Earthworms have a healthy appetite. If you get enough of them
together and don’t disturb them, scientists say they can safely,
quietly dispose of many forms of waste.



Vermiculture is a composting system that uses worms to process
organic waste, said Sid Thompson, a professor of engineering with
the University of Georgia College of Agricultural and
Environmental
Sciences.



The process could be a viable alternative, he said, for current
waste-management practices that continue to grow more expensive
and impractical as the world’s population expands.



Goes in Bad, Comes Out
Good


The earthworms don’t have to be trained for vermiculture
or
do
anything unusual. They just do what comes naturally: eat. As the
worms eat organic materials, such as sludge from wastewater
treatment
plants, they excrete it as castings.


Worm castings, which look much like freeze-dried coffee
crystals,
make good fertilizer for plants. They also improve the water
and nutrient-holding capacity of the soil.

“Castings are more microbially active,” Thompson said.
“The nutrients are more available to plants.”



The worms get rid of the harmful waste and in return provide a
much nicer product that’s not as smelly. Not only are the
castings
easy on the environment, they can catch a good price as well.
Castings are advertised on the Internet for as much as $4.25 per
pound.



Cities around the world are looking to vermiculture to combat
waste problems, Thompson said. Vermiculture in India, one of the
most heavily populated places in the world, gets rid of as much
as 30 tons of waste a day.



Thompson said vermiculture could work for Georgia, too. To be
viable on a large scale, though, it must be proven economically
feasible.



Worms take to sludge like mice to cheese. In fact, one worm can
eat its weight in sludge every day. One pound of worms can eat
and process one pound of sludge.



However, a large land area would be needed for the worms to
process
large amounts of sludge, said Jason Governo, a graduate student
working closely with Thompson’s research.


A Pound of Worms
Can Tell You More


Most vermiculture research uses only one or two worms in
small
laboratory settings. Thompson and Governo are using pounds of
worms in their research.



Their studies show that only 3 to 4 inches of sludge can be
placed
onto the worms at any one time, Governo said. With such a thin
layer, it would take too much land and wouldn’t be economically
feasible for Georgia.



But Thompson said the land problem could be solved simply. He
proposes placing the sludge and the worms in trays and then
stacking
those trays in a tall structure. “There are ways this can
be done for waste in the state,” he said.



Thompson said worms can convert a range of organic material, as
long as the material is presented in an acceptable form.



Georgia is one of the leading poultry producers in the world.
It’s also one of the leading producers of manure from layer hens,
the birds that lay eggs. Large quantities of this manure can
strain
the environment.



Worms, Thompson said, could convert layer manure into a more
environmentally
acceptable product. However, the natural high salt and ammonia
content found in layer manure dries up and kills the worms.



Vermiculture could be the answer to the large volume of chicken
litter produced in Georgia, he said. Scientists just have to find
the right way to present it to the worms.