Do you ever wonder what happens to the food left over in Spangler Dining Hall?
The morning of Saturday, March 26 a group of people from across the Harvard community took an hour-long bus ride up north to visit Brickends Farm in Hamilton, MA to find out. The tour was sponsored by Harvard FMO Recycling and the 20 tour-goers included students from HBS, HLS, and Harvard College as well as staff from across the University. Everyone was outfitted in their boots because Farmer Peter Britton, owner of Brickends Farm, said we would need them while walking around his muddy acreage.
Farmer Britton, a retired high school English teacher, is using the 5 acres of land he inherited from his family to turn waste into a valuable and renewable resource: compost.
Compost is the product of a biological process during which naturally occurring aerobic microorganisms break down organic materials (such as food waste) into nutrient-rich material that can be used to improve soil quality. The end product is purchased by local farms and is used as a soil conditioner for crops and plants. The retail price is approximately $30 per cubic yard.
Every year local businesses and universities, including Harvard University, truck in tons of yard waste and unused food. Food scraps from nearly all food preparation facilities at Harvard are composted and roughly 4,000 tons of compostables are recovered annually.
“That organic material that we see as misallocated waste in our society can be turned into a product that people want. That’s organic matter that goes back into the soil,” Peter said.
Some commercial farmers can rely exclusively on compost to meet the soil needs, and stop importing chemical fertilizers that are generally harmful for the environment.
A variety of materials may be used for composting, including kitchen scraps, leaves, grass, weeds, and animal manure. The process is fairly simple: let the compostable material sit in a pile for roughly a year and turn every so often. Sometimes the decomposition process is aided by shredding the plant matter, adding water and ensuring proper aeration by regularly turning the mixture. Aerobic bacteria manage the chemical process by converting the inputs into heat, carbon dioxide and ammonium. The ammonium is further converted by bacteria into plant-nourishing nitrites and nitrates. Temperatures during the composting process can reach up to 140 degrees F!
Peter is particularly proud of the “mobile greenhouse” built onto a trailer, which is heated by compost (i.e. microbial digestion of organic scraps). The greenhouse is part of Brickends’s support for CSA gardens (Community Supported Agriculture) on a portion of the farm.
If compostable material goes into a landfill does it just decompose and cause no harm? No. Organics degrading in landfills without oxygen emit methane which is a greenhouse gas that is 21 times more potent than carbon dioxide. Composting adds oxygen to organic waste, so it emits only carbon dioxide as part of the natural carbon cycle during decomposition. Plus, compost saves money by reducing trash removal costs and reducing the need to purchase chemical fertilizers.
The use of composting to turn organic waste into a valuable resource is expanding rapidly in the United States and in other countries as landfill space becomes scarce and expensive, and as people become more aware of the impacts they have on the environment. In ten years, composting will hopefully be as commonplace as recycling aluminum cans is today, both in the backyard and on an industrial scale.