Written by Timothy Treuer
A story (but careful, there’s a twist):
In 1998, the Costa Rican Sala Cuarta (their highest judicial body) issued a ruling against a company that had dumped 12,000 tonnes of waste orange peels in one of the country’s flagship protected areas, Área de Conservación Guanacaste (ACG). The ruling came at the urging of some members of the Costa Rican environmental community, and studies had found elevated levels of d-limonene–a suspected carcinogen–in local waterways as a result of the company’s actions, raising tensions with neighboring Nicaragua over the possible pollution of their downstream eponymous lake. The court ruling demanded the immediate removal of the orange peels from where they lay–a site that some had labeled ‘an open air dump.’
A keen observer at the time would have noted one immediate hiccup with the court’s order: those 12,000 tonnes of orange waste? They didn’t exist anymore.
Six months of unfathomable ecstasy on the part of four species of flies had converted the mega pile o’ peels into several inches of black, loamy soil, smothering the invasive African grass that had previously dominated the heavily degraded corner of the national park. Oh, and d-limonene? Turns out it’s more of a cancer-fighter than a cancer-causer (See Asamoto et al. 2002 Mammary carcinomas induced in human c-Ha-ras proto-oncogene transgenic rats are estrogen-independent, but responsive to d-limonene treatment. Japanese Journal of Cancer Research), and can now be purchased on Amazon for $0.16/gram (note I do NOT endorse herbal supplements as a general rule–talk to your doctor if you or your transgenic rat suffer from mammary carcinomas).
See, the orange peel dumping was actually part of a grand plan hatched by rockstar ecologist turned conservationist, Dan Janzen (best known for his hit singles like ‘Herbivores and the Number of Tree Species in Tropical Forests’ and ‘Why Mountain Passes Are Higher in the Tropics’, but I prefer his deep tracks ‘How to be a fig’ and ‘Mice, big mammals, and seeds: it matters who defecates what where’). He and his partner Winnie Hallwachs had noted the following upon observing the development of a huge new orange juice processing facility on ACG’s northern border by a company called Del Oro: (1) most people don’t like peels in their orange juice, (2) megatonnes of orange peels probably weren’t the easiest thing to deal with on the cheap, and (3) of the 170,000+ species of creature in ACG’s forests, at least one probably would nosh some citrus rind. Upon discovering that Del Oro planned to construct a multi-million dollar plant to turn their waste into low-grade cattle feed, Dan and Winnie engineered the following plan:
- Dump orange peels on former cattle ranches recently incorporated into ACG.
- Fly orgy.
Amazingly this plan nearly worked perfectly! Del Oro was all over the idea of getting a little weird with ACG. After a promising test deposition of 100 truckloads of orange peels in 1996, Del Oro and ACG signed a contract wherein the park would provide waste disposal (and interestingly, formalized water provisioning and pest management ecosystem services that Del Oro enjoyed by virtue of being neighbors with a fat block of mountainous rain-, cloud- and dry forest) in exchange for donating a huge amount of still-forested land that they owned on the ACG border. Janzen threw in some ecological consultation and help in getting eco-friendly certifications as a sweetener. A seemingly beautiful win-win deal.
But of course, we can’t have nice things.
You may have already pieced together what happens next: after executing the first year of the contract wherein Del Oro trucked in ~12,000 metric tonnes of peels and pulp into a heavily degraded corner of ACG that was seemingly caught in a state of arrested succession, a rival orange juice company caught wind of the party, and did as one does when they get spurned by a guest list omission: they sued.
What seemed to get lost in the debates that raged at the time though, was what effect all these orange peels would have on the forest itself. Dan and Winnie had the intuition that killing off the fire-prone grass and adding nutrients to a plot of land that had been continuously trampled by bovid beasties for a couple hundred years would be a positive change for an aspiring forest, but that wasn’t a certainty.
After the fallout from the lawsuit and the court ruling, it’s understandable that Dan, Winnie, and ACG’s staff didn’t want to draw too much attention to the site (a couple of ACG officials nearly were thrown in jail for failing to adhere to the court order). They visited a few times early on to photograph the progress, and sent a botanist in the very early years to write down what species of plants were occurring in the fertilized area and the surrounding pasture, but other than that the project was more or less consigned to the quirky annals of ACG history (alongside such fascinating historical tidbits as a starring role in the Iran-Contra Affair–read the book Green Phoenix by Bill Allen for the full fascinating history of the park).
The reason I’m relating this story is that some collaborators and I started revisiting this site a few years ago, and we were so blown away by what we saw that we had to tell the world. The area where the orange peels had been? It had become just about the lushest forest I’d ever seen. Literally, vines on vines on vines. And the surrounding pasture? Still pretty much looked the same as in old photos.
In the summer of 2014, I set up Princeton senior thesis student Jon Choi ‘15 at the site, and let me just say, he scienced the crap out of it. We set up some vegetation transects and developed a soil sampling regime, and then he went full Tasmanian Devil in a labcoat. We’re talking camera traps, audio recorders, pitfall traps, and theoretical modelling of ecological state transitions–the whole nine meters. It truly impresses me that he managed to say so much about what ultimately boils down to a very simple observation: orange peels jump-started forest recovery–where there would otherwise be a stunted savanna, there’s now forest so thick you literally have to hack your way through with a machete.
After a few years of trying to distill this work into something palatable to reviewers, journal editors, and our team of co-authors, we are proud to finally drop our LP: ‘Low-cost agricultural waste accelerates tropical forest regeneration,’ available exclusively from Restoration Ecology.
In all seriousness, I really do believe there’s an incredibly exciting idea at the core of this project: it wasn’t just a win-win initiative. It was win-win-WIN. Carbon was sucked out of the atmosphere, biodiversity was increased, and soil quality improved. All FOR A PROFIT! Despite this, we couldn’t find a single other example of ag waste being used to speed forest recovery. We hope that changes. The world really shouldn’t contain both nutrient-starved degraded lands and nutrient-rich waste streams.
Tim is a PhD candidate in Ecology and Evolutionary Biology studying large-scale tropical forest restoration. More broadly, he is interested in the effective communication of and policy solutions to complex environmental challenges in an era of global change. He’s on Twitter (@treuer) and tumblr (treuer.tumblr.com).