Permaculture Designers Manual
CHAPTER 8 – WATER IN PERMACULTURE
Section 8.20 –
Life in Earth in Permaculture
Before we ever learned to cut open the soil, it was thoroughly dug, aerated, and overturned by multitudes of industrious burrowers.
The unploughed meadows of Europe and America are as soft as a great mattress, and are well aerated due to the moles, gophers, worms, prairie dogs, rodents, and larvae eternally at work below ground, even under the snow.
Termites, ants, and crustaceans all do their part. The results are obvious from the good soils and great productivity of unploughed ground which has not been compacted by hooves or machines.
Termites and ants are the earthworms of the deserts and drylands, carrying tons of organic material to underground compost piles, in some of which they may grow fungi to feed their colony.
The upthrown earth, whether from ants or moles, froms a specific niche for annuals to seed on, and wind-blown pioneer trees to occupy.
If birds are the seed scatterers of the forest, burrowers are the gardeners.
Underground and beneficial fungal spores eaten by squirrels or wallaby and activated by their digestive enzymes break hibernation to occupy new ground and help the new roots of acorns and eucalypts to convert soil minerals and liquids to food.
Gophers and moles industriously carry roots and bulbs to secret stores and sometimes forget their hoards, so that sunroot, gladioli, daffodils and hyacinths spring up in unexpected places above ground.
This is how comfrey and sunroot spread, despite their lack of viable seed. They depend not on bees, but on moles and gophers for their increase.
Foxes eat fruits, and defecate on gopher mounds, which are the dug-over areas for new trees.
Wombats may tunnel, overturn, and even topple many hectares of trees, leaving a richly-manured, open, and fertile bed for new forest evolutions.
Rabbits industriously garden thistles, and their tunnels give shelter to possum, squirrels, bandicoots, snakes, and frogs.
Worms and crustaceans, in their damp and sometimes semi-liquid burrows, move up and down like a billion pump plungers, sucking in and expelling air (and thus nitrogen) to roots, and in effect giving the soil its daily breath.
Many creatures mix up special mudbrick soils with body secretions, and from swallows to termites create homes from stabilized soils.
Seeds and spores are burled, excavated, hidden, activated, and forgotten by burrowers, and recycled to life or humus as chance and nature dictate.
Roots die seasonally, invade and retreat, and leave minute or massive tunnels for animals, fungi, and new roots to follow.
I once tried to dig a parsnip out of newly drained swamp ground, following it along an old root trace, but gave up after 2 m.
I did persist in following a 4 cm long engaeid “land crab” or earth lobster to 2 m down and 2 m along, and have often dug out rabbit and mouse burrows to find their nests, mating circuses, air vents, nursing chambers, disposal chutes, and escape hatches.
Many old gopher burrows are filled with plant remains and faecal wastes.
A few dedicated souls in the history of science, from Sir Albert Howard to modern ecologists, try to excavate and discover something of roots, but as a simple bluegum (Eucolyptus globulus) can easily embrace an underground 1.5 ha, a forest is so complex and even intergrafted below ground that the canopy seems simple.
Many desert plants lead a long and sturdy underground life while thin, straggly, and ephemeral in air.
Some insects, like swift moths (Hepialiae) spend 7-8 years underground as large bardi grubs (a succulent treat for Australian diggers), with only a few days of nocturnal foodless lift in air, mating and laying eggs before disappearing again to the root sheaths and soil, as their near cousins the ghost moths and witchetty grubs do in aerial stems.
The bardi grubs, too, open thousands of shafts to the air, and cycle tons of nutrient underground, as do their relatives in air and sunlight.
Their predators follow these hoarders and burrowers below the soil, and hunt them in darkness and secrecy.
The implications for designers are that many of these effects may be put to use, or their uses appreciated; it is as valid to plant an acacia for the considerable by·product of swift moth or ghost moth larvae as it is plant a mulberry for silkworms, and to use moles instead of mole ploughs, or gophers as daffodil gardeners (unpaid ).
Even on shores and the bottom of lakes and seas, the burrowers work to carry nutrients below to roots and to bring up fresh minerals for decomposition, while assisting the flux of liquids and gases across the surfaces of mud media.
Roots have their own PENETRATIONS (depth), PATTERNS or spread, SCHEDULES, seasonal MIGRATIONS to or from the surface, and equivalents of deciduous drop or bark decortication, dying off and sloughing off root branches and bark.
It follows that there is a topography of plants underground that parallels that of plants in air.
There are also basic differences, in that special storages or fire-resistant organs found underground as ligno-tubers, tubers, bulbs, and rhizomes are very common.
Some species secrete phenols or creosoles to inhibit other plants (bracken, tamarisk, Juglandaceae, Brassicas); others encapsulate or surround hapless competitors (Eucolyptus, willows, tamarisks).
Some trap nematodes and other would-be predators, or poison them out (marigolds, fungi, Crolaloria).
While agricultural crops exploit from 0.6-4 m (2-12 feet) below the earth, some trees may penetrate to 50 m (164 feet) in deep desert sands. Around the roots of dune trees, calcium and other minerals are deposited as stone-like secretions by root-associated fungi and bacteria.
Root space sharing is also scheduled, so that spring bulbs have fed, flowered, and died before the tree roots begin their upward thrust for nutrients and water. Tap-rooted late starters such as thistles and comfrey reach deep for late summer moisture, while a very few plants and fungi take advantage of the autumn rains for flowering and dispersal.
Where there is no season of cold death, as in the low latitudes, aerial roots may develop, or strangler figs send down roots from high in the crotches of other trees to the earth, there to build great buttresses as they strangle their host tree in a root well.
For designers, the diversity of roots in soil can be used as effectively as the diversity of crowns and canopies.
Unstable slopes are pegged with the great root “tree nails”, or chestnut and pine, oak and walnut.
Even after a hundred years, the steep slopes of this island (Tasmania) are only just starting to collapse as the roots of the cleared forests rot, and could still be saved by pines, Acacias, or chestnuts.
Bamboo not only holds landslides, but for light structures provides an earthquake-proof mattress of roots.
The root mats of swamp vegetation save bulldozers from watery graves, and the fibrous web of the prairie defeats the wind .
GEOLOGY AND LIFE FORMS
Many rocks and strata on earth arise from the actions of living organisms.
Whether it is the nodules of manganese in oceanic depths, deposits of diatomaceous earth, coal, or limestone, or opals and amber, all once were the products of living organisms.
Much of the strata we see, except much-changed granitic and volcanic deposits, were formed from or modified by life. All soils are life-created, as are the corals and coral sands of many oceanic islands.
Life is also busy transporting and overturning the soils of earth, the stones, and the minerals.
The miles-Iong drifts of sea kelp that float along our coasts may carry hundreds of tons of volcanic boulders held in their roots. I have followed these streams of life over 300 km, and seen them strand on granite beaches, throwing their boulders up on a 9,000 year old pile of basalt, all the hundreds of tons of which were carried there by kelp.
Round stones are dredged from great depths in the mid-Atlantic; this does not mean that they were formed there, but more likely that drift kelp carried them there in their roots.
Before they fly to Japan and Alaska, some millions of petrels (Puffinus tenuirostris) annually fill their crop with Tasmanian pebbles, seeds, and charcoal, which will be voided somewhere in the Pacific.
Life moderates every erosion process, every river basin, every cliff and rock fall. It shapes and reshapes earth in a thousand ways.
The hydraulic weight of great forests, such as were on in the Americas, would have exceeded any water catchment weight we can now afford to build, and dispersed it over a greater area.
This greatly moderates climate, and with it geological processes.
It is possible, in Iran, Greece, North Africa, USA, Mexico, Pakistan, and Australia to see how, in our short history of life destruction, we have brought the hard bones of the earth to the surface by stripping the life skin from it for ephemeral uses.
We can, If we persist, create a moon landscape of the earth. So poor goatherds wander where the lake-forests stood and the forest deities were worshipped.
The religions of resignation and fanaticism follow those of the nature gods, and man-built temples replace trees and tree spirits.