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Ken Reveals the Ins and Outs of His Own Compost Pile

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Ken Reveals the Ins and Outs of His Own Compost Pile

Photo by Ken Davis

So you’ve gone green—you’re recycling, and you’ve even downsized that gas-guzzler. But, come on. If you really want to be light on the earth, there simply has to be a compost pile in your backyard or even right in your kitchen. But composting is never that simple. For many people that pile of dirt, leaves and food scraps can lead to years of frustration and failure. So Ken Davis, who has his own sordid history with composting, set out to find the secrets to creating a good pile. A word of warning to more sensitive listeners: this report deals frankly with the existence of critter poop.

This is my backyard compost pile. This year, for the first time, it seems to be really working. I’m really pretty excited about it. It stays nice and warm, and now when I put chopped up weeds and kitchen wastes in here, they disappear. I mean really just disappear, in a few days. But it wasn’t always like this.

Like the time I tried to go high-tech and spent a ton of money on a Compostumber. I’d throw grass and leaves into it and go out every morning and give this big old barrel a few turns with the special crank and, weeks later there’d be a black, oozy stinky mess in there.

So I decided to go back to school.

ambi: hi, hi how are you, etc.

SLATE: This is the ecology lab where ecology classes are taught.

Jennifer Slate’s a biology professor at Northeastern Illinois University. She uses compost as a teaching tool in her biology classes, she fills plastic storage boxes with kitchen scraps and newspapers and has her students bring in handsful of soil from their yards. It’s the perfect place to come for advice.

DAVIS: Well, here, I brought you a bucket.
SLATE: Awesome.
DAVIS: So this is compost from my yard, just one shovel-full taken, it’s kinda muddy cause it got wet last night.

Slate spreads a small sample of my compost across a piece of glass and peers down into it.

SLATE: This is what’s called a stereo microscope.
DAVIS: Let me pull up a chair here.
SLATE: You gotta look in there. They’re scurrying away really quickly. We’ve got little insects.
DAVIS: It’s like looking into a whole different world in there, I mean there’s just stuff moving everywhere.
SLATE: Yea. The name of those little insects scurrying away are called springtails and they’re called that because if you touch their tail end with forceps or the tip of a pencil they will spring up. They’re so fast.

They’re fast and they’re a good sign.

SLATE: What you wanna do with a compost bin is simulate the natural soil environment. Because compost happens every day in forests, in your garden soil, even in your front yard, in any kind of soil, dead material is being broken down.

And what’s causing all that break down is what the professor calls, with her academic flair, critters. Specifically critters digging into a good meal.

SLATE: There are lots and lots of little insects who survive on this plant material. And they eat it. And that’s why it disappears.

Now this might sound ridiculous but for decades I thought when you threw this plant material into a pile, it just rotted. Instead the typical compost pile is actually a massive construction, or should we say, demolition site, populated with millions of laborers. But that only becomes obvious under a microscope.

SLATE: You have critters eating plant material, and then bigger critters eating those critters, and as all that material works through that, their digestive tract, it gets broken down into smaller matter, and for lack of a better word, it’s pooped out.

So that’s my first lesson. Compost doesn’t just happen. It’s manufactured. By critters.

DAVIS: What is that thing? Is that some kind of living thing there?
SLATE: Yeah, that might be a slug. Oh, my god, you gotta see this under the microscope...
DAVIS: About the size of a, looks like a dog in the microscope. And I don’t wanna get too personal but it looks like maybe he’s actually excreting something.
SLATE: You’re right. He’s in the process of…
DAVIS: of making compost.
SLATE: I think you’re right. There’s something coming out of its tail end. Poor guy, we interrupted his business.

And there it is. Lesson Number Two. All compost is critter poop. And the happier you make your critters, the more they eat, the more they reproduce, and, well, poop.

SLATE: They need it to be moist. They need it to be dark. They need it to be fairly warm. And they need to have plenty of food matter. Oh, oh, and they need oxygen.

So that Compostumbler I spent all that money on? The one that never worked? That’s because it was a closed system. Probably some bacteria in there, but little else in the way of critters.

SLATE: Your compost bin is a little ecosystem, and there’s bacteria, there’s organisms eating the bacteria, and there’s organisms eating those organisms, as well as the compost, you’ve got a whole community in there.

So, fellow gardeners. If you’ve been frustrated by compost that never seems to cook, take heart. You’re running a kind of resort here, and your guests have demands. Make sure that your container if you use one has enough openings to the ground to let the critters in. Turn the pile occasionally to let in some air, and provide a nice balance of green stuff, dead leaves and other organic wastes. And you need plenty of worms in there, because they eat the most, and their castings are the most valuable.

And despite all those demands, never consider yourself above the critters because after all one day you might be providing the feast.

SLATE: Eventually all of the nutrients get recycled and that’s what allows new plant growth.
DAVIS: And then we eat the plant growth and…
SLATE: Absolutely
DAVIS: And eventually we end up in the ground and they eat us.
SLATE: Yeah. Well, yeah

Food for thought.

For Chicago Pubic Radio, this is Ken Davis.

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