Wednesday, January 26, 2005


Dear Reader,

Dumb as Dirt. Dirt-poor. Dirt-cheap. Dirty.

Roget's II: The New Thesaurus, Third Edition, defines "dirt" as:

1. Foul or dirty matter: filth, grime, muck. Slang : crud. See CLEAN.

2. Something that is offensive to accepted standards of decency: bawdry, filth, obscenity, profanity, ribaldry, scatology, smut, vulgarity. Slang : raunch. See DECENT.

Oxford English Dictionary Online doesn't get around to defining dirt as soil until the third definition, preceded by excrement and filth, and followed by foulness, metaphorical foulness, and demeaning phrases.

We despise soil, whether we realize it or not. It is one rung above excrement in our repertory of insults, the baseline of worthlessness.

Yet in the funeral expression "ashes to ashes, dust to dust" survives the ancient recognition of the soil as the source of all life, including our own.

Soil, water, air, and sunlight are the main ingredients seeds need to become the plants that support the animal kingdom. Of these, soil is by far the most complex, the most directly responsible in terms of raw materials for the complexity of plants. Seeds provide the blueprint for the adult plant's complexity, air and water provide most of the bulk elements (carbon, oxygen, hydrogen, and in the case of a few plants nitrogen), and sunlight the energy, but for most plants (those that do not extract nitrogen from the air and fix it in the soil) the crucial ingredient for building proteins (nitrogen) and for all plants the majority of the elements they need (calcium, silicon, selenium, zinc, and so on) come from the dirt and only from the dirt. When we eat plants, we are eating transformed air, water, sunlight, and dirt. Since animals eat plants or other animals, the same is true when we eat animals.

We are what we eat. Whether through our umbilical cords from our mothers' bloodstreams, through our mothers' milk after birth, or more directly as we grow older, we eat transformed dirt, and we could not exist unless we did. We are circulating systems of muddy water, air, and light, and all of these ingredients flow into us from the world around us, through us, and back out into the world. Our dependence on dirt is complete and continuous. There are few things upon which our lives are so completely dependent.

Loath as we are to recognize our dependence on dirt, its value to us, not surprisingly we do not understand it very well. Dirt is extremely complex and varied, and we are still learning embarrassingly basic things about it.

For example, only recently did we learn that the vast network of fungus in forest soil is not a parasite, that it is essential for the forest to survive. Filaments of fungi, called hyphae, are fungi's equivalent to plant roots. They are much finer and more numerous than roots, and are much much more efficient at extracting water and nutrients from the soil. Plants and fungi team up to survive. Fungi send out their hyphae to actually penetrate the cell walls of plant roots, creating a single system of roots and hyphae. The fungi can then share their water and nutrients with the plants, and the plants share their sugars with the fungi. Most plants cannot thrive, or in many cases even survive, without the fungi to help them work the soil. We only figured this out recently.

Forest soil is packed with hyphae, an unbelievably complex network of tiny tubes. A single teaspoon of forest soil contains 100 miles of hyphae. Think about that. Go get yourself a teaspoon of sugar. Look at it. Then think about how far away 100 miles of hyphae can reach from where you are right now. Then pack all that distance into the teaspoon you have in your hand. All that complexity, all that capacity to absorb and transport water and nutrients, is just a fraction of what is in that teaspoonful of forest soil. The visible complexity of a forest exists only because of the invisible complexity in its soil.

Inoculation of seedlings with hyphae to help them grow is becoming part of forestry management, but is not yet a regular part of other forms of agriculture. Introduction of this practice is recent and still ongoing, because until very recently we had no idea plants need fungi to thrive. We spent decades trying to exterminate fungi, dosing crops, forests, and gardens liberally with fungicides, not realizing that a healthy hyphae network also produces its own specialized fungicides to kill off hostile fungi. We still know little about the many varieties of fungi in the world and their hyphae networks, but at least now we have a hint about the complexity of the soils they inhabit and thereby create.

What other rudimentary but essential information do we not yet know about soil? If we are still tripping over things as basic as this, we must assume there is more we do not yet even suspect.

What we do know is that we are running out of soil. Our agricultural, grazing, forestry, mining, landscaping, and sewage management practices have accelerated soil erosion to incredible levels. Our hopes for the future--artificial intelligence, curing cancer and poverty, traveling to the stars--will prove futile mirages if we run out of fertile soil first, which should happen within the next hundred years at this accelerating pace.

Our current, soil-wasteful practices are extremely profitable, so we are unlikely to change anything, except perhaps to begin selling the little remaining soil to each other at obscene prices when it becomes scarce, and then to go to war with each other over fertile land after that. China, which has aggressively adopted American farming practices, is consequently running out of soil faster than any other country. What do you suppose a billion people will do when they cannot feed themselves from their own land?

If this seems pessimistic, if you imagine technology will offer a magic fix to this problem, consider that soil building is a very slow process, taking many centuries to recreate a deep, fertile soil bed. Moving soil from place to place, though difficult and expensive, is doable with current technology, but creating new soil from scratch is another matter. Any soil we did mix up from more primitive materials would be missing the many things we do not yet realize are necessary for sustainable agriculture, the other things besides hyphae that we do not yet understand.

Meanwhile, the agricultural soil we do have is increasingly contaminated by salts and poisons as side effects of how intensively we pump resources (like pesticides and petrochemical fertilizers) into the soil to extract crops from it, and by side effects of industrialization (like perchlorate contamination of California's farmland from the leaky Kerr-McGee rocket-fuel factory in Nevada). The quality of the soil we are losing today is inferior to that of our parents and grandparents.

It would be both ironic and typical of our species if we exterminated ourselves by using up a resource that we held in contempt, used as a metaphor for worthlessness. Dirt is worth more than gold, because gold is optional, and dirt is not.

Where is the dirt going? To the oceans. Erosion by wind and water blow and wash much of it off the land. We extract nutrients from agricultural lands when we harvest and ship away the crops to market. Animals that feed off plants do so locally, and they defecate locally, thereby rebuilding the soil near the plants they feed upon. We, however, dump our sewage into the oceans, creating great rivers of soil nutrients that flow from agricultural lands to the bottom of the oceans, via our bodies.

As far as I know, there is little we can do to reverse the soil erosion that has already occurred. Dredging the oceans is impractical, given the amount of fossil fuels we have left, and would doubtless do incredible damage to ocean ecosystems that are already reeling from our unsustainable harvesting of fish, shellfish, and other ocean resources.

What we could conceivably do, though, is drastically reduce soil erosion. We would need to change our industrial practices. We would also need to eliminate poisons from our diet and environment to make our sewage fit to compost back into soil; that would have the added benefit of making us healthier. We would then need to overhaul our sewage management practices to return it to the agricultural lands as fertilizer. Taken together, these changes would help conserve the soil we have left.

Although we will not survive without these changes, none of it is profitable in a market economy, so we will not do it. There are powerful economic incentives for us to argue that it is too soon to tell whether soil loss is a serious enough problem, right up until it is too late to do anything about it. I am betting we will remain too self-involved and short-sighted to register the meaning of soil loss until most of it is gone. After, all, it is just dirt, right?

If we did, though, if by some miracle we made whatever changes are needed to make it possible for our society to value and act on stopping soil erosion, we could then build up the fertility of the soil we have left. A few older cultures were able to conserve and enrich even the faint scraps of soil on steep mountain slopes, farming the same thin soils successfully for centuries. The organic farming movement has helped us relearn old lessons about soil conservation and development. If we applied those practices, we could survive the loss of soil we have sustained to date, and eventually, over the centuries, we could slowly deepen our fertile soil beds, maybe even back to their pre-industrial levels.

We have already damaged the soil so deeply that we have left what will probably be a permanent record in the Earth's geology to show we were here and what we did. If we keep on as we have, our future is rocky. Literally. If we reverse our wasteful soil practices and spend the next few millennia deepening the soil, that too will be writ in the geological record. As a species, we still have time to leave behind us a life-promoting legacy, but we will have to change profoundly to want to do that. We will have to unite around this common goal as a species for millennia, something we have never done.

If we imagine uniting our species around a shared set of core values, if we imagine ten commandments in a sustainable worldwide culture, one of those ten will have to be something like this:

Protect the soil; it is your food, your body, and mother to us all.

When faced with essential but seemingly impossible tasks, I find wisdom in a bumper sticker, of all things, that I see all over Seattle: "Think globally. Act locally." Or as Gandhi said, we must be the change we want to see in the world. Lead by example. Learn about dirt, and slowly change your life by what you learn.

For my part, I have begun with composting, with building up the soil in my own gardens and yard. I also buy organic farm products whenever I can, because organic practices protect the soil more than conventional farming, and few actions we can take match the political impact of changing to whom we give our money; when we buy groceries we vote with our dollars. With the help of our friend Linda, we have begun growing some of our own fruits, vegetables, and herbs. These small steps are only a start, but they are something, and as I learn more about soil I will make more changes.

Dear Reader, let us aspire to become dirt-rich.

Sincerely yours,

Postscript: I am indebted to my uncle, Don Baldwin, for leading by example, for growing his own fruits and vegetables, for nurturing and improving the soil in his gardens year by year, and for showing me what a real cucumber is supposed to taste like. I had no idea what I was missing. Thank you, Uncle Don.


janXknits said...

My parents have taken to harvesting worms. They took a class and have been hooked on it ever since. The compost that comes from the worms has made huge differences in their flower baskets each year. And what started out a hundred worms has turned into thousands. Good luck, it is my understanding is that it is very slow, but rewarding.

Marge Marshall said...

Rick - you are such an imformative fellow! I too,take dirt for granted. It is almost as though it was a shirt-tail relative we don't like. Calling it soil makes it seem like more of a contributor. I

Marge Marshall said...

My computer has been fighting me again. My comment got printed before I finished. I had just figured out how to make comments after almost giving up. Back to soil -I enjoy your blogs, even the ones I don't quite understand. They make me think, which is hard work. This one about the soil helps me appreciate what "dirt" does for us Marge

Rick Marshall said...

One of the improvements I want to make to my composting this year is to introduce a second stage in which earthworms have a go at the compost after it has more or less broken down into dirt.

I just need to do some research first to determine whether earthworms are truly native to North America, and if not what the consequences are of their introduction.

Anonymous said...

may be of interest to you.

Anonymous said...

David Brin (of Sci-Fi Fame) wrote an interesting essay that has some bearing on this: