Subsoil Plow / Keyline Plow Research

[Sullivan]

Hi all,
I’ve just joined the site to share some information I’ve come across. I have been looking into the feasibility of pulling a subsoil plow to penetrate at least a foot, this to somewhat stunt the growth of fruit and nut trees by trimming their root growth closest to the surface or create a trench to direct water flow.
Please note:
-the subsoilers described appear not to be the chisel type we know but rather something like a very thin moldboard
-number of horses needed depends on draft which depends some on depth but also a fair amount on soil type. Some one plowing on sandy loam may get by with a single horse and some one on clay may need three to four times that.

What I have read is the following:

The Book of the Farm (1854): A team of two or three pull a moldboard plow in the desired path of the subsoil plow, this to a depth of approximately 7in. A team of four of five then follow the path with a subsoil plow and plow this furrow an additional 9 inches, leaving a 16 inch furrow.

American Agriculturist (1865): Also encourages a double plowing but adds that a single team or yoke can draw the plow 10 to 14 inches deeper the second time, but from there more inches become rapidly harder. For anything closer to 20 inches, they recommend several teams or yokes.

Mr. Bockoven’s Response (1897): In South Dakota (on what he calls common prairie loam) he found that he was able to subsoil 80 acres with four good horses at a depth of 15 to 18 inches. Trenches and furrows dug 2 feet apart. At this time subsoiling without plowing with a moldboard first was just being developed.
He goes on to say that after subsoiling, he found the ground overall far more workable and halved the horses he needed to dig praties.

Attachments:

You must be logged in to view attached files.

[Crabapple Farm]

I did some “double plowing” years back when at Howell Farm in NJ. We would do a round with the moldboard, then switch to a walking chisel plow run about 6″ deep in the bottom of the furrow. We didn’t chisel every furrow, I think about every three or four – this was for field culture where the whole field was getting plowed. That was a single pair of Devon oxen (~1600# each) in pretty heavy soil. A larger team in lighter soil would be able to go deeper.
My limited experience with a Yeoman’s keyline plow even longer ago than that is that they do indeed pull easier than the chisel and subsoiler designs available in this country. … Market Farm’s website says that they have finally gotten them in. Rigging them to a forecart or walking toolbar would be a project but doable. I would want a spring or something in the attachment if you expect to hit stones at that depth.
The walking toolbar that I used at Howell Farm for the Chisel plow was like I&J’s walking plow/potato plow, where the share could be taken off and replaced with a different bottom.
-Tevis

[Author]

Posts