Widely recognized as the site of historic research in ecological restoration, the Arboretum is home to some of the oldest and most varied collection of restored ecological communities in the world, including tallgrass and shortgrass prairies, oak savannas, woodlands, and wetlands.

There are also two garden collections: Longenecker Horticultural Gardens, the state's premier collection of ornamental trees and shrubs, and the Wisconsin Native Plant Garden, designed to teach and demonstrate the use of native plants in home gardens for biodiversity, habitat, beauty, and sustainability.

The Arboretum offers 17 miles of walking trails and 4 miles of biking road as well as hundreds of learning and volunteer opportunities.