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RE: [compost_tea] Letter to the Editor



Dear Kevin:

This article points out an issue I brought up a few weeks ago: people 
already have a definition of compost tea and when we try to talk about 
AACT, we've got an uphill battle because we have to reeducate them about 
what AACT is before we can talk about what AACT does.

One problem with this is that people think they know what CT is and we 
think they know what we are talking about when we use the term CT or even 
AACT, so we all think we are on the same page but we are not.  We may not 
realize that reeducation needs to occur.

I happen to agree with Sue that there are two types of CT.  It's not the 
general population's fault if they think CT can be an anaerobic brew. 
 That's our fault.  Practicioners of AACT have borrowed a term that has 
been used for many, many years to mean one thing and redefined it to meet 
our own needs.

I think a rebuttal to the article is in order.  However, my point remains. 
 Practicioners of AACT are going to be waging this war for a LONG time.  It 
would be a lot easier to call our product something people have never heard 
of so we can give a quick definition of it and all be on the same page.

Paulette


-----Original Message-----
From:	kevin john richardon [SMTP:kmagic@backpacker.com]
Sent:	Friday, June 20, 2003 5:23 AM
To:	compost_tea@yahoogroups.com
Subject:	[compost_tea] Letter to the Editor

Hello Friends,

Please take time to consider the following, brief article which appeared 
yesterday, Thursday, June 19, in the Anchorage Daily News:

Quality counts with compost tea


By SUE LINCOLN
Daily News correspondent

(Published: June 19, 2003)
The Cooperative Extension Service horticulture office receives many 
inquiries about compost tea -- how to make it, the benefits and if it 
really works. To answer these questions, one must have some knowledge of 
plant/soil interactions.

Soil is a very complex community consisting of millions of microscopic 
living organisms and decaying organic material. Soil scientists define soil 
as a combination of three particles varying widely in size and chemical 
reactivity: sand, silt and clay, plus organic matter. Plant nutrient 
availability depends on the structure and texture of a soil as well as 
microbial activity. Texture depends on the percentage of sand, silt and 
clay in the soil.

A soil that is high in sand has large particles and large pore spaces where 
water and nutrients can flow through and beyond the reach of the root 
system. Because of the large particles consisting mainly of silicon dioxide 
and the lack of clay particles, chemical ions in soil solution are not 
attracted to the sand particles and tend to move with soil water.

Soils high in silt have smaller particles than sand and smaller pore spaces 
for water and gas exchange. Silty soils tend to release nutrient ions into 
soil solution with time and are often highly productive.

A soil that is high in clay has very small particles and very small pore 
spaces allowing ions to be held tightly to their surface but not allowing 
water and air permeability, resulting in a struggling microbe population 
and poor aeration. Although soils high in clay are considered to have high 
cation-exchange capacity (the chemical reaction in the soil), which is 
desirous for plants, the particles are so small and tightly packed together 
it is difficult for root growth, gas exchange for microbial activity and 
diffusion of nutrients to the root surface.

The addition of organic material such as compost is beneficial to soil 
structure and adds to the total cation-exchange capacity of the soil. The 
added organic material increases moisture retention and helps to increase 
microbial populations. Microbes break down organic particles into chemical 
components usable to plants. This microbial action enables the nutrients to 
be available for plant roots to absorb.

COMPOST and COMPOST TEA

Compost is the result of plant material that has been decomposed by soil 
microbes to a soil-like state -- although it is not soil. In general, the 
benefits of adding compost to soil are many. However, the quality of the 
compost is important. In order to achieve good quality compost, steps must 
be taken to use quality ingredients, maintain temperature and moisture and 
ensure good air circulation throughout the composting process. These steps 
also must be taken for a quality compost tea. The compost tea will only be 
as good as the compost used.

Compost tea is the leachate of compost where water is added to extract 
nutrients and microbes. The tea consists of a very large and diverse 
microbial community. Some recipes include the addition of carbohydrates 
such as yeast, molasses or other sugars to encourage microbe reproduction.

There are basically two types of compost tea: anaerobic and aerobic.

For the anaerobic method, the compost is allowed to sit in water for 
several days. By allowing the water to sit undisturbed, the 
anaerobic-microbe population increases while the microbes that prefer an 
oxygenated environment decline.

In the aerobic method, air is pumped through the solution thereby 
increasing the aerobic-microbe population within the solution. Depending on 
what the compost tea will be used for will determine which method is used.

TWO WAYS TO USE TEA

There are basically two uses for compost tea. One is to increase microbe 
populations in the soil so they can break down and release nutrients to be 
available to plants. The other is a foliar spray used for nutrient 
application as well as a fungicide.

There is quite a controversy over the claimed benefits of compost tea. The 
scientific community is just beginning to conduct controlled studies on how 
the soil community and plants respond to the addition of compost tea. There 
is consensus, though, that compost tea added to the soil does add to the 
microbe population, thus enhancing the probability of increasing soil 
fertility by microbial release of nutrients. However, the use of compost 
tea as a foliar fungicide has brought the largest controversy.

There have been several controlled experimental studies using compost tea 
as a fungicide on specific pathogens and crops. Results have been 
conflicting. However, some results suggest that compost tea brewed using 
the anaerobic method may be more effective as a disease suppressive than 
compost tea brewed using the aerobic method. In other studies, foliar 
application of compost tea encouraged pathogen growth.

USDA CONCERNS

The U.S. Department of Agriculture has documented concern over using 
compost tea as a foliar spray. Pathogens such as E. coli and Samonella have 
been cultured from the tea when carbohydrates were added to the brew. One 
experiment suggested that by not adding the carbohydrates, E. coli could be 
eliminated even though the pathogen was present in the compost prior to 
brewing the tea. In addition to the concern of dangerous pathogens, foliar 
applications of compost tea can be high in salts, which can burn tender 
foliage. This is another case for the use of quality compost materials.

There is also controversy on the use of compost tea in organic farming. 
Because dangerous pathogens reproduce between the temperatures of 40 and 
140 degrees, compost would need to heat to at least 150 degrees to kill all 
the pathogens. Prior to using animal manure, the National Organic Standards 
Board requires the material to be heated in excess of 150 degrees for a 
minimum of one hour and dried to a moisture level of 12 percent or less. 
Unfortunately, if the compost was heated to this high temperature all the 
good microbes would be killed as well. The Agriculture Marketing Service of 
the USDA recommends that if compost tea is used as a foliar spray on edible 
crops, harvest should not take place less than 120 days after application 
unless the compost tea is made without the addition of carbohydrates.

In order to keep healthy while consuming homegrown, organically produced  
 food using compost tea as an amendment, use quality ingredients when 
building the compost heap. When the compost is finished, refrain from 
adding additional carbohydrates to the brew if foliar applications will be 
made.

Sue Lincoln is a horticulture program assistant with the University of 
Alaska Fairbanks Cooperate Extension Service. She is located in the 
Anchorage office. Contact her at 786-6315.

The Anchorage Daily News

Hmmm... I feel compelled to respond to a few items.  Please let me know 
what YOU think.  Promptness will be an issue as I would like to submitt a 
version of the following, Letter to the Editor:

Local Solutions
19025 Villages Scenic Pkwy
Anchorage, Alaska  99516
(907) 522-0679   907) 317-8455

Thursday,  June 19,  2003

Letter to the Editor
Anchorage Daily News

Quali-tea results with Compost Tea

Wow, Sue Lincoln grabbed my attention!

Leading with such a concise yet informed portrayal of soil dynamics, I was 
anxious to read further.  Turning the page, I expected what followed to 
champion the necessity of securing a quality source of compost to brew 
quality compost tea with? I finished the column feeling my understanding of 
Compost Tea conflicted and doubting Ms. Lincoln's compilation of facts.

In all fairness, I assume responsibility for taking the initiative to seek 
out more information to better and verify my own understanding, yet I also 
intend to encourage all of us to be diligent and accountable in the 
reporting of our research and development to productively advance the 
enormous potential of the emerging science of Compost Tea.

Please know Dr. Elaine Ingham and Soil Foodweb Inc., a renowned resource 
recognized as the foremost authority in the field of soil microbiology, is 
adamant that Anaerobic Leachates of Compost ARE NOT Compost Tea.

This may seem like semantics, Sue, yet?

The terminology, "Compost Tea", refers to a watery extract of Compost, made 
by the addition of a determined amount of high quality compost and 
microbial foods to water which IS ALWAYS at least 5.7% Oxygen per Volume! 
 This is important to agree upon.

As a general rule with exceptions, anaerobes produce substances which 
inhibit growth.  We want to provide an environment which promotes the 
growth of aerobic microorganisms.  These are the microbes whose 
interrelationships within their community have the desired, positive, 
beneficial effects on soil and plant characteristics we are attempting to 
cultivate with compost tea.

True Sue, "The compost tea will only be as good as the compost used."  Only 
organisms present in the brewing materials will be found in the Tea.   The 
action alone of adding carbohydrates or any other nutrient will not result 
in the cultivation of pathogens.

I am not aware of Compost Tea having a Salt Index.  As you mention, if 
foliage is being burnt by salts, this also would be a source issue.

Interestingly, Anchorage, Alaska has, to my understanding, one of the three 
known best sources of composted material on the planet.  Certain types of 
Humus, commonly referred to as "peat", posses the finest attributes of a 
composted material.  The most important asset, Sue will agree, is that 
there are NO CONTAMINANTS.  It is virgin material.  Secondly, the number, 
type and diversity of species contained in the Humus is outstanding.  The 
tests register impressive numbers.  This resource is being actively 
conserved by a local group.  Look them up at AlaskaHumus.com.

Facts have been gathered indicating foliar applications of Compost Tea 
achieving 70% leaf coverage or greater successfully suppress disease.  90% 
coverage, 7% of which is of beneficial fungal content, has achieved 100% 
protection!  Yet this accomplishment is not likely achieved by secretions 
of toxins as "-icides" suggest.  Rather the beneficial microbes present in 
Tea out-compete pathogens for space and food resources and in some cases 
predate on disease causing organisms.

Much of the wonderful feedback I receive from those who employ compost tea 
generates a foremost concern for quality.  It is imperative we achieve 
accuracy in the dissemination of information, as public awareness and 
perception of Compost Tea is being developed during this growth stage in 
the industry and we want this science to move forward and realize maximum 
potential.

Please consider these remarks as we gain in our collective knowledge and 
ability to brew and apply Compost Tea.  Thank you for your time and 
consideration.


Best Regards,

Kevin John Richardson


Your input is welcomed.  Especially if I have errored in my facts, 
judgement, etc...

Please feel free to edit.  Suggestions contrary to my current opinion are 
especially warrented.  Please let me know if you think the gal wrote a 
decent peice and I should let it go.  No reason to come off like a jerk, ya 
know?

Peace, Kev
ps sorry soo long

Kevin John Richardson
Local Solutions
19025 Villages Scenic Pkwy
Anchorage, AK 99516
(907) 522 0679 Land
auto forwards to :
(907) 317 8455 Cell
kmagic@backpacker.com




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