A Garden of Nutrients

Tim Vanderpool, Jacob Chin photo

On a farm 30 minutes south of the UA campus, dust billows behind a big blue tractor on tawny fields stretching to miles of raw desert. At first glance, there is no clue that this is part of a groundbreaking student-run program that promises to revamp the way Tucson handles its food waste. But the UA’s Compost Cats are doing just that. 

“The original idea was just to compost food scraps from the Student Union,” says Chet Phillips, project director and a doctoral candidate in the UA’s Arid Lands Resource Sciences program. “And we now have memorandums of understanding with San Xavier [Co-op Farm, on the Tohono O’odham reservation], the Community Food Bank of Southern Arizona, and now the City of Tucson, where they’re bringing us what they call ‘zoo doo’ from Reid Park Zoo. By summer, we hope that city businesses will also have a composting option as well as trash and recycling.” 

The product of this hard work is gardeners’ gold: Nutrients in the decomposing food remain intact as the material is turned into compost, which can then be spread through the soil. Through the Food Bank, the Cats distribute the compost to low-income folks to use in backyard gardens and for agricultural projects at local schools. At the same time, the program keeps mountains of food scraps from local landfills. In just one day, the Cats can divert 10,000 pounds of produce, and to date, they have diverted more than 1.5 million pounds of organic waste.

The students working for Compost Cats benefit as well, earning a paycheck and gaining job skills. “Our students have done everything from business planning, marketing and financial planning, down to the actual farm work,” Phillips says. 

To Phillips, the reasons their work matters so much range from agricultural to environmental. He points to a study of a small-town landfill that revealed that 700,000 pounds of food was being dumped there each month. Once buried and compacted with other trash, food does not effectively break down, but instead adds methane to the atmosphere. “So we can take that greenhouse-gas producing waste,” Phillips says, “and turn it into local soil fertility.”