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nc-jrock
07-25-2009, 08:17 PM
I had Johndeer/Lesco do a test on some compost that a local mulch dealer has been selling for years. They misunderstood what I was looking for and this is what I got .

test-organic matter Results-35.9% organic matter

Test method-organic matter reported as loss on ignition at 440 c on oven dry (105 c) compost. Conforms to ASTM D 2974 Method C.

Is this good or bad?

I asked them what the other 64.1% of it was and they said dirt.

Kiril
07-26-2009, 10:40 AM
I asked them what the other 64.1% of it was and they said dirt.

And that is the reason why you don't ask the yahoos at Lesco for advice.

Without knowing the moisture content, which could be anywhere from 30-60% in a typical compost, you cannot know how much "other stuff" there is in it. OM% in a typical compost can range from 30-70%, ideally in the 50-60% range.

You do not go through the process of determining OM% without recording wet weight .... so the boys at Lesco have their heads up their ass.

If you know the source material used to generate the compost, then you can make a pretty good guess at what the other stuff is once you know how much moisture was present in the sample.

In the future, deal directly with the lab and leave Lesco out of it.

BTW, would be nice to have a nutrient analysis as well.

nc-jrock
07-26-2009, 11:22 AM
Kril thanks for your input.
Yes I now have the labs addy and # that lesco deals with and the reason I was there in the first place was to get a nutrient test that's why I said that they must have misunderstood me on what test I wanted.
(they did not misunderstand me they mislabbled the bag, I was trying to be nice.)
So 36% is on the low end or OM.