The Keyline Plow

The Red Book
& Prices

The RED BOOK is a booklet with pictures illustrating the variety of plows we make and the range of points and components that can go with them.


Deciding Your Plow Configuration

How many horse power per tine (or shank or leg). Whether a three point linkage plow or a trailing model. Size of tines to suit. And other things to ponder and decide on.


Using a Yeomans Plow

When do I first use it. What's a suitable speed. How deep should I go. What points to use. Do I need coulters. And lots of other things it's nice to know.


An Academic’s Keyline Assessment

The late Professor J. MacDonald-Holmes was Dean of the Faculty of Geography, University of Sydney and a truly great Australian. He followed the development of P.A Yeomans' Keyline principles from their inception in the late 1940s.


Creating Fertility. Locating Keylines

Allan Yeomans describes, in basic terms what fertile soil really is and why it is possible and practical to massively enhance the fertility levels of farm soil. Also here, is a description of valley forms and where the Keyline is, and why and how it works. And how to find it.


The Subsoil Plow Story

Keyline cultivation required a plough that didn't turn the soil layers upside down. We looked everywhere. The Texas made Graham-Hoeme Chisel Plow was the only thing we could find available anywhere in the world. We got one and used it, and then made them under license. And sold them here in Australia in the thousands. And that's why I still spell it "plow".


Video Library

A collection of relevant plow and Keyline footage and links to YouTube. Some filmed in the 1950s. Others by Darren Doherty, a long time friend of mine and a Keyline and Permaculture guru.   The Keyline concepts of farm planning, water storage and handling, accelerated soil fertility enhancement and rotational grazing, were developed on our family farms in the early 1950s.   In the 1980s, by combining these experiences with gliding meteorology I conceived the concept of enhancing soil fertility to stop global warming. Allan Yeomans 2016


Yeomans Keyline Systems Explained

The Keyline system has changed only slightly from my father, P.A, Yeomans' original books on Keyline. The main change started in the late 1960s with our work on developing a ripper with almost zero disturbance of soil layer profiles. The modern subsoiler was born and highly accelerated Keyline soil fertility enhancement became possible and practical.


Contacting Us

Yeomans Plow Co Pty Ltd  39 Demand Avenue  Arundel  Gold Coast City  Queensland 4214  Australia


“Carbon Still” Soil Test System

To end Climate Change we pay our farmers $10 a tonne - carbon dioxide equivalent - for increasing the carbon content of their soils.  The best and most consistent measuring process for measuring this carbon increase is by measuring the Loss On Ignition (LOI) of a representative  sample of the soil. Our 'Carbon Still' does the measuring.


Cheap Solar Thermal Electricity

The only significant factors in determining the sale price of the power produced from a solar thermal installation is the cost to cover deprecation and the amount of interest on the money used to build it. That's where our Yeomans system out shines them all.


Pay $10 Trillion to Farmers & Global Warming Ends

Yeomans Protocol & on farm soil carbon test bench



Your guide to navigation around this site. Put the cursor here.

To get back to the top of the site, click the white house on the right.

First; You put the Cursor on one of the 13 numbered buttons.
Second: The button turns yellow and the big square on the left side lights up with a summary of what you will find when you open the page.
Third: Leave the Cursor arrow there and Left Click and you have opened the whole page. The lower part of the screen then comes up with all the information.
Forth:Then scroll up or down to find what you want.
Fifth: Click the WHITE HOUSE if you want to go back up to the top of the page.

3. Using a Yeomans Plow 4. An Academic’s Keyline Assessment 5. Creating Fertility. Locating Keylines 6. The Subsoil Plow Story 7. Video Library 8. Yeomans Keyline Systems Explained 9. Contacting Us

2. Deciding Your Plow Configuration 1. The Red Book
& Prices
13. Your guide to navigation around this site. Put the cursor here.

To get back to the top of the site, click the white house on the right.
10. “Carbon Still” Soil Test System 11. Cheap Solar Thermal Electricity
Pay $10 Trillion to Farmers & Global Warming Ends

Yeomans Protocol & on farm soil carbon test bench


1.  How to decide a plow size ?

Allow 7 to 15 horsepower per tine to determine frame size.

In initial cultivation in very compacted soils – dry hardpans etc. horsepower requirements can initially go up to 20 or even 30 horsepower per tine. So a practical decision on the size of the plow is to allow ten horsepower per tine. So then to start fit only enough tines that are comfortable to pull. And spread them out over the width of the plow. You can also get more tines next season when the soil has developed and the plow is easier to pull.

It’s difficult to imagine how you could make a tine with less resistance going through the ground. That’s why they are made the way they are. And that’s why they generally pull themselves into the ground. So a small plow can often stop a big crawler tractor. But this is not the way to operate. You’re wasting power. The depth wheels, or the crumble roller, must be set to limit this action and make the plow operate at the depth desired.

The root mass moves down progressively each season. If the root mass isn’t interested in going that depth just yet, then it won’t and the cultivation at the extreme depth will close up within a year or so. The depth is determined by the depth of vigorous root activity. Go a few inches below this activity and the roots are happy to move down.

2. Three point linkage, trailing models, which to choose?

The decision is affected by many things, the horsepower of the tractor, what the crops might be, the size of the paddocks, the steepness of the country, the gate sizes on the farms etc.
Below about 150 horse power, tend towards three point linkage.
Row crops, usually 3PL
Small paddocks 3PL. Large paddocks either.
Steep country, tend to 3PL for easier maneuverability.
Crawler tractors, usually trailing models
Irrigation bays 3PL
Trailing model have slightly better pulling angle for penetration at depth.
Trailing models are more expensive.
It’s usually easier to rig an air-seeder to pull behind a trailing model, or to pull a trailing model behind an air seeder.

3. Three Point Linkage Model Depth Control  ? 

It’s good so we patented the system right at the beginning. It won the National Field Days Design award. The editor of “Farm Show” – an American “Choice” type magazine for agricultural machinery and equipment, saw it when in Australia, and wrote it up as one of the three most sensible, and practical, and innovative inventions he’d seen in recent Australian agriculture. .

A main feature adding and contributing to its strength and simplicity of operation occurs because the weight of the plow is shared on both sides with ten separate lugs. Whereas with just about all other systems, the load is taken on one specific point. ( such as a bolt or a pin).The simple steel key that holds and locks it at the chosen depth, always seems to work its way into mesh, never out. And that makes it, safe as houses. To keep it simple there is there is no left or right hand unit. Also the system can be quickly mounted on any front to rear member, and on either side of that member. To top it off I don’t think we’ve ever had a failure, or a jam, anywhere, ever.

With the Yeomans system; in an instant, the whole frame can be set within a couple of inches of the ground or the depth can be set so that the points don’t even touch the ground. Also the cast mounts can be turned upside down for road trailing. Put the steel depth casting on the front and back beams of your plow and you can practically end tow the plow ar highway speeds. You’ll like it.

4. Trailing Model Depth Control ? 

If an accurate constant depth is required, most people fit a set of ram stops on the piston rod. There are two types, the common aluminum clip on and a new one which are twist on split plastic washers. We don’t stock the plastic ones. Generally speaking the plow you will be operating deeper than country is generally worked, generally deeper than is ever worked in your area. At these unexplored depths an inch, more or less makes little difference. The plow uses phasing cylinders so the plow stays even at any depth. Just put it back in about as before and it will be OK. A depth mark somewhere anywhere is all you need.

5.  Yeomans Shank types  

There is a 22 inch shank, fitted to all the GP series. It’s for low horsepower tractors. It takes about three tonnes to sheer pin.

There is a Stump Jump shank for country that is so full of rocks, stones and stumps that it is almost impossible to plow using any type of shank. They trip out at around three tonnes tip load but before they trip they act like a rigid tine and stay in position to considerable depths.

There is a 26 inch shank fitted to all other plows. It takes about six tonnes to shear the sheer pin.

As a general recommendations fit the 26 inch shank plows. They are best in irrigation country especially where hardpans are deep and thick and also where soil leaching is more pronounced. Long shanks are recommended where stubble can occur. 26 inch shanks are best for soils that have the potential for deep cultivation. Also for cultivation where trees are to be planted.

26 inch shanks give more clearance for the attachment of our other equipment. And is the best choice as more depth options are available.

There is also a 31 inch shank a shank with adjustable height. These are for special purposes only.

6. What are the general tine (i.e. shank) spacings ?

Frames are designed for a spacing between tines of , 13” or 1/3 of a metre. Tine spacings can be adjusted to suit what you want to do. What limits your choice is the front to rear beams on the plow frame. Different models and sizes have different locations for these beams. So each specific frame will have a range of even tine spacings that dodge these beams. Generally there is quite a variety of exactly equal tine spacings in every frame and model. Ring the office or email us. We also make three point linkage models as standard for row crops, cotton etc. that permit spacings of 33cm, 50cm and 1 metre, on the one frame.

In pasture work you can pretty much set the spacings at whatever you want At the worst one or two tines will not be at the exact even spacing due to the location of these front to rear beams. That the tines aren’t all exactly even won’t mean a thing in pasture work. As a general guide for pasture set tines or shanks about half a metre to point eight of a metre, say 20” to 32” apart.

For crop work check if the frame that suits you will allows you to set the required spacings. Usually it isn’t a problem. However frames can be ordered to suit any specific spacing. A special frame might cost a little more but usually not much.

Questions used to arise as to the sowing of cereal crops at 12″ or 13″ (one third metres) spacings as opposed to the old established spacings of 6” or 7”. The consensuses in the last several decades has settled down (at least here in Australia) and this is what’s generally been found. Paddocks side by side show no measurable difference in yields between the narrower and wider row spacings. Closer row spacings may be better in dry windy conditions to possibly lower drying effects from the wind. On the other hand with slightly excess moisture, mould and rust problems are more pronounced. It also seems that around 15” (say 375 mm) a yield drop off can occur so that seems to be the safe maximum for cereal crops such as wheat.