Steve Diver steved@ncatark.uark.edu
Mon Feb 12 13:30:22 2001

Eric Lancaster wrote:

> Does anyone have experience with using EM(Effective Microorganisms) in
> their composting facilities?

EM is a mixed culture of beneficial microorganisms (photosynthetic
bacteria, lactic acid bacteria, yeast, actinomycetes, fermenting
fungi) used as a microbial inoculant to facilitate microbial
remediation of organic wastes.  

I follow EM and I like what it has to offer organic waste
management handling.   But I am still more partial to regular
aerobic thermophyllic composting for large-scale farms
and municipal operations.   

Essentially, when you have poop or food wastes lying around 
exposed to the environment for several days, it will start to go 
putrefactive anaerobic unless you mix it in with carbon materials 
typical of aerobic composting.  Or, you can add EM and 
start a microbial remediation process.

Where you have manures or food wastes, this is where EM can
be very useful.  You can treat these materials at the source,
and keep them from going putrefactive.  

Organic wastes are generated in livestock barns, confinement animal 
operations, restaurants, etc.  EM works with organic amendments,
so this is where EM can be helpful.  Wastewaters from industrial
pollution and sewage and lagoons are other places EM is being used.
There are several livestock lagoons and municipal wastewater 
facilities using EM in California and Missouri. 

EM has been used to clean totally contaminated waters 
surrouding islands in Japan, a bioremediation process done
by introducing EM at the source... where polluted waters
originate as industrial wastewater. 

EM works with organic amendments. From the EM point of view, 
a hog lagoon or a litter-based poultry house is an in-situ microbial 
transformation factory for the production of biofertilizer waiting to 

There are two ways you can think about EM compost. 

First there is bokashi kitchen food waste.  This is done by adding 
pre-inoculated wheat bran (bokashi) into buckets of kitchen food 
scraps.  Air is excluded, because it is a fermentative anaerobic 
process.  Liquid extract is drawn from the bottom of the bucket as 
is accumulates, and the liquid can be poured down the drain to 
bioremediate your pipes and sewage system.  

When your bucket is full, you can pack it into a larger container
and let it sit for a few weeks and allow fermentative to occur.  Then 
you incorporate this biofertilizer into the soil as an organic  
fertilizer.  I've worked with bokashi and seen this finished product;
the transformed organic wastes and odor remediation is impressive.

I like to think of EM-bokashi compost as pickle compost, because it is
a fermentative anaerobic process similar to ensilage and Oriential
foods like kimchi and miso. 

The second way to make compost, is to accumulate massive
quantities of all this bokashi-treated food scraps and build
a large thermophyllic compost pile.  This is being done on a 
massive scale in Korea and Japan.  Over a million households
participate in apartment building pickups of EM-treated kitchen
food scraps, with the material going to farms where it is composted
on a large scale.  

At the University of Missouri in Columbia, there is a dormitory 
pulping food scraps where they are treated with EM and held in 
55-gallon barrels. Then these barrels are taken to a compost site.  
The compost generated is being used in field research for organic 
vegetable production.  The Department of Horticulture has a 
couple of graduate students involved with this research.

Since EM works on the principle or fermentative anaerobic, oxygen is 
exluded.  Therefore, it was explained that the EM compost piles are 
covered with a blue tarp, to exclude oxygen.  The pile does heat up 
-- though I'm not sure to what temperatures.  And apparently, you 
"skim off" finished compost from the outside of the pile.  

In Switzerland, we saw EM being used to treat commercial
salad mix food scraps.  The scrap lettuces and cabbages and
other materials would sit outside in a big heap for 2-3 weeks,
maintained in a fresh condition (a pickled condition) instead
of going putrefacting anaerobic and turning into a black, slimy
mess.  This large facility ran an aerobic compost windrow
sytem (Controlled Microbial Compost) using windrow turners.
So when it was time to build a windrow, the EM-treated 
food scraps were added to the compost windrow as a regular
green chop item, along with all the carbon feedstock and regular
compost feedstock materials.   Thus, EM can be integrated with 
regular aerobic windrow composting.  

My web article on EM, with an extensive list of resources, can 
be found at: 

Nature Farming and Effective Microorganisms

To see a comparison of Aerobic vs EM compost inoculant
starters and processes, see Bob Baars website at Compara.nl:

The Difference between CMC-Starter and SESO / EM

Compara.nl Web Page 

Hope this is helpful,
Steve Diver