Subject: Re: Proper compost

From: Elaine Ingham <[email-masked]>
Date: Tue, 5 Nov 2002 14:16:55 EST

The definition of properly composted material, when applied to thermal
compost, is that it has reached temperature throughout the material for long
enough that weed seed, human pathogens and most of the plant pathogens and
pests have been killed.  There should be no E. coli in properly composted
material.

If someone SAYS material was properly composted, and the material has E. coli
in it, then it is not properly composted material.  Simple logic.

Most people mean a compost is finished if it has heated and come back down to
ambient temperature.  Does that guarantee that appropriate temperatures were
reached, for long enough, through the whole pile?   Long enough to kill the
E. coli and other human pathogens?

It should mean that.  But if people are calling a compost finished, and the
compost still has E. coli in it, then the compost was not truly finished.
It's still just partially decomposed organic matter.

Because organic matter stands in a pile and heats a bit, does that make it
compost?   No.  Did the composting process get started?  Yes, but it was not
allowed to finish.  If you leave organic matter in a pile long enough, will
it become compost?  Sure, but when do you know when it is "finished"?

There are standards.  Excuses that because it's too expensive to turn, or
monitor, or aerate organic matter properly, and so not remove E. coli fully,
does not mean it's ok to call the material compost.  Because people are not
willing to do a proper job, does not mean that we change the definition of
compost.

Could there be categories of quality in compost?  Yes.  Especially if
composting operations are not doing what is necessary to produce compost that
is completely and correctly processed.

Data showing the amount of E. coli in compost should be necessary, along with
other chemical and biological properties, to document compost quality.

Implementation of standards remains to be seen.  But because someone calls
something good compost does not mean that it is so.  Data are required.
Properly composted material does not contain E. coli.

Does this mean most of the commercially-sold "compost" produced in the US is
not properly composted?   Yes, that's what it means.  Doesn't change the
definition of properly composted material, however.

Elaine Ingham
President, Soil Foodweb Inc.
www.soilfoodweb.com

---

From: Elaine Ingham <[email-masked]>
Date: Thu, 7 Nov 2002 13:15:52 EST

Hi Roberto -

Did I say that everyone has to test?  Please go back and read my e-mail.

When is it that you would have to test?  If you want to know whether you have
good compost.  In that case, you should test for the FULL FOOD WEB being
present, so you would know that E. coli will be taken care of, if you
maintain oxygen and foods for the beneficials to grow.  Make sure the
chemistry is correct.

However, my recent comments have been in response to the recommendation by
Wil Brinton and the Compost Task Force of the National Organic Standards
Board.  That recommendation stated that compost tea and vermicompost tea
cannot be used on food crops because of the danger of E. coli in the tea
brews.

I agree with you that organic growers should not be subject to standards that
are greater than conventional growers.  I've stated that in previous posts.
So, you really need to go to Wil Brinton, and the Compost Task Force and get
them to explain their recommendation.

My personal attitude about E.coli presence is not that you would be
"de-certified" if you have E. coli in your compost, but that you would need
to begin to work toward finding the source of contamination and removing it,
or changing your production methods to get rid of the E. coli.

We've been monitoring several composts for the last few months.  One compost
started at 44,000 E. coli per gram of "compost" (by my definition, not a
proper compost, right?).

By keeping that compost pile aerobic (pile less than 6 feet high, moisture no
higher than 50%, and NOT turned, because that destroys the aggregate
structure built by the microorganisms growing in the pile), the numbers in
that pile have steadily declined, and now are at an average of 42 E. coli per
gram.  This is well below the regulatory level for CONVENTIONAL growers in
most states, as I understand the regs.

We made tea from the "compost" mentioned above when that compost was high in
E. coli.  We used a 100 gallon Earth Tea Brewer tea maker machine
(www.composttea.com), AND added MOLASSES into the tea brew.  The number of E.
coli in the 24 hour, aerobic compost tea was 2.7 E. coli per ml.  This is
well below irrigation water levels that growers can put on their crops.

So much for those people that say molasses causes a bad set of bacteria to
grow.  The organism/aeration conditions of the brewing process reduced E.
coli to nearly un-detectable levels.

What if there were fewer E. coli per gram in the compost to start with?  In
other studies we have done, E. coli was not-detectable in the tea after 24
hours when using the 100 gallon Earth Tea Brewer.

Do ALL of the compost tea machines on the market right now reduce E. coli in
a 24-hour aerobic tea brew?

Apparently not, since the Growing Solutions 25 gallon compost tea machine
used by BBC Lab had significant levels of E. coli at the end of a 24 hour tea
brewing cycle when using sugar, molasses or barley malt.  Their data have
been published in the papers from May 2002 Biocycle meeting  (please note
that this is not a peer-reviewed scientific journal, so you need to be more
critical of the methods used than you would be for peer-reviewed papers).  I
believe the paper can still be downloaded from the Biocycle website.

BBC Lab claimed that the tea brew maintained aerobic conditions throughout
the production cycle.  But they only present data in their paper for one of
the many tea brews performed.  Either they only monitored oxygen for ONE tea
brew, or they are trying to say that oxygen use remained the SAME for all the
different tea brews they performed.

There is a difference in how the organisms respond to molasses versus white
sugar, or barley malt, or humic acids, or fish.  When we run different food
resources in the tea, we get different oxygen responses.  What happened to
the oxygen data for the other tea brews, if BBC Lab in fact monitored oxygen
in all those runs?  They claim their tea brews stayed well-aerated and that
thus E. coli grows aerobically.  But where are the data to support their
claims?

In fact, if you monitor oxygen, maintain aerobic conditions, and have the
foods to grow the competitive, inhibitory and consuming organisms, E. coli
numbers will be reduced.  At least, with everything that we are doing, that's
what we see.

A note of caution, however.  We just finished a tea run where we started with
STRAIGHT manure, and ok, if you have an outrageous number of E. coli in the
starting materials (in the millions per gram), you can't reduce the E. coli
to even close to safe levels in 24 hours of aeration.

What does that mean for growers?  Don't make MANURE tea and out it on
something you are going to eat anytime in the near future.  But we already
knew that manure isn't compost.

But, we put compost with low numbers of E. coli in the 5 gal KIS tea brewer
(www.simplici-tea.com), and E. coli was undetectable after 12 or 22 hours.

So, we now know that two tea brewers WILL REDUCE E. coli numbers; the Earth
Tea Brewer, and the KIS tea brewer.  We know that the Growing Solutions
machine will NOT reduce E. coli numbers, based on the data that the
manufacturer of the machine claims is correct.

So, the current NOP regs say that you have to perform the composting process
correctly.  If you do, then there is every likelihood that you will drop E.
coli down to reasonable, and perhaps undetectable levels.  So, use properly
composted materials and things should be fine.

Experience says that if you do proper composting, E. coli will be gone.  Then
there's the real world, where less-than-perfect conditions prevail, and
maybe, some E.coli will escape.  Our data are saying that's ok if you have
the right machine, and conditions are maintained correctly.

The NOP regulates the PROCESS.  So, for compost tea, the PROCESS should be
regulated.  Use, or make, compost tea machines that will properly maintain
aeration and the growth of the full food web set of bacteria, fungi and
protozoa.

But, as I said before, what if you want to know FOR CERTAIN?  Then you have
to test.

Did I say everyone has to test?  No.  If you do the process correctly, then
you should be fine.  Tests are necessary if you want to know for certain.

I don't know about you, but I like solid data.

Elaine Ingham