dps expounded:

Ann wrote:
...My Mantis will go down 11" or so if I work an area thoroughly...


Impressive. At that depth you would have only the top of the engine
sticking above ground level.

There abouts. But the soil is mounded up around, and I move it back
and forth. It's very well worked soil, few rocks, I only do this once
a year, in the spring, to break things up for the season and work in
organic matter. Does the job.
--
Ann, Gardening in zone 6a
Just south of Boston, MA
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