Earth Day Lecture 2008
Presented at Colorado State University
And at the University of Colorado at Boulder
By Bill Logan
Text Copyright 2008 by William Bryant Logan
DIRT: THE ECSTATIC SKIN OF THE EARTH
Happy Earth Day.
I know that Earth Day does not actually mean Dirt Day, but I hope in the
next hour to convince you that it wouldn’t be such a bad thing if it did.
The illustration you see is on the title page of the USDA’s 1938 yearbook
Soils and Men. I think this book is one of the great works of literature ever
published by the United States government. In it, along with much fine
science, the authors dare to ask the question, What is the right
relationship between the citizens of a democracy and their soils? I
think this question is as important now as it was then.
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The illustration is so clean and simple. Yet it shows in outline how
we all get here and why we all remain. The air moves, the sun shines, the
rain falls. The rock decays. The water moves down slopes and into every
crack and furrow. Up come the plants, and from them comes all that lives.
Every bit of this happens in and through the dirt. Mircea Eliade, with a
scholar’s love of big words, put it this way: “Soil is the generative matrix
of all terrestrial manifestations of existence.” In other words, Dirt is the
mother of life on earth.
I find that I have to say a word about the word DIRT. Many
scientists object to my using it. They think it a pejorative word. I use it
because I think of it as a living word. When kids go out to play, they don’t
dig in the soil, they dig in the dirt. Dirt comes from the old Norse, dritten,
meaning shit. It takes that warm and wet dritten to awaken the cold of the
mineral world. In one strip of Calvin and Hobbes, Calvin says, “Look, a
trickle of water running through the dirt.” He smiles at Hobbes. “It looks
like our afternoon just got booked solid.”
It’s no accident that kids love to play in the dirt. We and dirt are
kin. In many ways, we belong to one another. Of course, what remains of
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each person on our death ends up a part of the soil. Even if the
crematorium volatilizes the better part of our flesh, it is quite likely that
our aerosols will form the ice cores for some storm, and so we will fall
again as rain.
But while we live, we and dirt share much more than the same
planet. We and dirt are both about the same age. We are both ephemeral,
secondary products of nature. And we are both widespread, prolific,
individual and changeable.
Rock is ancient. Earth is ancient. The sea is ancient. But we and
the soils we live on, are not. Ninety percent of the world’s productive soils
were born in the last 10,000 years. Yes, there are ancient and fossil soils.
Some of them are up to 300 million years old and are the source of coal.
But the soils we depend upon for food are products of the last Ice Age.
The soils of Fort Collins, for example, are born from the remains of a
Pleistocene river.
Likewise, the species Homo sapiens has been around for at least a
few million years, but human beings – the sort with histories, with stories,
with culture, with languages, with settled dwellings – are also products of
the last 10,000 years.
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In fact, the first human civilizations of which we have record – the
Chinese, Indian, Mesopotamian and Egyptian, were founded on fertile
alluvial soils at the edge of rivers. Where the soils were renewed each year
by floods that brought new minerals and nutrients from upstream – the
Yangtse, the Indus, the Nile – the civilizations survived for thousands of
years. In Mesopotamia, where the rivers eroded uplands and where the dry
climate let salts accumulate in the soil, the civilization was violent and
short-lived.
The Egyptians, at least, clearly got the Nile’s point. SHOW PIX
They worshiped the scarab beetle, a polite name for the dung beetle. (One
wonders if the Victorian ladies who wore Tiffany necklaces of scarabs
would have done so had they known of the creature’s habits.) The scarab
lays its eggs in shit, rolls the shit into a neat ball, and buries the whole
mass. New scarabs emerge from the ground. To the Egyptians, the dung
beetle was a symbol of eternal life. And a renewer of the soil.
Like us, soils have a history, a lifetime, an evolution and an old
age. And they are not simply a mixture. Rather, they are something new
made from the raw materials of rocks and of life.
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They are so various and beautiful in themselves that were we to see
what we were walking on, we would constantly stop to admire it. As it is,
we only see soils when the earth has been cut away beside a road or a river
bank. SHOW PIX
Here is a soil I came upon when I drove around a corner in
Western Spain. I was supposed to be looking for storks, but I found this
wonderful red soil, showing deep layers of oxidized iron. The storks had
to wait. There is the parent rock: isotropic and looking comparatively
dead. Atop it is the soil, which has an evolving structure.
Here is a tapestry of other soils. How different they all are! And
these are just soils from the state of Connecticut. SHOW ILLUS OF
VARIETY OF SOIL PROFILES. Soils have personalites. The reds are
well aerated, the grays anaerobic, the mottled soils are sometimes wet and
sometimes dry. There are soils where time has leached most everything
from top horizons, others where the first horizon is black and deep.
What makes the soil a body in nature, a thing in itself, and not just
a kind of rotten rock? One thing is this various and changing structure in
depth. Another is the way the dirt transforms rocks into clay and dead
creatures into humus.
The mineral part of soil is made out of sand, silt and clay. The first
two of these – the sand and the silt – are just the parent rock broken up
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small. They have much more surface area than the rock did, but they still
have the same crystalline structure. They are, as it were Rockettes.
Not so the clays. Under the falling rain, the flowing water, the
freezing and thawing of ice, they not only break into smaller parts. They
re-form into new layered minerals that have tremendous surface area and
often striking organization. SHOW PIX. Some are stacked like hexagonal
plates. Others rise in sinuous sheets and lean against each other like the
flames of a fire. All have tremendously greater surface area than any of
their parent rocks, and all have an electrical hunger for positively charged
atoms. NOTE THE CRYSTAL IN THE MIDST OF THE CLAY For this
reason, clays are the way station for the many plant nutrients that consist
of positively charged atoms or molecules: magnesium, calcium,
ammonium, for example. In their structure and their behavior, the clays
invite the roots of plants. Here’s the main point: Clays are secondary
minerals, new creations in the soil.
Soils also change the dead into humus, another new creation. Plant
roots in the soil eventually decay, along with everything organic that falls
to earth or is buried in the earth – including us and dung beetle’s load –
not to mention the creatures that actually live in the dirt: the several
million per gram of bacteria and fungi, and the million worms, springtails,
and other creatures per acre. At first, they just make a sort of half-formed
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mass, not very different from the originals of which they are made, but
now mixed and darkening.
With time, water and warmth, however, they turn to humus. No
one exactly knows how to characterize humus. Scientists say things like,
“It is imperfectly understood.” There are certain acids in it and certain
sugars. It is very durable compared to raw organic matter. It is may
survive for thousands of years. Like clay, it is extremely attractive to
positively charged nutrient ions. Better than clay, it tends to build the soil
into stable aggregates that leave room for water and for air. Again, it is
not just living things. It is a secondary body created out of the remains and
the leavings of living things.
With clay and humus, dirt is not just another kind of rock. It is a
new body on this earth. It is everywhere, and as often one soils ages,
another is born. I once walked with Hans Jenny by a dog digging in the
dirt. He watched it a moment. Pointing to the pile of earth the dog had
made, he said, “From this moment, that begins to be a new soil.”
Dirt renews itself practically right under our eyes,. Every
year, thousands of tons of dust are blown into the air in West Africa only
to land in Brazil, denuding the Sahel and feeding crucial phosphorus to the
Brazilian rainforest.
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A volcano blew the island of Krakatoa to bits in 1883, covering a
neighboring island with 100 feet of volcanic dust. Thirty-five years later,
there was a new soil on the island almost 14 inches deep.
Not only our bodies but much else of what we make turn back into
soils.. PIX OF KAMANETZ FORTRESS. Here is Hans Jenny’s sketch of
the Dennaya Tower of the Kamenetz Fortress in the Ukraine. It was
abandoned in 1699, and only 230 years later, the top of its walls had
turned into 12 inches of fresh soil.
You can gauge the rate of stone decay in your area by looking in
old graveyards. Find the oldest tombstones you can read and see of what
they are made. A marble stone may be unreadable after a hundred years –
pretty as it must have looked when new – while the date on a slate stone
may be as crisp as on the day it was carved.
Cleopatra’s Needle – an obelisk built by Thutmose III in about
1450 BC and brought from the silt of the Nile where it had been found, to
New York’s Central Park – soon lost its beautiful lines of hieroglyphics.
The rock surface lifted and crumbled as salts in the stone imbibed plentiful
American rainfall and cracked off slabs. Now a bit of ancient Egypt
belongs to a soil in Central Park.
On large scales and small, soils are always in the making. A friend
of mine had his pickup truck parked under the trees at the Cathedral of St.
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John the Divine. He was hurt in a fall and spent the better part of a year
convalescing. Meantime, the truck just sat there.
In the back of the pickup lay a rough pile of pigeon-spattered
sawed logs, along with a generation of fallen leaves, a broken fanbelt,
an empty yellow antifreeze container, numbers of Styrofoam cups, a
boasted stone, a rusting can of Super Stripe traffic paint, a few
discarded service leaflets and menus for Chinese food, a ticket that
read “admit one”, and a vintage book of diocesan records with
advertisements for long-vanished vestment stores and Episcopal
schools, their lettering now half eaten by mold.
Out of these leavings, a forest began to grow. Not on the
ground. Not beside the truck. Right in the back of it. The lobes of
maple leaves were sharpening as their seedlings sprouted, a light and
glossy green. The red-stemmed and three-leaved poison ivy was
showing its amazing skill at growing out of any slightly shady bit of
dead wood. Seeds of albizia had somehow blown from the one little
understory specimen halfway down the street and taken hold in the
back of the truck. Left out in the rain, the diocesan book had a sprout
in it. The tilted coffee cup had filled with leaf compost, dots of pigeon
shit, and wood mold. All of this was happening in New York City fifty
yards from Amsterdam Avenue, where the 18-wheel truck run by.
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Wherever there are decay and repose, there begins to be soils.
It would be hard to imagine a more improbable set of ingredients, but
even a truck can become dirt. Even an old black pickup truck.
As humans, we are not so different from this dirt. Humans and
soils are spread over the whole earth. We are born and live and die in a
short time compared with the vast slow processes of the planet. We exist
in families, groups, societies, but each of us is an individual. We are
secondary products of the earth. Human beings have come to exist on the
surface of the earth, on the basis of the species Homo sapiens. Dirt has
come to exist on the basis of rock and of organic life. Perhaps the old
saying “From dust you come and to dust you will return”is not just a
poetic way of speaking, but a reminder of this kinship
Yet it seems that we have pretty much forgotten our relationship to
soils. For several centuries now, we have increasingly focused on the huge
and the infinitesimal, drawing back from nature as we experience it into a
wilderness of large and small numbers. It is as if we had to hide our
insignificance with outsized thoughts.
We are addicted to extremes. In science, we are fascinated by
black holes and wormholes and a universe that will someday contract back
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to the point from which it exploded, time running backwards the whole
while. In business, we seek larger and combinations of companies, with
larger profits, larger expenditures, larger use of materials, and more and
more employees. In agriculture, we disregard nature, forcing animals into
larger and larger feedlots, chickens into megabarns of cages where they
lay and lay until they blow their egg-laying organs right out there
backsides.
And it is not just the largest numbers that attract us. So do the
smallest. Consider the nanosecond, a billionth of a second. No, consider
the femtosecond, a millionth of a billionth of a second. No, consider the
attosecond, a billionth of a billionth of a second. And please be aware that
someone is trying to measure a trillionth of a billionth of a second. If he
can do it, he believes, he will be able to detect something he calls gravity
waves.
I have no doubt that the mathematics and the reasoning behind
these measurements are elegant and persuasive, though I am likely
incompetent to judge. Likewise, the efficiencies and economies of scale in
large corporations and in large-scale agriculture are impressive. Yet they
seem more and more to draw us into a world that simply won’t work, no
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matter how well it is designed and planned. It smells off – in the case of
the feedlots and the chicken barns, quite literally so.
There is too much mentality in these systems and too little world.
The science reads like science fiction. The corporation unintentionally but
effectively poisons a whole community. The feedlot smells and its
denizens can barely stand on their feet
Pure science, the corporate boardroom, and the huge feedlot are all
mainly hidden from our sight, but we see the evidence of addiction to the
immense and the tiny in our daily lives. For example, in the ruined skyline
of an average American city.
PIX OF EMPIRE STATE PLAZA. This is the Empire State Plaza
in Albany, New York. I have to go to Albany often, but my jaw drops
every time I see this thing. It must have looked so nice in the maquette.
But it is just too damn big and cares too little for anything around it. It
does not know and respond to its city. It seeks rather to dominate it. It
says, “Hey look at me, I’m bigger and more expensive and smoother and
more regular than anything you ever saw, aren’t I? Well, aren’t I?:Huh,
aren’t I?”
It’s even worse to walk on. In summer, you fry. They have tried to
turn the shade trees into architecture too, so they don’t cast much shade.
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The pool is enormous, shallow, and useless. The grand staircases would
have made Mussolini proud. When I took these pictures recently, I
climbed the stairs – they lead to the state library – and peered through a
glass window 35 feet tall.
What do you think was inside? There, in glass cases on pedestals
were beautiful clay jugs made in Albany and western New York during
the 18th and 19th centuries. What a contrast in scale, in means, in attitude,
in everything! Of course, a sign informed me that the door beside me was
closed and that I would have to return to the plaza, descend to street level,
go out around the building onto the street, enter there, and go up five
flights on an elevator, if I wanted to get inside to see the jugs.
I gave up. When I got back to where I’d parked, I looked around
the corner to a street of older houses. There, I saw this little house. PIX OF
HOUSE. It is not the biggest or the fanciest house on the street. But look
at the lovely arborvitae, how they jump up over the roof. Look how they
are placed, with just a bit of asymmetry. (I’ll bet there were more to start
with and that some of them died.) Look at the fresh paint on the house and
on the trim. It is beautiful and it is in scale with us as human beings.
That thinking big can be dangerous – as well as ugly – to soil and
to ourselves was shown not so very long ago in the Great Depression.
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SHOW PIX Of DUST BOWL. Deforestation and large-scale agriculture
combined to move more soil at once than has happened since the Ice Age.
In the wet winter of 1932 in Mississippi’s Yazoo River basin, cultivated
fields lost 34 tons of soil per acre into the stream. A nearby oak forest lost
75 pounds of soil per acre.
Consider again for a moment the nanosecond, the femtosecond, the
attosecond, and their as-yet-unnamed even more diminutive bit of a
second. Not only are they strange in themselves, but they distract from an
obvious question that is always right before our eyes: What is now,?
When does it occur? Or is now in time at all?
To answer these questions, we need to consult not so much the
higher mathematics as the world of our everyday experience. As the
French philosopher Jacques Maritain wrote, the real world is not the world
of objects but the world of subjects. It is the world in which we exist not
as watchers, but as participants.
I want to suggest that this kind of a shift in focus can lead us to
more wonder, to deeper and more useful knowledge, and to fewer horrific,
unintended consequences. And I think that remembering and revitalizing
our kinship with the dirt helps us go in that direction.
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I don’t what to call this way of approach, but I think I can begin to
characterize it. It involves a responsive, intelligent and committed
relationship with things as they are. It looks through now at nature in the
place and time we share.
Is this an objective or a subjective approach? It is objective insofar
as it is careful, experimental and precise. It is subjective insofar as it
recognizes and nurtures a relationship. It is a lot easier to exploit
something when you have converted it into an object, than when it is a
fellow subject to which we listen and respond. It is one thing to know all
there is to know about an object of study and quite another to become
related to it as a fellow creature.
The intelligent farm is one model for this approach. A farmer I
know in Maine started to work to grow organic vegetable about 20 years
ago. The soils had been under seaside pine forest for a generation. The pH
was 3.5. The extension agent prescribed tons of bagged lime. The farmer
was broke and realized he had a whole beach full of sea shells not 500
yards away. He ground them up and mixed them in, over the protest of his
extension agent. Within five years, he had near-neutral, and very
productive soil. The broken shells not only served as a continuing source
of lime, they also improved the soil texture. By rejecting the solution that
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simply went out to buy X tons of lime and by questioning his own
neighborhood, the farmer came up with a response that was better for the
soil and far less wasteful. He became, in the most literal sense,
responsible. A person who can respond.
When we work with the soil, we don’t need to study the hugest or
tiniest or briefest or longest to feel wonder, and to learn and communicate
the truth. We can look at the dirt, that is as recent, as ephemeral, as
secondary as we are. We can look at what is right beneath our feet.
I want to give you three examples of what I mean. The first is
about a compost man, a man I think of as the Johnny Appleseed of
composting. He responds to a problem by asking about a natural process
and learning to enact it.
The second example is an interlude from my own experience,
digging trenches with the sandhogs in Battery Park in New York City. It
shows how a job in which none of us had much interest was transformed
by our interaction with a pair of trees and their roots in the dirt, until we
felt that we knew them intimately.
The third example tells the story of a visit I made with the great
soil scientist Hans Jenny to the Pygmy Forest in Mendocino California. It
shows how a man who had spent his whole life responding to landscapes
and wondering how they came to be, could finally decipher and love a
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mysterious, dessicated forest of misshapen dwarfs. Jenny had an ability I
have never seen so fully formed in anyone else to see and understand what
was before him, and to tell its story without tailoring or fudging the results
to satisfy a system or even our human needs.
Example One.
I met Clark Gregory in 1992. I wish I could show you a picture of him, but
alas I didn’t take one, and now Gregory has died. I had had a compost bin
in my yard since I was a kid, but I wasn’t prepared for anything like Clark
Gregory. We were going to visit compost sites in Florida, alternatives to
the Dump. He was presented with places overwhelmed with what they
were throwing away: forestry scraps, fishing scraps, weeds, farm and
orchard scraps.
Gregory met me at the Orlando Airport, a place that seems to have
been made to resist composting. Everything there is dayglow orange or
tropigreen, and everything is plastic. He sat me next to him in a rental car
and slung a gallon Ziploc bag into my lap. “Smell that,” he said.
It looked dark and it felt squishy. “What is it?” I asked. After all,
I’d just met the guy.
“Scallop viscera compost,” he replied.
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Ah….Well, I was asking for it, so I opened the bag and took a very
slight whiff. Then I breathed in deeply. It smelled sweet and earthy, with a
little tang of citrus somewhere. If I’d been a wine taster, I could probably
have described it fully, but it was more than ok. It was very pleasant.
“Ninety six tons of scallop viscera, twelve hundred yards of
shredded pine bark from a log builder, twenty-four tons of orange
peel, and nine tons of shredded water hyacinth,” said Gregory.
What? I asked.
“That’s what it’s made out of,” he said. “That’s what we’re
going to see.”
Actually, we had several stops. We drove and drove. We drove for
more than an hour through a paper forest of even-age pine trees. Much of
it gets turned into toilet paper. It is a forest on which American wipes its
ass. We visited a huge incinerator that was supposed to turn mixed trash
into fuel and to keep the toxic remnants in special containment units.
When we asked the managers how they really dealt with the concentrated
toxic residue, they mumbled something about underground vaults.
This conversation made me scared and it made Gregory mad.
We were talking about the dangers of the incinerator and the
problems with average waste disposal sites. I was thinking of the heavy
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metals in AA batteries. I asked him, “I know that you can compost many
things, but aren’t there things that just have to be thrown away?”
“There’s no such place as away,” he replied curtly.
“Look,” I insisted. “Compost is compost, but aren’t some things
just waste?
He answered, “It isn’t waste until it’s wasted.” SHOW PIX
I had recently learned something about the truth of this statement
from Gregory’s associate Will Brinton of Wood’s End Laboratory in
Maine. Brinton is a fine compost scientist who has managed the
composting of everything from an entire crop of virus-laden potatoes
SHOW PIX to left-over munitions at the Aberdeen Proving Grounds. Will
had spoken with precision about the right mix for the ingredients and
reaching the right temperature in the pile to kill pathogens without
overheating it. I wondered what would happen if you overheated a
munitions compost!
Gregory and I arrived at the landfill where the scallop viscera was
composting. There were windrows of compost a football field long and 8
feet high, but they were dwarfed by the landfill behind them. Tractors atop
the landfill’s hills looked like toys. The summit of Mount Trash was the
tallest point in Brevard County.
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The landfill’s managers explained what they were doing. Then,
they gave me a ride with the operator, Ollie, on the big machine that
turned the windrows. SHOW PIX OF SCAT AND WINDROW. I asked
Ollie if it smelled.
“Oh, it smells pretty bad for a day,” He said. “Then it smells better
and better. Up there on the hill,” he added, pointing to the immense
mountain of compacted garbage, “it smells bad all the time.”
When we are done with our ride, he fishes around in the windrows.
He finds a seashell and takes a whiff, winces and hands it to me. “Here, “
he said, “This is the worst it can smell.”
It is the olfactory equivalent of being blinded. The smell is beyond
death. It makes my gorge rise.
Ollie knocks the shell out of my hand.
I am now more in awe than I was of that sweet-smelling bag of the
same stuff that Gregory had handed me in his car.
Later that day we visit a small country landfill in the armpit of
Florida near a small town with the improbable name of Panacea. The area
is big on two things: crab fishing and pine plantations, perfect ingredients
for a compost. Sure enough, we go back behind the piles of discarded
water heaters and sofas, and there are three long rows of black compost.
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Steam rises from them. A pine forest stands behind them. It looks like a
Chinese brush painting.
“We’ll just chip away a little at a time,” said Gregory, who was
beginning to recover from his disgust at the incinerator, “and pretty soon
hardly anything will be going to the landfill anymore.”
That evening, we were sitting on folding chairs on the front porch
of the local motel. A man appeared who was one of the county legislators.
We got to talking about compost and about Bush Senior’s recent war in
Iraq. After awhile and a beer, the senator said, “Hell, if we can drop a
bomb down a stovepipe, we ought to be able to deal with our garbage.”
The science – or whatever you want to call it – of Clark Gregory
and Will Brinton is about just that. They learn all they can about the
natural processes of microbial decay in the soil. By enacting the natural
process, they bring balance back to the landscape. And there is something
urgent about the work. As the chief of the Brevard County landfill put it,
“You can’t hide nothing. Your garbage tells on you.”
Example two.
In my work as an arborist, I am sometimes called on to babysit tree
roots. Urban trees often have tiny root systems compared to trees in their
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natural settings, so construction damage – particularly severing even a few
large roots near the trunk – can kill the trees.
I was called to protect two sweetgum trees in Battery Park in New
York City. SHOW PIX That is the park from which boats leave for the
Statue of Liberty. They were putting in a new subway tunnel smack in the
middle of it. A trench five feet deep and six feet wide, meant to carry
electric and other utilities, had to be dug from the street to the tunnel, right
across the park between two large mature trees.
I met a crew of five sandhogs, union guys who dig for a living.
They were puzzled to be meeting an arborist and not altogether happy that
they were going to have to dig these trenches entirely by hand, watching
out for roots with every spade thrust. I was not very interested either. I had
other things to do than to be schoolmarm to a bunch of sandhogs.
Before we began, I showed them the two sweetgums. I pointed to
the root flare – the way that the base of the tree swelled out into the
landscape – and told them where I thought there might be roots.
Why was one tree so much bigger than the other, one of the
sandhogs asked.
What a good question! I hadn’t thought. I could tell the two trees
had been planted at just the same time.
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We looked up. The southernmost of the trees was planted across
from a street that ran straight through to the east side of Manhattan. It got
full morning sun during much of the growing season. The northernmost of
the trees was in the shadow of a tall building. It got no morning sun. The
first of the two was by far the larger tree.
By this time, both the sandhogs and I were much more interested
in the job than we had been. We wanted to know where the roots were and
whether the difference in the tree’s aboveground parts would be reflected
in the roots.
When they hit the first root, the man who scarred it with the point
of his shovel swore. “It’s ok,” I said. “Now let’s dig carefully around it.” I
got out a little Japanese soil knife I use, while they started gently prodding
with the shovel tips to expose the outline of the root. We found that it
ramified inside our trench and that it had both an upper and a lower
branch. When we had it fully exposed, I wrapped it in burlap and
instructed them as to how we would keep it moist. SHOW PIX
They were beginning to get interested. It took four days to open all
the trenches. By the end, they were working like archaeologists, paring
away soil to preserve the roots without blemish or stain. They competed to
be the ones to run for buckets of water to keep the roots moist.
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And we gradually discovered something very interesting. The
taller tree had aggressive roots, or at least its roots had got there first. The
area between the two trees was at least 75% occupied by the bigger tree’s
roots. The smaller’s roots reached out into the same area, but when they
met the bigger’s they turned aside. We saw before our eyes the evidence
of the power of sunlight, how it made the one tree grow so much faster
than other, though all other things were equal.
But there was something else too. The roots of both trees extended
far out into the landscape. More than 30 feet from either trunk, the roots
suddenly dove deep into the soil. Straight down. And lower than the
bottom of our trench.
Why?
We do not know. Was it a privy hole at one time? This is all fill
soil. Where we were standing used to be part of New York Bay. Was it
some wonderful bit of nutritious fill? We do not know. But we wonder.
By the time we were done, two of the sandhogs had asked how you
get to be an arborist, anyway. Out of a job that none of us had wanted to
do, we became a community that included 5 hole diggers, an arborist and
2 sweetgum trees. And three years later, the trees are fine, because we
took the time to preserve their roots.
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[NOTE THE CALVIN AND HOBBES STRIP: THERE’S TREASURE
EVERYWHERE!]
Example three.
When I began writing DIRT, one of the first things I did was call
the Soil Science Society of America. I asked them to send me a
bibliography of the works of the great soil scientist Hans Jenny.
“We haven’t got it, “they told me. “Why don’t you just get it from
Prof. Jenny himself?”
I said, I thought Prof. Jenny was dead. He’d have to be 90, were he
alive.
Yes, he is 90, they said, and here is his office number in Berkeley.
This was one of the great pieces of luck of my life. Before long, I
was driving north from Berkeley with Hans Jenny to Mendocino to visit
the Pygmy Forest, a perfect chronosequence.
Four decades earlier, Jenny had formalized a set of equations to
describe how any soil is formed, matures and dies. It is a phenomenology
of soils. Any soil is determined, he wrote, by five factors: the climate, the
organic matter, the slope, the parent material, and time. All other things
begin equal, what is the effect of time? At the Pygmy Forest, he found out.
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Driving from Berkeley to Mendocino with Jenny was not
uneventful. “Pull off,” he said suddenly. We were doing 65 on an 8-lane
road somewhere in northern Napa.
“Where?” I asked. There was no exit in sight.
“Right here, right here,” he said.
I put on my flashers and dove to the right, slowing quickly.
“Now, “ he said, getting out of the car and leading me back 100
yards, the air around us buffeted by passing trucks. “Why are there oaks
and vineyards here, and why is there digger pine here?”
We were looking at a soil cut on the edge of the road. To the left of
me on the hills above, were a few live oaks and lines of trellised
grapevines winding away over the rolling hills. But just to the right,
although the hills rolled just the same, there were only sparse grasses and
struggling pine trees.
Jenny stooped to the left and picked up a lump of blondish
sandstone the color of dried grass out of the culvert. He stooped to the
right and picked up a handful of small, sharp-edged friable chunks of a
deep-green rock called serpentinite.
“It’s a pretty color,” he said, holding up the green shards, “In fact,
it is the state rock. But it is full of metals that are toxic to most plants.”
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Here was a case where, all other factors being constant, the parent
rock made the difference between rolling hills of oak, grass and vines, and
barren hills of scraggly pine.
I had been passing that landscape all my life, but I had never really
seen it before.
That was easy compared to the Pygmy Forest. Jenny had first been
called there years before to try to explain why in the midst of a beautiful
coastal forest, there was suddenly a soil that grew more lichens than plants
and that flooded with brown water whenever it rained. The plants that did
grow on that flat ground were twisted dwarfs, many of them endemic
subspecies of pines and ericacious plants, varieties found only here.
The pygmies were near the top of a staircase of marine terraces. In
successive steps through the Ice Age and into the Holocene, the
combination of tectonic forces and changing seas levels had thrust up five
different flat terraces out of the Pacific Ocean. As each was formed, the
previous one was lifted higher up the chain
We started with the lowest stair, the one by the sea. It was the kind
of headlands meadow I’d known and loved since I was a child. SHOW
PIX. He pointed to the beach below, where the sea was in the act of
breaking greywacke [GRAWACK] sandstone – the parent material of all
the soils in this area – into smaller pieces suitable for beaches and
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eventually for soils. The headland soil where we stood had a deep loamy
black horizon. It supported a magnificent meadow flora of nodding onion,
wild iris, lupine, bunch grasses, strawberry, yarrow and many more
species.
This was the first, and the youngest, of the terraces that lead up
away from the beach to the pygmy forest, not three miles away.
We drove up to the next terrace. Not only was there no more
meadow, we could not even see back down to the meadow, because we
were deep in a mature forest dominated by majestic redwoods and
Douglas fir, with thick stands of rhododendorns and salal. SHOW PIX
Jenny said that fifty thousand years ago, this forest had itself been a
meadow by the edge of the sea.
On the next terrace up, there was also a lush coastal forest, though
this time dominated by bishop pine. A closer look showed that the plants
were still vigorous here, but there were fewer species and they grew more
sparsely. A gray horizon had formed at the top of this soil. Weathering had
leached most minerals from the surface, leaving only the more resistant
quartz and kaolinite clay. Red iron compounds colored the subsoil, and
some of them had formed hard, rock-like clusters. SHOW PIX
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Jenny prepared me for the next terrace. “It is very different,” he
said simply. We left the car beside a rut on the edge of road and walked in
through a scrubby path of conifers into another world.
The tallest trees there were scarcely taller than a man, and
many rose no higher than our waists, though they were decades or
centuries old. Their trunks were slender as a mummy’s wrists. Here
grew dwarfed, twisted versions of the plants and cypresses on the
lower steps of the staircase. Many were endemic species, found
nowhere else in the world. Almost a quarter of the area was bare
ground or covered with yellow-green lichens. Thirty percent of the
trees were dead or dying. When they perished, they remained
standing, rotting ever so slowly in place. The soil was so acid that few
microorganism could survive it.
There was an 8-foot-deep study trench in the middle of all this, Its
narrow sides sloped so we could enter it. Beneath a slender gray-brown
top layer there was a bone-white horizon at least a foot thick. There were
no free nutrients left in this layer, only the most resistant, insoluble
quartzes. The metallic elements, leached by millennia of rain from that
graying surface now formed not teardrops or even clusters of red-brown
knots, but a solid and unbreakable hardpan horizon, in places more than
three feet thick. To get a piece of it, you had to hit it with a hammer, more
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than once. Only beneath this rocky layer were there any nutrients at all,
and only there did we find any living seedling. Eight feet down came the
parent rock, the greywacke [GRAYWACK] with which the whole thing
had started long ago.
SHOW PIX. The pan is so solid that an average rainfall floods the
land with brown soup whose pH is around 3, about as acid as lemon juice.
What caused this calamity?
Time, nothing but time.
Each of the terraces had been laid down successively. The parent
rock was the same. The climate was the same. The constellation of
possible plants, animals and microbes was the same. The topography was
the same: flat. They differed only in how long they had been exposed to
rain and wind. The youngest was perhaps 5000 years old, the oldest more
than half a million.
Jenny’s was an elegant and beautiful explanation of this landscape
that had puzzled generations of botanists and soil scientists. As we stood
in that trench, our eyes at ground level looking out over the stunted
yellowing landscape, you could smell and taste the truth of it. It was sharp
and sour.
Jenny was silent for a while. At his age, it was an effort for him to
hold his head upright. Then he said, “It’s beautiful, isn’t it.”
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I started. We could not have been looking at the same scene, I
thought. “Your ideas are beautiful,” I told him. “but this landscape is
frightening.”
He did not even turn his head. He just kept looking out over the
lichen-covered ground. “Ah,” he said, “you must look with fox’s eyes.”
What did he mean by that? I have wondered about it ever since. It
now seems to me that Jenny regarded every process as beautiful, once he
had seen into its heart, once he had become related to it.
Jenny succeeded in getting the Pygmy Forest Ecological Staircase
made into a California State Park. I checked a website where state parks
are reviewed by visitors. The Pygmy Forest got pretty low marks. Nothing
special about the meadow or the forest, and all those little dead trees.
Awful! How did that get there?
THAT is the question. And the answer makes a feast for the
understanding.
Jenny more than once asked himself and me the question, “What
does nature have in mind in making soils?” Although he’d spent his life
advising farmers how to improve their husbandry, he was quite sure that
Nature had not made soils only for our benefit.
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I used to badger him to tell me what made a good soil. He usually
refused to answer, but finally he did.
“Good for what?” he asked.
He once described to me the toxic marshes in the San Joaquin
valley, where the trace element selenium had collected in amounts
sufficient to kill migratory birds. Too much irrigation for too long had had
its final resting place in the poorly drained marshes. And so an element
sometimes scarcely detectable in the soil had built up its concentration
until it was dangerous.
I expressed horror and asked what could be done about it. “I
think,” said Jenny, “they should make it into Selenium State Park.”
He was half-kidding but only half. To him, rather than have a
newspaper expose that made a splash for day, it would be better to have a
permanent reminder of the way things go. “If you do this, then that will
happen.”
Late in his long life, Jenny’s colleagues held a birthday dinner for
him, at which they honored his great contributions to soil science. After
they were done, Jenny said how happy he was that they had said all these
things about him while he was still above ground. However, he added, “I
disagree with much that has been said about me.”
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“For all that I think I can say about myself,” he went on, “is that I
have tried to understand nature.”
It may sound like merely an old master’s modesty. That is how I
read it at first. But I believe it is nothing of the sort. It is a very exact
statement.
“You must look with fox’s eyes.”
From the situation you are in to an understanding of its ways.
Responsive, intelligent, committed.
On Earth Day, we could do worse than to dedicate ourselves to
that.
To look with fox’s eyes.
END
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