Two Lessons in Practical Ecology

These days, the news coming out of America’s political and financial centers evokes the same sort of horrified fascination that draws onlookers to the scene of any other catastrophe. Investors spooked by the Fed’s willingness to pay for deficit spending by printing money are backing away from US debt, and the interest the US government has to pay on its bonds has accordingly gone up, gaining a full percentage point in the last month and putting pressure on other interest rates across the board.

In the teeth of this stinging vote of no confidence from the bond market, the Obama administration and its Republican allies in Congress – chew on that concept for a moment – are pushing through another round of spending increases and tax cuts that the government doesn’t have the money to pay for. The ratings agency Moody’s has warned that if the current spending bill is passed, it will have to consider downgrading the once-sacrosanct AAA rating on US government debt. Exactly how the endgame is going to be played is still anybody’s guess – runaway stagflation, a hyperinflationary currency collapse, and a flat-out default by the US government on its gargantuan public debt are all possible – but there’s no way that it’s going to end well.

All this makes the topic of this week’s post particularly timely. Across the industrial world, people have come to assume that they ought to be able to buy ripe strawberries in December and fresh oysters in May, and more generally food in vast quantity and variety on demand, irrespective of season. That assumption relies on using wildly extravagant amounts of energy to ship and process foodstuffs, and that by itself renders the eating habits of the recent past an arrangement without a future, but these same habits also depend on a baroque global financial system founded on the US dollar. As that comes unraveled, an old necessity most of our grandmothers grew up with – home processing and storage of seasonal foods – will become necessary once again, at least for those who don’t find scurvy and other dietary deficiency diseases to their taste.

Food storage is a subject that calls up strong and often contradictory emotions, and sometimes inspires actions that don’t necessarily make much sense. Rumors are flying just now in some corners of the peak oil community, for example, that the sales freeze-dried food has spiked so sharply in recent months that suppliers are unable to keep up with the demand. This may well be true, but if so, it shows a certain lack of common sense; unless you plan on living out of a backpack during a financial crash – and this is arguably not a good idea – there are many better and cheaper ways to make sure you have some food put by to cope with breaks in the supply chain.

Nor is food storage really about stashing food in a cellar in order to ride out a crisis. A century ago, nearly everybody in America processed food at home for storage if they could possibly do so, for reasons much more down to earth than expectations of catastrophe. They did it primarily because the foods available year round in a temperate climate typically don’t provide a balanced diet, much less an inviting one. Absent the energy and financial systems that make it look reasonable to fly fresh food from around the world to stock supermarkets in the United States throughout the year, good sources of vitamin C are mostly to be had in the summer and fall, meat tends to show up in a lump at slaughtering time in October and November, and so on; if you want these things the rest of the year, and you don’t have a functioning industrial economy to take care of that matter for you, you learn how to prepare foods for storage in season, and keep them safely stored until wanted later on.

The ways that this can be done, interestingly enough, make a very good lesson in practical ecology. To keep food in edible condition, you have to engage in what ecologists call competitive exclusion – that is, you have to prevent other living things from eating it before you do. Your main competitors are bacteria and other microorganisms, and you exclude them by changing the habitat provided by the food until it no longer provides the competition with the resources it needs to survive.

You can do that by changing just about every ecological variable you can think of. You can make food too cold for bacteria to survive; that’s freezing. You can make food too hot, and keep it enclosed in a container that won’t let the bacteria back in when the food cools down; that’s canning. You can make food too dry; that’s drying. You can change the chemical balance of food to make it indigestible to bacteria, but not to you; that’s salting, brining, smoking, corning, and pickling, among other things. You can get sneaky and keep food alive, so that its own immune system will prevent bacteria from getting a foothold; that’s root cellaring, and a variety of other tricks commonly used with cold-hardy vegetables. Alternatively, you can get even sneakier and beat the bacteria to the punch by deliberately infecting food with a microorganism of your choice, which will crowd out other microbes and change the food in ways that will leave it in edible condition for you; that’s fermentation.

Which of these is the best option? Wrong question. Depending on where you are, what foodstuffs and other resources you have to hand, and how long you expect it to take for various parts of the current order of things to come unraveled, almost any mix of options might be a good choice. It will almost certainly have to be a mix, since no one preservation method works best for everything, and in many cases there’s one or another method that’s the best or only option.

It’s also wise to have a mix, because methods of preserving food differ among themselves in another way: some are much more functional in a time of energy shortages than others. If your food storage plans revolve around having a working freezer, you had better hope that the electricity remains on in the area where you live, or you need to make sure you have a backup that will function over the long term – and no, a diesel generator in the basement and a tank of fuel doesn’t count, not after the first few weeks of fuel shortage. That doesn’t mean that blanching and freezing some of your homegrown garden produce is a bad idea; it means you need to have something in place to power the freezer well before the brownouts start to happen, or you need to be prepared to shift to another preservation method in a hurry, or both.

This points to a second good lesson in practical ecology that can be learned from food storage, though this one’s a lesson in practical human ecology. Technologies – all technologies, everywhere – vary in their dependence on larger systems. When comparing two technologies that do the same thing, the impact of their relative dependence on different systems needs to be included in the comparison; if technology A and B both provide a given service, and technology A is cheaper, easier, and more effective than technology B under ordinary conditions, technology B can still be the wiser choice if technology A is wholly dependent on an unstable system while technology B lacks that vulnerability.

This much should be obvious, though all too often it isn’t. It’s embarrassing, in point of fact, to see how often a brittle, complex and vulnerable technology dependent on highly questionable systems is touted as “more efficient” than some simpler, more reliable and more independent equivalent, simply because the former works somewhat better on those occasions when it can be made to work at all. Just as you don’t actually know how to use a tool until you can instantly name three ways to misuse it and three things it can’t do at all, it’s a waste of time and resources to buy into any technology unless you have a pretty good idea in advance of its vulnerabilities and the ways it tends to fail.

This sort of thinking can and should be applied throughout the green wizardry we’ve been discussing in the last five months or so of posts, but food storage is a very good place to start. Let’s say you’ve decided to blanch and freeze some of the vegetables from your backyard garden. That can be a good choice, at least if you can expect your electricity supply to remain stable for the next year or two; still, you owe it to yourself and your freezer bags of Romano beans to take a moment to work out the downside. What are the main sources of electricity in your service area, and how will they be affected by likely changes in fossil fuel prices over the next couple of years? How does electricity get to you from the grid, and is that connection vulnerable? When does your service area tend to suffer blackouts, and how long do they tend to last? Are there ways you can keep a freezer powered for the duration of a longer than average blackout? Does one of those ways seem like a sensible investment, or would it be smarter to shift to a less vulnerable method of storage?

More complexities slip in when you remember that there’s often more than one way to power the same process. You can dry food, for example, in an electric dehydrator, but in any climate that isn’t too humid, you can also dry food in a solar dehydrator. This is basically a black box with small holes in the top and bottom, covered with fine mesh to keep out insects, and trays of screen-door screening stretched on wooden frames inside, with the food spaced on the trays to allow air circulation. The sun heats the box, air flows in through the bottom and carries moisture away through the top, and the food dries with no other source of power. When you’ve got adequate and reliable electricity, an electric dehydrator is more convenient and reliable; when you have reason to think that electricity will be expensive, intermittent, or not available at all, the solar dehydrator is usually the better plan.

In many cases like this last, though, the best option of all is to have and use both – the more convenient and reliable technology while you’re still on the learning curve and the larger system that supports it is still there; the more resilient and independent system in a small way all along, so that you learn its quirks and can shift over to it full time once the more complex technology becomes nonfunctional. In the same way, it can make a good deal of sense to blanch and freeze garden produce while you’re still learning your way around using home-dried foods, or to can your pickles in a hot water bath while you’re still getting the knack of older pickling methods that don’t require airtight containers.

In a time of faltering energy supplies – not to mention the spectacular self-destruction of national finances – this sort of thinking can be applied very broadly indeed. The strategy of a staged disconnection from failing technologies, made on the basis of local conditions and personal, family, and community needs, offers a pragmatic alternative to the forced choice between total dependence on a crumbling industrial system, on the one hand, or the usually unreachable ideal of complete personal or community independence on the other. The backyard-garden methods discussed in earlier posts are founded on that strategy, and most of the energy conservation and homescale renewable energy production methods that will be central to the first few months’ worth of posts next year rely on it as well.

There’s a reason for this ubiquity: the strategy of staged disconnection is the constructive alternative to catabolic collapse. A society in catabolic collapse, running short of necessary resources, cannibalizes its own productive assets to replace resource flows, and ends up consuming itself. The strategy of staged disconnection is not catabolic but metabolic; it taps into existing resource flows before shortages become severe, and uses them to bridge the gap between existing systems that are likely to fail and enduring systems that have not yet been built. At the same time, if it’s done right, it doesn’t draw heavily enough on existing systems to cause them to fail before they have to.

That’s what could have happened if the industrial world had pursued the promising initiatives of the 1970s, instead of taking a thirty-year vacation from reality that cost us the chance of a smooth transition to a sustainable future. On the collective scale, that’s water under the bridge at this point, but it can still be done on the smaller scale of individuals, families, and communities.


Food preservation and storage are among the few subsets of green wizardry where old information can land you in a world of hurt. If you intend to take up canning, in particular, you need up-to-date information; for example, the relative proportions of sugar and acid in today’s tomato varieties, as compared to those fifty years ago, are so different that recipes that were safe then can land you with botulism poisoning, i.e., quite possibly dead, if you use them today. Your county extension service can point you toward accurate information on safe canning, and so can the current edition of the Ball Blue Book.

Not all methods of food preservation are as volatile as canning. Though it’s always wise to check for updated information, some of the classics are still well worth reading. My library includes Mike and Nancy Bubel’s Root Cellaring, Grace Firth’s Stillroom Cookery, Phyllis Hobson’s Making and Using Dried Foods, Carol Hupping’s Stocking Up III, and Stanley Schuler and Elizabeth Meriwether Schuler’s Preserving the Fruits of the Earth.