Trees
It’s autumn when everyone celebrates the glorious colours of the trees as they turn — “tree” is one of the first words of many children. A tree is one of those taken-for-granted things, beings, that we suppose we don’t need to understand in more depth. But if we look at what we think trees are and what they have to teach us if we watched and listened properly, they are truly wonderful.
What we call a tree can be part of a much larger and older organism. An aspen can be part of an organism with 10,000 other aspens and that organism can be 10,000 years old — one of the oldest beings on the planet. Notice how the language does us a disservice here: we can only talk of aspen trees as though they were singular, not part of a greater plural.
What we call a tree is almost always part of a family of trees of different species that communicate with each other and help each other out with nutrients and the like. When an old tree dies, it bequeaths its store of food and nutrient to many of its neighbours, often favouring its offspring. The connections in this signalling and sharing are largely fungal, so the notion of species and the spurious “Darwinist” competition is really quite difficult to bring into focus.
Nor is this an effect that takes place over the centuries that trees can live. There is a wonderful experiment with little groups of trees planted in a remote place in Canada. A tree within a group is hooded with a bag that is then filled with carbon dioxide labelled with C14. A Geiger counter is used to detect the presence of carbon from that first tree in other trees in the group. For that to happen, the carbon has to be photosynthesised, then the sugars that have been made have to pass through roots and mycorrhizal fungi into the roots of a second tree and thence into the foliage. That whole process takes less than an hour! This is a living breathing multispecies organism, yet we still think of planting “a tree”.
The flip side of this creative life is that if we plant vast area of a single species like conifer, all we do is kill the soil. One of my favourite books, Seeing like a State, uses the destruction of forests by planting as a metaphor for everything we do wrong.
Water
In the film of the life of Salgardo, the pre-eminent photographer, his father cuts the timber on their farm in Brazil to pay for his children’s education. The farm dries out and becomes arid, streams dry up and the abundance of the place withers. In Salgardo’s later years, with one of his sisters, they successfully reverse the process. They raise from seed thousands of native trees and replant the farm. Lo and behold, as the trees grow the streams start flowing again. The place becomes shady and fertile and beautiful again.
We recently felled a large ash tree that has ash dieback disease. In the middle of the trunk just above root level was a large cavity that, when sawn through, gushed water. People know that trees bring up water from the deeper levels of soil and rock, but I had no idea that the process could be that literal. Last winter, we planted the fields here with hundreds of native trees, most of which died in the summer drought. The ones that all succeeded are in an area partly shaded by some large mature trees. No matter what sort of narrative you build around that, the mature trees produce an environment that allows young trees to flourish. I would expect levels and levels of complexity in what that might mean in terms of mechanism.
Notice that to a gardener, the default narrative is one of planting a tree away from other trees so that it is not having to compete for light and nutrients, the opposite of what we find on the ground. In a farming landscape, trees are in lines along hedgerows, limiting their interaction both with each other and with pasture and crops.
Water doesn’t come on its own, it brings minerals from where it came from. When surface levels of soil are depleted from grazing, from crops, from use of fertiliser or whatever, then the best source of minerals is deeper levels of soil and rock. (Fungi can actually mine the rock for minerals with special hyphae.) When a tree brings up water it creates a more mineralised environment. Farmers are starting to understand that if they have a copse of trees, animals will graze there preferentially to get the minerals they need. But in the rural grant system, pasture is pasture and woodland is woodland and never the two shall meet!
Actually, the process is more active and selective than that, and the fungi bring the minerals that plants need in exchange for sugar from the plants. A tree is a giant machine for conditioning the soil, the plants, the animals, and even the microclimate. Why would you not have trees dotted around in pasture, getting it all to happen? Spoiler: mechanisation, part of why we need these mechanisms anyway.
Trees appear to be in splendid isolation. They are not. They are a very visible part of an ecosystem that they nourish and which nourishes them. Moving mature trees is a difficult process and mostly fails. They are tightly integrated into many processes and those processes include other trees. The isolated tree is a cultural illusion we cherish, nothing more.
Climate
Trees transpire lots of water. An oak for example can transpire 50 gallons a day. That evaporation cannot help but have a cooling effect. Walter Jehne says that it is six degrees cooler under the Canberra trees than in the surrounding areas. And trees have always been planted to make windbreaks, reducing the chill factor when it is cold. In cold climates farmers grow “green barns”, stand of trees where cattle can shelter so they can stay outside all winter.
The worst environments for generating local warming are built environments. There are people who know how and where to plant trees to mitigate that local climate effect. Provisions could easily go into planning permissions, but they won’t. They won’t because it would be an admission that a new shopping mall is affecting the air temperature a hundred miles away.
Tree-cycling
What happens when trees die? They get recycled of course. The trunks and branches sooner of later fall to the floor where instantly they begin to decompose. A huge variety of organisms turn the wood into a rotting feast. Although this process begins instantly, in Overstory by Richard Waters, he has a character studying this recycling process and understanding that for a big redwood on the west coast the processes take a thousand years.[1] We don’t even have the capacity to study such a process as it cycles because of the sheer timescale. We can’t wait around for the huge overlapping succession of organisms to march through.
What we do know is that our common or garden apple trees, for instance, are floor feeders. They send feeder roots up from their main roots to find the nutrients they need in the decomposing material of the forest floor. Now think what it looks like under most apple trees, be they garden or orchard. They are clean, especially of wood with fungal growth. Aesthetic. Hygienic. Typically grass or a circle of bare soil. Supposedly for the benefit of the tree, but actually depriving the tree of what it needs. That is the depth of our ignorance as to what a tree is, and how a forest soil ecosystem works.
We are currently felling a few diseased trees and turning the brash into hardwood chips. The chips will be spread underneath our new fruit trees as a mulch and as a source of food via the colonising fungi. We are simulating a forest floor environment to keep them healthy. I think this is a typical holistic farming move, to accelerate a natural approach to recycling processes.
Trees produce the environment for future trees. The undisturbed recycling of material builds a soil. The forest fires recently expose another facet of this. President (for now) Trump in his allseeingness, tells Californians to clean up the forest floor to prevent fires. That has a tendency to mean spraying glyphosate to kill the underbrush, and other measures that kill the soil. A living soil holds far more water than a dead soil, and the effect of a living soil is to damp down forest fires. Not to prevent them, but to limit their ability to become uncontrollable.
Of course, in the heat of the moment (sorry) people lose their ability to even notice this effect, and their actions to prevent further fires can easily be catastrophically counter-productive. It is highly unlikely that technology has an answer to these problems. The recycling of trees would not be a stable environment if fires were not controlled enough by natural processes.
Tree philosophy
Trees are not what we think they are in predictable ways. We think they are things, individual things, and that is a thinking mistake we make over and over. It comes from wanting to put things in boxes and control them. I watch numbers that are constantly revised and always in the same direction.[2] The date of evidence of human habitation in North America just goes back and back: I saw 130,000 years the other day. That tells me that the reason the first dates were so wrong is because they were badly motivated, that the philosophy of their provenance was wrong. And that they must have suited establishment narratives.
The people who first recognised that trees communicate with each other were vilified. It is now recognised that trees have different channels or mechanisms of communication and it is a safe bet that they have more ways and more purposes than we currently recognise. For instance, the acacia trees in southern Africa which send airborne chemical signals to other nearby acacias when they are being overgrazed. They can increase the tannins in their leaves to make themselves less palatable and less digestible.
We think we can do as we will with trees. We certainly cut them down at a frightening rate and turn them into consumer trash. Tyson Yunkaporta could, if he did not think you were a lost cause, spend weeks and months showing you all the ways in which that is a really stupid thing to do, and all the grotesque knock costs of doing so. If we had that thousand-year patience to observe and understand what trees can teach us about living we would be better, saner, wiser people.
We started by saying how taken for granted trees are. That is a signal that trees have a role in our culture that we have become blind to, probably at immense cost. By splitting a few logs for the woodburner here, I have discovered in a suitably tactile way lots about different wood and different trees. One log split so violently I am left with a dent in my leg, despite the previous log being scarcely marked, from which the axe bounced back. That is what I call education.
The forest schools of Scandinavia are rightly famous, and somewhat copied here in the UK. Most of the school day is spent outside in a forest environment. There is a de-emphasis on formal “education” and curriculum. Children are trusted to climb and to use knives, for instance, without close supervision. The result is children with an inner confidence and competence that takes them far. The trees play a role in this development: we need trees. The Japanese access this later in life as “forest bathing”. A little less confidence in our independence from our environment and our ability to make choices without taking it into account would allow trees to play a proper role in developing wisdom.
[1] I think we wrote previously about the bounty of ‘whale fall’, where a carcass that sinks can support complex undersea eco-systems for decades.
[2] Not unlike Facebook’s privacy breaches and the number of users reportedly affected.
