Sunday, May 3, 2009

Fire - Visible and Invisible

Fire. Essential and dreaded. Fire has historical tendrils back to primeval times when people first discovered how to make fire when needed. Fire also includes the combustion and flames of a gas stove and oven, campfires, propane-fueled lanterns, and barbecue briquettes. All welcomed, desired.

Every garden is always on “fire”—without flames. Combustion is the oxidation of carbon-based materials which usually produces a flame. Garden “fires” are usually invisible, slow, and important. A single teaspoon of soil contains over one million of the soil’s beneficial bacteria alone This does not include: nitrogen-fixing soil algae, microbes, beneficial fungi and many other useful life. Each consumes various life-forms or inert elements and releases very minute amounts of heat into the soil. Like an aerobic workout, soil heats up—only in extremely tiny amounts.

Combustion in the compost bin also is at a lower temperature than a visible fire. Microorganisms feed on the carbohydrates; the carbon. The warmth of a well-made compost pile is tangible garden low-grade combustion. When the first nips of frost arrive, a compost made of fallen leaves, green lawn clippings, manure and kitchen scraps (I send all my kitchen compostables to an earthworm bin.) sends its wisps of warm fog to rise above its mass.

Only the fanatic composter runs the risk of spontaneous combustion. The pile has to be very large. And it rarely bursts into flames, but usually smolders like a coal mine "fire." Tim Dundon aka Zeke the Sheik (the compost king), of Los Angeles County, accumulated a compost pile over 17 years which reached the gargantuan size of 40 feet tall and up to 200 feet long. Twice in one month the pile spontaneously burst into flames and smoke, and the fire department arrived to douse the flames. While Zeke defends composting as "the key of energy that will eventually set mankind free from misery and gravity," I'd say his pile shows what happens when a zealous intellect elevates a natural process to unnatural proportions. He turned a beneficial process into a hazard.


Visit Robert Kourik's web site to learn about my other gardening books.


1 comment:

joe said...

I seem to recall that the guy at the Berkeley Marina recycling green waste years ago had a big fire too that burned his piles up.