"Alan Sung" wrote:

"ameijers" wrote in message
...
People who clear trees
for a living, when they can get away with it, dozer the root balls and
other
chaff into bigass piles, soak with #2, and burn them. Unless you can leave
them sit till weather washes dirt off, chipper guy won't even want to
touch
them- those dirt clods really cut blade life.

That's not completely true. At a local golf course where they cleared some
woods, all of the stumps were taken out with an excavator and placed in a
huge pile. Then some special piece of machinery was brought in that looked
like a 10 foot diameter cylinder, maybe 8-10 feet high. Inside the cylinder
was a giant flail spinning at a high speed. The giant stumps were dropped in
and what came out of this machine was a nice steady stream of rich looking
soil. I think it was less than 30 seconds to reduce a stump of a 18"
diameter tree to 'nothing'.

Drum grinders. Come in big and bigger sizes. They are what are used for
logging operations, and municipal yard waste recycling.

Amazing what you can find on the 'net, if you do a thorough search for
chipper/shredders. G