He explained that we are to learn from nature and think of establishing a forest in terms of time, and a series of plantings that come and go until the final forest bio-system matures.
Leave land alone long enough and in many areas it will revert to forest. Damaged land will always start with pioneer plants that will start repairing the land; often these will fix nitrogen. Annual and perenial weeds would cover the earth. Within the protection of these weeds small plants would start to grow: small bushes and shrubs would begin to cover parts of the land and dominate. Finally pioneer trees such as the Acacia (nitrogen-fixing) would start taking hold. Leaf drop and attraction to foraging wildlife would enrich the soil. And so the beginnings of a forest would be born. This succession can take decades but will eventually result in a mature forest.
A forest is self-sustaining; the perennials and annuals are self-seeding and self-sowing. Forest litter deepens over the years to form a wonderful mulch filled with all the micro and macro-organisms needed to bring about sustainability. The soil is undisturbed and life in the soil increases fertility. The bio-diversity of nitrogen-fixing plants, plants that give mulch, plants that attract wildlife and beneficial insects with food, and plants that create habitats, all help develop the forest into a highly beneficial eco-system that in its complex integration is more than the sum of its parts.
We can mimic what we learn in nature and even speed up the process to some degree with more deliberate guidance than nature gives. Digging a swale on contour, to catch rainfall, and then planting it up on the swale mound with nitrogen-fixing plants is a great beginning to our forest. These are relatively short-lived but help condition the soil for those trees and plants we wish to see established. Interspersing these quick-grow plants with valuable and desired young trees to get started will speed up the forest succession process.
He also described how forests are a series of layers. These multiple layers of vegetation maximise health, sustainability and productivity in a forest. Seven distinct layers have been identified. This diagram by Graham Burnett best explains this:
It is also important to understand the structural functioning of a forest. Patterning of plants is not in a neat orchard style but more a clumping together of plants with each part a little different than the next. This has been found to attract more bird-life and greater levels of predatory insect-life than a regulated mono-patterned orchard that has these same seven levels integrated. With a more natural planting there are many more micro-climates created and bio-diversity is in increased. Different plants will be able to take better care of themselves when grown in the little niches created by this mimicry of nature’s forest systems.
Increasingly we are starting to understand more of the soil dynamics that go into increased fertility of the land. Not only above ground, but also below ground, multiple layers of root depths and soil utilization can effect a happy crowding of plants that benefit each other, instead of competeing by contending for the same soil nutrients and requirements. Combining plants in terms of root patterns that are beneficial creates more intensive use of the soil without bringing harm to the plants. A monoculture needs plant spacing for a plant to survive but this is not natural or optimal in terms of plant health and productivity, and all the benefit of land cover, shading, increased moisture, pest protection, and complex soil chemistry is lost.
I have to quote Bill Mollison here; not only because it tickled me to read it, but because his point of view in terms of productivity is accurate:
“We should not confuse order and tidiness. Tidiness is something that happens when you have frontal brain damage. You get very tidy. Tidiness is symptomatic of brain damage. Creativity, on the other hand, is symptomatic of a fairly whole brain, and is usually a disordered affair. The tolerance for disorder is one of the very few healthy signs in life. If you can tolerate disorder you are probably healthy. Creativity is seldom tidy.
Tidiness is like the painting of that straight up and down American with his fork and his straight rows. The British garden is a sign of extraordinary tidiness and functional disorder. You can measure it easily, but it doesn’t yield much. What we want is creative disorder. I repeat, it is not the number of elements in a system that is important, but the degree of functional organization of those elements – beneficial functions.”
A food forest cannot be some regimented plan that totally disregards the value of all nature has to offer in terms of bio-diversity and multiple integrations in complex and varied structures.
I am not aiming to plant a lot of trees and call it a forest, but multiple sets of random ecologies that integrate into a self-sustaining corporate biosystem; a tumbling cascade of colour, texture, highs and lows, with precious “weeds” and other productive plants between, until every part is bursting with life and productivity.
Until next time,
Geoff Lawton’s film “Establishing a Food Forest (the Permaculture Way series)
Bill Mollison: Transcript for a Permaculture Design Course.