Cool soil for carbon sequestration

Hundreds of people must have told me, out of shame and self-loathing, how abysmally they have failed at gardening. Then they proceed to tell me all about the “weed and feed” and other toxic chemicals they apply to their lawns – struggling to keep their yards “green.” They dread the hours spent mowing, watering, raking, and generally toiling thanklessly in the yard. They mow, edge, blow, and bag, yet the result looks sterile and uninteresting. It makes a horrendous noise and smells bad too. I must wonder why they do it. For the most part, lawn and garden industry advertising teaches us to maintain an artificial landscape that destroys nature rather than nurturing and enjoying nature. How else could they make money?

Most people’s eyes glaze over when confronted with the topic of soil science. They have no idea what a central role it plays in our food supply, energy economics, and maintaining a healthy planet. These things affect us all, whether or not we pay attention.

Everyone should experience the process of transforming unproductive hardpan soil into biologically-active, humus-filled loam. Add organic matter and let nature run its course. A bag of bark mulch dumped on a threadbare lawn works well for the sake of demonstration. Fungi, bacteria, protozoans, and arthropods feed and multiply. They aerate the soil as they decompose and mix the organic matter with the underlying inorganic minerals contained in sand, clay, and rock. Eventually, sometimes in 6-12 months, the pile becomes rich, loose, and capable of absorbing sufficient water and air to make it hospitable to a wide variety of garden plants. (See: compost article from University of Maryland, Cooperative Extension Service: “Soil Organic Matter”)

Typical suburban turf maintenance transforms soil into lifeless hardpan, incapable of growing anything but opportunistic wasteland weeds without continual infusions of fertilizers. Ironically, these weeds, if left alone, would eventually die and their organic matter would enrich the soil thereby making it more suitable for other plants. The practice of killing “weeds,” raking and bagging autumn leaves and grass clippings effectively mines organic matter from the soil; thereby keeping it continually at the primary stage of soil formation. These practices reduce soil volume in at least three ways. Organic matter by itself contributes to soil volume. Ants, bugs, worms, and microorganisms aerate the soil as they tunnel through it. This natural aeration process regulates soil moisture, balancing drainage with water retention to keep the soil hospitable for desirable plant growth. (cf: Sustainable Agriculture, University of California, Davis, E.A. Curl) Mining the organic matter – by interrupting the return of dead plant material – starves the soil micro-fauna that make the organic material available to plants while collapsing the tiny air spaces and destroying natural moisture regulation mechanisms. The subsequently compacted soil contains less root mass and fungal mycelia (the mostly white thread-like structures from which mushrooms arise as the fruiting structures). Plant roots and fungal mycelia form the re-bar and glue that gives healthy soil its cohesiveness. Without this cohesive structure, the soil easily erodes.

Making matters worse, suburban turf maintenance typically involves powerful equipment that blows and gouges soil as a side effect of mowing and edging. In countless subdivisions, closely sheared lawns alternate with smooth concrete driveways and walkways that result in a bland, sterile panorama. When autumn wind blows the fallen leaves, they quickly evacuate the vicinity because no hedge or shrub border detains them. My mixed borders of shrubberies and perennial flowers capture leaves blown from several blocks away. Conveniently, this effectively saves me from the expense and hassle of purchasing and spreading beneficial mulch in my flower beds.

Americans cause the erosion of productive topsoil at a rate 17 times faster than it forms (International Union of Geological Sciences, Soil and Sediment Erosion). Nations on other continents using motorized plows and cultivation equipment fare no better. This spells exceedingly bad news for global food production (Plan B, Soil Erosion). It also bodes ill for carbon sequestration. (Ohio State University Extension, Food, Agricultural and Biological Engineering, produced a fact sheet on Soil Carbon Sequestration.) Innovative cultivation practices can not only sequester carbon in the soil and keep it out of the air, but they can also improve the productivity and profitability of farmland.

Perhaps no authoritative institution has taken a stab at calculating how much energy we squander to maintain golf course-like lawns across America. The US Department of Agriculture gives some suggestions about Eco-friendly Landscaping Alternatives. I could not find an estimate of barrel of oil equivalents (BOE) we exhaust on turf scalping. Nevertheless, one could make a few educated guesses. Assume at least a gallon of gasoline to mow an acre of lawn. Take some wild guesses about how many acres or hectares of lawn we maintain in the U.S. We probably burn through a few million barrels per week on this anachronistic fashion craze. I suppose the lawn and garden industry wants us to continue and will do whatever it takes to discourage us from contemplating the pitfalls.

If suburbanites realized the consequences of millions of acres of mowed lawns in terms of energy wasted, dollars exported to OPEC nations, greenhouse gases emitted, urban heat island effect exacerbated (lawns do cool better than pavement, but trees cool way better than lawns), they might think twice about manicuring the lawn. They might actually plant trees, shrubberies, flower beds, wildflower meadows, and other landscape features that don’t require power tools or extensive irrigation for weekly maintenance. They might consider landscape styles that provide food and shelter to birds and other wildlife. They might realize that they can offset their own carbon footprint (Carbon Fund) right at home.

Earth-friendly landscapes don’t need to look like neglected weed lots. Xeriscapes don’t have to look like zero-scapes. If you notice that the curb in front of your house stands taller than the soil in which your lawn grows, you have probably already achieved a zero-scape. You and the previous occupants of your property have successfully compacted and eroded the soil by systematically mining the organic matter out of it. You can easily reverse this losing proposition by returning organic matter to the soil in the form of mulch. Pay attention to everything you do that might erode or compact the soil and do whatever it takes to reverse that destructive process. The improved soil quality will support more plants and a greater variety. The plants and the soil will absorb more carbon from the air. The increased vegetation will decrease the heating load on you and your air conditioner. Your “yard” can become a “garden” and, rather than a source of onerous chores, a place of respite.

The Ladybird Johnson Wildflower Center provides a wealth of advice for those seeking to make their landscapes more ecologically responsible.

Sphere: Related Content

Public health, energy waste, pollution, and landscape power tools

I just wrote to my State Representative, Valinda Bolton. I welcome anyone who feels similarly indignant to echo these sentiments to their elected officials.

Please consider these affected constituencies: allergy sufferers, asthmatics, people sensitive to dust in their eyes, noses or throats, people who enjoy live plants and trees in the landscape, people stressed by loud and persistent noise, people concerned about ground-level ozone pollution damaging their lungs, people concerned about wasteful use of petroleum products.

The problem: Twice a week, contract workers visit the TXDoT building on 11th St @ Brazos with noisy machines that propel dust, debris, and noxious fumes into our air, streets, neighboring properties, eyes, noses, and throats. Every day, these ill-conceived machines create a nuisance all over Austin and elsewhere. The highly inefficient gasoline-powered engines -- even when new -- create noise, vibration, and fumes that cause health problems for the people hired to use them as well as people who live, work, or visit anywhere near where these machines do their dirty work. Supposedly, these power tools save time. I contend that they merely transfer debris from one property to adjoining properties and into the public space while creating an entirely new set of problems themselves. Austin suffers enough from airborne allergens, such as what causes "cedar fever." We don't need to actively contribute to respiratory ailments with landscape maintenance practices. In addition to pollution and health problems, these machines waste valuable fuel and accelerate the loss of organic matter and topsoil needed to grow plants and keep our city green.

My recommendation: ban blowers. Let the landscape crews return to rakes and brooms. Encourage on-site mulching of leaves rather than blowing and bagging that sterilizes, erodes, and compacts the soil and kills trees.In your deliberations, please remember public health. We cannot enjoy good health if we live in a sick environment.

********
In 2006, Linda L. Creighton wrote about this topic for U.S. News and World Report. She even mentioned that Palo Alto, CA had banned blowers outright. One reason: "A single gas-powered leaf blower-and more than 2.5 million of them will be sold this year alone-can emit as much pollution in a year as 80 cars." She also cites the ear-splitting decibel level and the unnecessary cost.

Citizens for a Quieter Sacramento enumerates and quantifies many of the same offenses that I mentioned. They give more documentation than I do.

How many people have to get hurt by these contraptions before we change the laws?

Sphere: Related Content

Something peaked and the world changed – oil, recession, and transportation options

Unless several other things change fundamentally, the Texas Legislature’s efforts to expand solar-generated electricity might reduce some coal or natural gas consumption, but not oil. (Austin American-Statesman, “State warms to solar power, 2/2/09) Until plug-in electric hybrid cars or electric trains become commonplace, solar power will not replace a significant amount of petroleum. The most expedient and affordable way to reduce petroleum consumption – other than just staying at home – would involve replacing trips by car or truck with trips by electric-powered trains.

Jump starting the economy will not help matters much if the economic paradigm we still live by no longer fits the world we live in. (See President Obama’s agenda on Energy & Environment.) Does it really make sense to build roads and bridges for cars and trucks any more? If the economy could recover, those cars and trucks could not afford the fuel. Fuel prices collapsed because the economy did – businesses went bankrupt and people lost their jobs.

The price of oil – the basis for most liquid motor fuels – collapsed after July 2008 because $147/barrel proved disastrous for global commerce. The high price destroyed demand to such an extent that it pushed the already precarious economy over the edge and into recession. The recession depressed demand but did nothing to augment production. Since demand – and price – fell, the incentive to produce has disintegrated. One way or another – insufficient demand or reserves – supply will continue to dwindle.

Whether or not one believes in the imminent peak of world oil production or the peak as an historical fact, some kind of peak event occurred in 2008. Maybe we can call it a peak of irrational exuberance. At any rate, the world changed and we cannot go back. Prior to 1970, Americans resolutely believed that we could build a nation-wide transportation system based on motor highways. Or, at least GM, Ford, Exxon, Chevron, et al did. Since U.S. oil production hit its peak in 1971, we increased our imports of oil every year. Unless we dramatically curb demand (i.e. gasoline consumption), we can never eliminate our dependence on imported oil. If oil reserves still existed on U.S. territory, at merchantable prices, our highly motivated and enterprising petroleum geologists would have found it by now. What remains in domestic deposits costs more to produce than that which we now import. Otherwise, it would make no sense to import.

No amount of biofuels from corn, soy, cellulose, algae, or mushrooms will replace liquid motor fuels in the quantities we demanded prior to 2008. Synthesizing oil and gasoline from coal, tar sands, shale, or even natural gas will continue to lead us down the doomsday path of global climate change. The world has changed and we must adapt.

Whether the economy takes 2, 5, or 10 years to “recover,” it will never return to what we considered “normal” at any time in the past. The concatenation of crises with the economy, climate, food production, and ecosystem integrity demands that we change the way we see ourselves in the world. If we view the riches of the Earth as disposable, so we will also go.

As with any revolution, chaos makes the outcome very unclear. Nevertheless, a few things seem obvious enough to me now. We cannot afford to build both new highways and new railroads. Railroads cost less to build, use, and maintain than cars and trucks on highways. Don’t forget to include the cost of every vehicle when assessing the comparative costs. We can no longer afford a transportation system based on trucks for long-distance freight hauling or cars for routine commuting in urban areas. We need to shift the focus of our transportation network to trains immediately. Otherwise, the economy might never recover.

Sphere: Related Content