On 11/17/2014 4:45 PM, Bob Engelhardt wrote:
On 11/17/2014 2:21 PM, dpb wrote:
The origin of the species...

http://www.asabe.org/awards-landmarks/asabe-historic-landmarks/graham-hoeme-chisel-plow-38.aspx

...

I followed that a bit & came to wiki. One thing that it said was that
chisel plows require 10 - 15 hp PER shank/chisel! (Because they go so
deep - 8-10".)

That's possible in hard ground; pretty high for sandy ground out here.
I'd guess w/ chisel points (not sweeps or wide turning shears) 7-10 more
like it for those early versions like the picture.

We pulled a 10-ft with two extensions with an old Farmall 400 that was
about 55 belt HP. It new it was on something but could do it...

Go to heavy clay or the like and all bets are off, however...

I hadn't watched the video there before; I know exactly where the place
showing the man/boy is; it's less than 75 mi from us. Seen quite a few
of the others but don't know precisely where they are/were. Doesn't
(fortunately) bear any resemblance to that now even though we're in
another severe drought that rivals the 30s. We had our lowest recorded
here at the house since granddad homesteaded here last year including
the 30s and 50s of under 7". This year is still way under normal but
we've had a little over 10". Around us within as close as 30 miles
they've had as much a 25"; in September had a single rain within 15
miles that gave them 3 to 6" while we got 0.80".

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