In 2022, the Cincinnati Zoo and Botanical Garden Sustainability Team, led by Stephanie Ritchie and Mallory Geresy, won a Recycled Ohio EPA grant to acquire equipment for their award-winning horticultural team. The Green Waste Recycling Program (GWRP) at the Cincinnati Zoo treats horticultural waste and debris to create value-added mulching products for use in gardens and community projects as part of its zero-waste initiative. was introduced.

The purpose of this award was to promote GWRP and provide gardening teams with a towable Bandit Model 1425 Mini Beast horizontal grinder. This machine reduces the amount of green waste by more than 75% by processing bamboo stalks, elephant grass, tree branches, logs, herbaceous waste, wood waste, pallets, etc. This creates a ready-to-use product, uses minimal space, and eliminates waste. Green waste has to be hauled (reduced emissions and transportation costs), offsetting part of the annual mulch purchase can reduce the need for irrigation.

Our company produces approximately 1,080 cubic yards of green waste annually, which is approximately 25% of our total waste volume. Historically, we have managed this waste in large mulching piles on-site or, in special cases, by third parties transporting it to off-site mulching facilities. However, with the development of new animal habitats, there is no more space on the site for large stakes.

The Cincinnati Zoo will pilot the Mini Beast in the spring of 2022, using virtually any waste it has tried as input, including bamboo stalks, elephant grass, tree branches, logs, herbaceous waste, woody waste, and pallets. The process has been proven successful. About 60 cubic yards of waste was processed in about 4 hours. A volume reduction rate of approximately 75% was observed. Using a 2 inch round screen allowed us to produce much finer mulch than the purchased mulch. We were very pleased with Mini Beast’s performance and versatility, and decided on a key role in GWRP.