"Remember that you are dust, and to dust you shall return". With these words, Episcopalians will receive ash crosses on their foreheads this Wednesday, to mark the beginning of Lent, forty days of penitence and fasting.
It is a particularly favorite worship service for me, in that it recognizes centrally the transitory nature of physical life, yet does so without condemnation or demeaning of that same physical existence. I mention it here as an introduction to talking about that dust from which we all spring, and to which we all return, the soil itself. Soil remains a fundamental aspect of sustainable living, yet it is poorly understood, overlooked, and too often treated "like dirt", a simile whose existence tells you about our cultural values.
Healthy soil isn't dirt. Dirt is an inorganic mishmash of mineral particles. Soil is dirt suffused with organic materials, living things, water, and nutrients. If soil is a lake in the woods, fish leaping from the water and cranes tip-toeing through the lilypads, then dirt is a swimming pool filled with sterile tapwater. We've barely scratched the surface of the ecosystems present in healthy soil, but we've determined a few key points:
(1) Dirt provides nothing more than anchoring for plants; it has to be fed and fertilized constantly for plant growth to occur, as it has negligible "nutritional value". The difference between soil and dirt is the difference between eating vitamin-fortified oatmeal, and eating boiled cardboard.
(2) Dirt is, in effect, immuno-suppressed. Lacking normal soil life, dirt presents no resistance or competition to colonizing pathogens. Therefore, growing in dirt requires constant use of pesticides, fungicides, and insecticides.
(3) Dirt cannot hold water or dissolved nutrients well. Soil holds water and dissolved ions (potassium, nitrates, calcium, etc) exceedingly well, both in the living organisms themselves, and in chemical "traps" like humic acids. Dirt generally holds either no water at all (sandier soils) or forms a nearly-impermeable barrier (clays with no organic matter), neither of which help.
So clearly, we all know to farm on soil, not dirt? Except that isn't what we do. Our current food system depends on artificially-fertilized and propped-up dirt. We actually degrade the soil year after year by planting the same few high-value crops, pillaging the complex nutrient web then trying to "replace" it with massive doses of simple, single-chemical fertilizers. Again, from a human perspective, it's like eating all of the fresh, just-picked apples and pears out of your bowl, then "replacing" them for the next meal with a bowl full of powdered sugar and tap water (since, hey, they are roughly similar chemically speaking, right?)
Historical perspective on soil destruction comes chillingly. Remember the dust bowl of the 30s, with parts of the great plains turning to dead, dusty, crop-killing emptiness? Less than a century previous, the first farmers in the great plains planted in top soil that was six feet deep. Millenia of migrating bison, pooping and grazing and turning up the soil, then migrating away for years before returning, had build an unfathomable store of soil wealth, which we tore through and washed out to sea in three generations. The magnificent cedar forests of Lebanon are mentioned in the Hebrew bible, in the Epic of Gilgamesh, and in ancient accounts of Lebanon as a country of deep green forests, verdant pastures, and rich life. Currently, much of Lebanon is dry scrubland, which happens when you cut down all of the trees. The loss of trees means little holds the soil together. The loss of soil means little can grow back to replenish the soil. And so forth.
What can we do? Lots, actually, remembering that there are regions on Earth where humans have farmed for four thousand years, by maintaining soil health. This is a hugely complex subject, but some key points stand out:
1) Buy sustainably grown food. Get to know your food producers, and don't be afraid to ask questions about how they do what they do. Be an educated consumer - it's your planet, too, and this is stuff you are putting in your body.
2) COMPOST. Start a pile, or contribute to a friend's pile. Every time you remove matter from an area - you harvest fruit, haul away grass clippings, etc - all the stored energy and nutrients leaves the local system. Either the local system just gets weaker and weaker (the dust bowl) or you have to replenish that lost material (compost being the good, soil-building way; massive fertilizer use being the short-term, semi-effective way.) Once you start composting, you'll also be amazed at how much less total trash your household produces.
3) Make choices that build the soil, rather than mining it. Perennial (growing year after year, as opposed to annuals, which grow for one year and die) crops, trees, berry brambles - these send deep, soil-cultivating roots, and sequester more carbon every passing year, and help solidify and strengthen the local microclimate. Look into perennial vegetables like asparagus, taro, Good King Henry, sorrel, artichoke, Jerusalem artichoke, and perennial varieties of kale. If some of these are unfamiliar, don't feel bad - our food system shifted to almost exclusively annual crops in the last century, due in part to the mechanization of farming.
4) Bare soil is dirt in the making. Plant cover crops to hold and build the soil. Make your lawn much lower maintenance by switching to a clover lawn, or a mix of grasses and clovers. This also creates soil-building life, as clover is a nitrogen fixer.
5) Hugelkultur. Aren't you tired of me talking about this yet? If not, start reading here.
6) Biochar. More on this later.
7) Learn that many "annuals" are only annuals because we force them to be. An article on perennial garlic, featuring a man who understands how to stack functions like a master.
An excellent TED talk which covers many of these points.