>
>Date: Tue, 28 Mar 2000 19:40:22 -0500
>From: Grace Gershuny <graceg@ConnRiver.net>
>Subject: Re: Organic or not?
>
>As far as I know, you can use any dairy manure for compost, although some
>programs are more restrictive about compost feedstock from non-organic
>sources. The effluent from a digester might still be considered "raw
>manure" for the purposes of certification, but I'm not sure how this is
>being handled by certifiers.
>
>As a general note, the current proposed rule would allow only compost made
>according to NRCS practice standards, which only apply to on-farm
>composting. Someone has already pointed out that this would make
>vermicomposting unacceptable, but it also doesn't allow for use of compost
>made by food processing operations or various commercial compost
>operations, unless they start calling themselves farms.
I am not so sure about this, as the note to the rule suggested otherwise:
http://www.ams.usda.gov/nop/rule2000/production_handling.htm
"(2) Nonorganic Plant and Animal Waste Materials. The first proposal
permitted the use of any uncomposted plant or animal wastes. It also allowed
use of composted plant or animal wastes obtained from nonorganic sources,
such as commercial compost products. Several consumer and environmental
groups objected to permitting the use of plant or animal wastes from
nonorganic sources. Such materials, they argued, could potentially contain
residues of prohibited substances that could compromise the integrity of the
organic farm system. However, off-farm plant and animal wastes from food
processing, municipal yard waste facilities, and other sources are used
extensively in existing organic operations and are generally permitted by
organic certification programs. Bone meal, fish meal, and seaweed meal are
also commonly used as organic farm inputs. Commercial fertilizer products
that contain mixtures of such plant and animal by-products are commonly
permitted for use in existing organic certification programs, subject to
certifying agent review. Using such organic wastes is consistent with a
system of organic production and handling, which calls for recycling organic
wastes to return nutrients to the land. We believe that concerns about
potential contaminants in plant and animal waste materials can be addressed
by the requirement in this proposal that these materials be managed in a
manner that prevents such contamination. For example, cotton gin trash that
had been treated with a prohibited substance could only be used if the
organic system plan specified composting the material before adding it to
the soil. Composting has been shown to effectively biodegrade synthetic
organic compounds, and the organic system plan could also call for the
compost or soil to be monitored regularly for specific residues."
For my nickel the NRCS 317 standard is too hot, too fast and short on
detail, at least the version that was up at the website:
http://www.ams.usda.gov/nop/nop2000/nop/nrcscompost.html
My concern with the hot composting is that you can get the sterilization
effect followed by pathogen regrowth, for example with manure and animal
mortalities, and someone pushing the envelope with little guidance might
very well do just that.
Forgive me, but I have little confidence in 21 day dead animal
compost.....not to mention manure. The NRCS 317 standard suggests operating
temps between 130 and 170 degrees F. Temps above 155 or so will get you
cooked material. In the words of USDA microbiologist Pat Millner,
" If compost were to be 'cooked' , nutrients wouldn't be stabilized enough
and microbial diversity would be decreased to the point that any subsequent
pathogens that contacted the treated material might re-colonize it. In the
absence of well stabilized compost with a competitive microflora this might
result in a product with a pathogen content nearly as great as the untreated
material."
Farrell discusses this whole temperature and recontamination problem in his
article, "Fecal Pathogen Control During Composting", which is page 282 in
The Science and Engineering of Composting, Hoitink and Keener, eds, 1993,
Renaissance Publications, ISBN 0-936645-15-6. Indeed, the whole thrust of
many articles in this text indicate that high temperature composting (>140
degrees F or 60 degrees C ) is a bane and a curse and a bother. It is also
something very rarely found in nature, I might add.
And, hot compost made in this way would have little in the way of disease
suppressive properties, as I understand it. Additionally, chemical
contaminants like chlordane are less likely to be broken down in a short
thermophilic composting process.
The time frame given is not so realistic, I think. Jim McNelly, a veteran
composter and Vice President of the US Composting Council, sees 105 days as
the best you can do:
>Personally, I believe that the optimum rate of composting is a geometric
>pattern of seven days in the initial "hot" phase, fourteen days in an
>active composting period, twenty-eight days in a mesophilic initial curing
>phase, and then a final fifty-six days of curing. 7+14+28+56 = 105 days.
(----recent email to the Composting Council List)
Compare this to the 21-60 day time frame suggested in NRCS 317.....
Luckily, one has some loopholes....for example uncomposted plant and animal
wastes can be used, and manure if it is 'aged and well-decomposed' need not
be jumped through the hoop of NRCS 317....and should it happen that you age
it and decompose it through the good offices of worms, well I suppose that
shouldn't raise any eyebrows.
(One of the virtues of vermicomposting is that the worms establish a
competitive microflora that does not support pathogen regrowth, a process
known as vermi-stabilization. In fact, worm composting alone has
demonstrated full pathogen control in biosolids composting in one Florida
study:
http://gnv.fdt.net/~windle/refrence/nov99.htm )
So, since this is the first of supposedly many 'practice standards' the USDA
wants to impose on capital-O Organics, and it seems inadequate in so many
ways, maybe the writing is on the wall that whoever is behind all this
either is unable or unwilling to find the sort of broad umbrella approach
with suitable limits that might be acceptable and useful to the entire
organic community. Give them an inch, you know, and away goes the yardstick!
Someone tell me again, why is this an improvement on OCIA and other private
and/or state certification agencies, making their own marketing reputations?
The cure looks worse than the disease, from where I sit.
Organically,
Frank Teuton----resisting the urge to say "These aren't the 'droids you're
looking for...."
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