The book Holistic Management: A New Framework for Decision Making (affiliate link) introduces four key insights that underpin the concept of Holistic Management.
1) The Whole is Greater that the Sum of the Parts
Hence the reason for the word "holistic". Every landscape is part of a broader ecosystem. If we make a small change on our property, say clearing trees or building a dam, it will have an impact on the wider system. Every action we take, we must consider the holistic effect. Later in the book, there is a chapter on forming a holistic goal for your farm, so that you can ensure that everything you do moves you towards the holistic outcome that you want, and doesn't do unexpected damage.
2) Brittle vs Non-brittle Landscapes
Landscapes respond to influences depending on where they sit on a brittleness scale. Non-brittle landscapes have frequent rainfall, a fairly constant growing season and constant decay of biomass. Brittle landscapes, on the other hand, have infrequent rainfall (it can be relatively a lot of rain, but only at certain times of year), a particular/short growing season and decay only occurs when conditions are humid, otherwise biomass tends to oxidise. See more about brittleness here.
I found this concept made sense to me as soon as I heard it. I grew up in a non-brittle landscape (New Zealand), which has rain all year round, and constant decay was obvious to me (i.e. mould in student flats). Coming to Australia I knew that something felt different, but I thought it was just the warmer sub-tropical climate. Actually, the further you go from the coast, the more brittle the landscape becomes. In our current location we get most of our rain in summer, it can be 200-300 mm, but in winter and spring we may get no rain for several weeks. The grass will dry out and go brown or grey (oxidised) and we will find fossilised cow manure completely undecayed. I think when you've experiences both types of landscape first-hand its easy to see the difference.
Brittleness is a very important concept and explains why some farming practices that work in other places are not appropriate here in Australia (later chapters of the book discuss this in more detail). When considering permaculture and farming techniques that I read about, I now ask myself, how brittle is their landscape? Will it work here?
This also explains why its so important for us to hold water in the landscape. As detailed in Peter Andrew's books on Natural Sequence Farming. We get infrequent rain events, so we can't afford to lose the water to run-off.
3) The Predator-Prey Connection
4) Timing is Everything
This relates to the third insight, in that timing of the animals in the landscape is important. The landscape must be exposed to grazing animals for long enough to cause disturbance without damage, and then rested enough to allow recovery, without over-rest.
Allan argues that this is why holistic management is so necessary. It is very difficult to get this timing right without a plan for your entire farming operation. Figuring out your holistic goal is first and then planning grazing, including developing new fencing and watering points to further improve your operation.
Managing grazing is an entire subject on its own. Personally I admire the writings of Throwback at Trapper Creek on the subject of grass and rotational grazing. But I think she is probably in a less brittle landscape (I'm guessing from the green green grass), as is Joel Salatin. I'm not sure I know of any information about rotational grazing in brittle landscapes. This just means extra observation and interaction is required (permaculture principle: observe and interact) to get this right.
What do you think? Are you in a brittle environment? Have you tried mob-stocking or rotational grazing?