Hello Owen. I first picked up PA Yoemans seminal book from my local library in my teen years about 45 years ago. It was a well thumbed edition even then. His stuff certainly has staying power and from my multiple attempts to read it in ensuing years, I can say there is a definite need for someone like yourself to break it down and teach the principles in a practical way. I'm sure you have a huge fan club.
I have 200 acres near Grafton NSW Australia with thin stony soil in the hills and alluvial sand country on the river flats. For sure keyline water management principles are applicable EVERYWHERE but my question concerns the value of Keyline PLOUGHING on the sandy soils that are currently the grazing pastures. Your thoughts please.
Thanks for your comments and question... Use of the yeomans sub-soiler/keyline plow can be effective in sandy soils... it is usually recognized to be a bit more effective in tighter soils like clays, but results in sandy soils can also be significant and worthwhile... Also, using this in tandem with good planned grazing approaches just increases the possible benefits.
The basic question to ask with regard to any soil, when considering whether or not to use the sub-soiler, is if the use of this tool will address the weak link or the barrier that is currently preventing soil improvement... This might be a compaction issue for example, which this tool would address very effectively. In dryer parts of the world where water cycles on land have often become ineffective, this is often a tool available that can directly address that issue...
If you already have access to the tool of livestock and can begin to use high densities to obtain more animal impact in the context of holistic planned grazing, this might be an approach that would also lead to effective outcomes (possibly over a little longer time period), but which you could begin right away without having plow/tractor access, etc... On the other hand, if a quick 'jumpstart' is critical, the plow can deliver that.
Hope that gives a sense of some potentials...
Whole Systems Design, Consultation, Education, Group Facilitation