me this is the typical customer base, very diverse.
They decided to treat the front yard with normal methods and treat the backyard with organic methods 3 compost tea methods were tried: brewed (from a local source), extracted (from 100 miles away, had to be shipped) and ours from the carton

These are very smart folks and very saavy turf and landscape people. They decided to not only look at color, density, overall appearance, etc of the turf but to soil test at the beginning and end of the year to see if there are any soil differences. They are going to expand their trials to maybe a dozen other offices next year and continue to test and observe.

I am just relaying information given to me and asking the question "why?" I do believe Mr. Tim Wilson is very close but I will ask next week on the type of testing that was done. I know for a fact the same lab was used for all testing, I have to assume they used exactly the same way to test.

Kiril
11-22-2008, 05:13 PM
As far as I know some chemical extraction techniques can result in cross over contaminants; silica can be dissolved to be included with the organic fractions in the testing as well as some components of non degraded organic material can be dissolved and mixed with the humified matter in terms of the test results.

My understanding with the heating method is that the material is weighed, then heated to the extent that all carbon components are ‘burnt off’, the material is weighed again. The difference represents the humic (SOM) content. Please correct me if I am wrong on this. It would seem on the surface that the heating method may be less likely to be in error, however there have been recent advances in extraction techniques which are reputed more accurate.

Because the same method was presumably used on all plots, it is the comparison which is significant.

From my archives.

Tim Wilson
11-22-2008, 05:35 PM
Kiril, thanks.

JDUtah
11-22-2008, 06:04 PM
Yes, thank you.

muddstopper
11-25-2008, 09:54 PM
My offhand thoughts are simply that the addition of the active microbes in the CT probably broke down the already exsisting OM faster than the microbes contained in the composted areas. I also supect that this great increase in SOM from the CT only areas will diminish over time, while the SOM on the composted only areas will increase. I am pretty sure there is already research to support my speculations, at least I think I read that somewhere.

Interesting results, but a one year test doesnt accurately reflect results of future years. The simple fact that you tested at two diffent times of the year would yield different results. I would be more interested in seeing comparisons with next years test results taken at the same times of year as the original testing, than the test results for two testings done the same year.

Kiril
11-25-2008, 10:04 PM
The simple fact that you tested at two diffent times of the year would yield different results. I would be more interested in seeing comparisons with next years test results taken at the same times of year as the original testing, than the test results for two testings done the same year.

I might also increase the testing to include environmental extremes along with "norms". However IMHO, the "experiment" is fatally flawed because there are simply too many unknowns too compare results between sites in any meaningful (statistically significant) way.

ICT Bill
11-26-2008, 08:59 AM
Interesting results, but a one year test doesnt accurately reflect results of future years. The simple fact that you tested at two diffent times of the year would yield different results. I would be more interested in seeing comparisons with next years test results taken at the same times of year as the original testing, than the test results for two testings done the same year.

I agree with the one year statement, I will be interested as well to see long term results and testing. We hope to have a copy of the testing I will post numbers when we get them.

I might also increase the testing to include environmental extremes along with "norms". However IMHO, the "experiment" is fatally flawed because there are simply too many unknowns too compare results between sites in any meaningful (statistically significant) way. Fatally flawed? a little extreme don't ja think, its just a soil test. I know you aren't saying that every soil test is fatally flawed. It is a snap shot as we all agree. They took 2 soil tests and are simply comparing the results

This area has very nice soils, I was there in the spring when tilling and plowing was going on in the fields, nice dark soil.

Hey here's a thought, and I will find out the spring test date. In the spring as soils are warming the soils are not very active. If the fall testing was done while the soil was still in the 60's or 70's would that make a difference in the SOM results? I wonder if a test right now while the soil is almost frozen would result in a low SOM number. I love stuff like this

Kiril
11-26-2008, 09:27 AM
Fatally flawed? a little extreme don't ja think, its just a soil test. I know you aren't saying that every soil test is fatally flawed.

Yes ... fatally flawed if your purpose is to compare different management methods.

It is a snap shot as we all agree.

There are some items in a soil test that are not really a "snapshot". Granted in any biological system, the state of it can change from one second to the next, and from one location to another 10mm away. However, even given the biology, some of the test results will change very little over time, which makes them less of a snapshot.

Hey here's a thought, and I will find out the spring test date. In the spring as soils are warming the soils are not very active. If the fall testing was done while the soil was still in the 60's or 70's would that make a difference in the SOM results? I wonder if a test right now while the soil is almost frozen would result in a low SOM number. I love stuff like this

I don't see why there would be any difference, assuming the soil test includes all organic matter. A more meaningful test would be to measure humic substances along with total SOM.

muddstopper
11-27-2008, 11:00 AM
Hey here's a thought, and I will find out the spring test date. In the spring as soils are warming the soils are not very active. If the fall testing was done while the soil was still in the 60's or 70's would that make a difference in the SOM results? I wonder if a test right now while the soil is almost frozen would result in a low SOM number. I love stuff like this

Soil testing for fertility issues will vary according to the time of year the samples are taken. I can only guess that this would hold true for humic substances as well. This is one reason soil testing on the same areas should be taken at or near the same time frame every year.

In a crop situation, the act of growing the crops will decrease fertility because of the amount of nutrients removed to generate the cells of the plants. When figureing nitrogen applications, the humis fractions contained in the soil are factored in to the required nitrogen amounts to apply. Plant root acids do breakdown humis releaseing the nutrients to the plants. You also have to factor in the amount of crops removed from the soil to help determine future needed imputs for future crops.

In a lawn or landscape situation, you have nutrient loss as well, altho the total amounts might not be as great if you are returning the plant clippings to the lawn. If one samples their lawn or cropland in the spring, the nutrients levels might be at the highest level of the entire year for a crop area, but at the lowest level for a lawn area. This is simply due to plant residues and just how well those residues where broken down over the winter months, or to how much of the residues where recycled to the plants growing there. Cold weather slows microbial activety and OM levels might be higher during colder months while humic fractions might be higher in the warmer months. Active plant roots will return OM to the soil during their growing and regenerative life cycle which is also usually when soils are warmer. At anyrate, there are many varibles to soil fertility during the different seasons of the year and why just one or two years soil test reports might not give you the full picture.. It takes time for applied nutrients to move thru the soil if they are just topdressed applied. Lime is one good example of this. It can take a lime application as much as 9 years to fully effect the pH in the top 6inches of the soil layer if surface applied, but can effect the top 1/2 in of the soil in a manner of days. Lots of varibles to my lime example also.

Kiril
11-27-2008, 11:31 AM
Soil testing for fertility issues will vary according to the time of year the samples are taken. I can only guess that this would hold true for humic substances as well. This is one reason soil testing on the same areas should be taken at or near the same time frame every year.

Agreed. When comparing test results, ideally the samples should be taken in the same area and environmental conditions as your baseline.

Also, good points on nutrient loss. This will also apply to SOM as it decomposes since much of the carbon will be lost from the system in the process. I should have read Bill's question closer, saw temp, missed time. :hammerhead: