This is scientific American 60 second science. I'm Christopher Intagiyata.

In the fight to conserve tropical rainforests, here's a tool you don't often hear about.

Orange peals, specifically 12,000 tons of them dumped on the land.

You don't normally associate waste disposal with biodiversity benefits or something that's good for the environment.

Tim Truer is an ecologist at Princeton University. to be

something that's good for the environment.

Tim Truer is an ecologist at Princeton University

and he's talking about a unique conservation story.

It started in the early 1990s when an orange juice producer called Del Oro

set up shop near the Guanacaste Conservation Area in Costa Rica.

It's a region that contains several national parks and a wildlife refuge.

Del Oro needed somewhere to dump their orange peals, and the company also owned forested land, abutting the parkland, that it had no intention of cultivating.

So a deal was struck.

If Delorro donated its forested land, it could dump orange peel waste on degraded

pasture land within the conservation area.

A thousand dump trucks worth of orange peals were scattered on the land in 1998.

And within about six months, the orange peals had been converted from orange fields

into this kind of thick black loamy soil kind of passing through this pretty gross stage in between of kind of sludgy stuff filled with fly larvae.

The results of that influx of nutrient-rich organic material?

I couldn't even find the site the first time that I saw it.

He couldn't find it site the first time that I saw it. He couldn't find it because over

16 years the orange peel waste had sent the land on a journey to become vine-choked

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