Brookfield Zoo Animals Munch on ComEd Tree Trimmings

BROOKFIELD, IL -- The animals at Brookfield Zoo continue to enjoy the nutritional benefits of browse -- the leaves, twigs and branches from trees -- provided by ComEd, one of the zoo’s staunchest supporters.

Since 2011, ComEd’s designated zoo crew makes two truck deliveries each week of 20 to 25 cubic yards of browse per truckload. The browse is from trees that are trimmed along overhead power lines located through the Chicago metropolitan area. Rather than mulching the browse, the trimmings are delivered to Brookfield zoo for the animals.

According to zoo officials, the animals greatly benefit from the nutritional value and enrichment the browse provides. The deliveries are part of a collaborative program between ComEd and the Chicago Zoological Society, which manages Brookfield Zoo.

The zoo’s staff nutritionist has provided ComEd with a list of approved plant and tree species. However, the animals’ favorites seem to be willow, mulberry, honey locust, and maple.

“The animals benefit in several ways from browse,” said Jennifer Watts, Ph.D., director of nutrition for CZS. “One is that it provides good dental health because the animals are able to chew on the branches, which helps release some of the tarter on their teeth. Additionally, it encourages natural behavior and provides enrichment.”

Gerenuks, a long-necked antelope found in the Horn of Africa, stand on their hind legs to reach for the leaves and the orangutans spend time peeling the bark off the branches. ComEd delivers the browse between spring to fall. Zoo staff vacuum-seals the trimmings, some of which are frozen so that the animals can continue enjoying their tree snacks in the winter.

ComEd employs 250 truck crews that trim trees along its high-voltage distribution circuits on a four-year cycle. The company trims approximately 9,000 miles of tree line each year. Additionally, ComEd performs targeted tree trimming between regularly scheduled maintenance to enhance reliability on sections that have higher incidences of outages caused by trees.

Removing overhanging branches improves reliability for customers and reduces the likelihood of tree limbs falling on power lines during storms that can cause power outages.

Learn more about the browse program in this informative video.