Volunteers recently began installing stubby, conical composters called Green Cones in the backyards and gardens of Belfast residents. The effort is part of a part of a yearlong pilot program, though project organizer Mark Dittrick said the cones have a long and successful record elsewhere already.

Green Cones differ from traditional composting bins in two ways. Because they use an accelerated aerobic process involving heat and air circulation, they are capable of breaking down meat, dairy, bones and other organic waste that would otherwise turn rancid and attract animals. They purport to do this without producing odors.

Structurally, a Green Cone consists of a waist-high, truncated green plastic cone with a perforated black plastic basket attached to the bottom. The translucent green upper portion conceals a second, slightly smaller, black cone inside. Between the two layers, air naturally warms and circulates, speeding the breakdown of the food inside.

“The idea is: make aerobic bacteria real, real happy and they’ll be eating this stuff up that we put in there,” said Dittrick.

Installing one involves digging a hole deep enough for the basket to be fully below ground, lining the hole with gravel to facilitate drainage, then covering the basket, leaving the namesake top portion exposed. Kitchen waste can be thrown in by opening a lid on the top.

On the down side, anyone looking for “black gold” in a Green Cone will come up empty handed. The composters don’t produce any useable fertilizer. Instead, the decomposed material leaches out of the submerged base of the composter into the surrounding soil.

According to Dittrick the effect is very beneficial to surrounding plants. He cited a study comparing the growth of two trees, one planted next to a Green Cone. That tree grew twice as fast, he said.

Earlier this year, Connecticut distributor Signature Marketing donated 40 Green Cones and around a dozen Garden Gourmet composters — the Cones’ somewhat less exciting garden waste counterpart — to the city for the pilot project. The cones arrived recently and are being staged in a High Street storefront across from City Hall. Dittrick packed as many of the cones as he could into the display window and the effect is striking — part minimalist installation, part Terracotta Army.

On August 4, Dittrick and four other volunteers were in the side yard of Cedar Street resident Janis Hogan, installing the first of the city’s Green Cones next to a group of raised planting beds. The beds were a Mother’s Day gift from Hogan’s husband and son-in-law. Hogan said she had always wanted to compost kitchen waste but couldn’t because of skunks.

Hers were technically the second Green Cones installed in Belfast — the first were at the Crocker Road offices of G-O Logic architects. Volunteers plan to distribute the 40 Green Cones around the city, two per household. An open call for participants returned enough interest that Dittrick said he is no longer seeking households to be a part of the project.

Green Cones have been around for twenty years. The distributor of the cones, Great Green Systems, lists distributors in England, Ireland, continental Europe, the U.S., Canada and Australia.

Central Vermont Solid Waste Management District recently created Zero Waste Inc., a nonprofit, to promote the use of Green Cones by offering them at deep discounts. CVSWMD got the idea from the Nova Scotia town of Annapolis Royal, population 600, whose “zero waste” program — Green Cones in every backyard — Dittrick helped create.

“We’re calling this a pilot program,” he said of the project in Belfast, “But this has been proven again and again.”