An arboretum in a general sense is a botanical collection composed exclusively of trees. The Worcester Garden Club, in collaboration with the Worcester Department of Public Works & Parks has created an arboretum of Asian Longhorn Beetle-resistant trees. On Arbor Day, 2012, the Club and the Worcester Forestry Operations planted 14 young trees representing 12 different species resistant to the ALB. They complement the existing trees that are either resistant or host to the invasive beetle. Together, they establish the Green Hill Park Arboretum which has a specific purpose: to teach visitors about selecting the right tree and planting it in the right place in their landscapes.