The Cook Arboretum officially is a Janesville city park but is maintained and managed by the Janesville Public School District. It is the site of the Janesville Schools Outdoor Laboratory, where children learn about nature and natural resources, as well as embark on the trails. Eighty-five acres of its hilly terrain was designated as a park in 1968, followed by purchases in 1979 and 1987 and a recent land swap resulting in its current acreage. In 1986, the arboretum was officially certified as a School Forest and is one of the largest such properties in Wisconsin.
