Courtesy Sondra Katzen, Chicago Zoological Society

The ArbNet Arboretum Accreditation Program and The Morton Arboretum are pleased to announce that the Chicago Zoological Society, which manages Brookfield Zoo, has been awarded a Level II Accreditation. By achieving particular standards of professional practices deemed important for arboreta and botanic gardens, the Chicago Zoological Society is now recognized as an accredited arboretum in The Morton Register of Arboreta.

At Brookfield Zoo, the Chicago Zoological Society has launched comprehensive efforts to connect urban families with nature and wildlife and to train informal educators on ways to integrate nature and science-based learning opportunities into their curricula. In addition, the zoo offers a walking map that identifies its many majestic trees across the 216-acre park that is home to more than 2,000 animals. The tree collection can be appreciated by guest as they stroll the zoo’s expansive walking paths.

That collection includes notable native trees not commonly found in landscapes, such as the pawpaw (Asimina triloba), which boasts fun foliage and banana-flavored fruit; common sassafras (Sassafras albidium), which (despite its name) is not commonly seen in “captivity,” and the shagbark hickory (Carya ovata), a slow-growing tree with beautiful bark. Unusual global finds include the caster-aralia (Kalopanax pictus), a showstopper from Asia; the Japanese whitebark magnolia (Magnolia hypoleuca), a standout with leathery leaf texture and highly fragrant flowers, and the Balkan pine (Pinus peuce), a threatened five-needle pine from the Balkan Peninsula. Interestingly, the zoo has both an American elm, an example of a species that was nearly wiped out by Dutch elm disease, and a Japanese Zelkova (Zelkova serrata), a beautiful tree often used to replace American elm but rare in our region.
In providing zoogoers up-close encounters with nature, the Society fulfills its lifelong mission of connecting the community with nature through educational programs, realistic exhibits and a constantly vibrant and flourishing landscape, including both native and nonnative trees.

About Chicago Zoological Society

The Chicago Zoological Society, which manages Brookfield Zoo, inspires conservation leadership by connecting people with wildlife and nature. The Chicago Zoological Society is a private nonprofit organization that operates Brookfield Zoo on land owned by the Forest Preserve District of Cook County. The zoo is open every day and yearly welcomes more than two millions guests. For further information, visit

About the ArbNet Arboretum Accreditation Program

The ArbNet Arboretum Accreditation Program is sponsored and coordinated by The Morton Arboretum in cooperation with American Public Gardens Association and Botanic Gardens Conservation International. This international initiative offers four levels of accreditation, recognizing arboreta of various degrees of development, capacity and professionalism. Accreditation is based on self-assessment and documentation of an arboretum’s level of achievement of accreditation standards. Standards include planning, governance, labeling of species, staff or volunteer support, public access and programming and tree science, planting and conservation. More information is available at