The Holden Arboretum, founded in 1931 and located in Willoughby, Ohio, has more than 3,500-acre of display gardens, horticultural collections and nature trails. It has a wide range of plants and gardens, a library, museum store and plant database. The museum has various gardens that include Display, Butterfly, Wildflower, Helen S. Layer Rhododendron and Blueberry Pond Area Gardens. It has a themed plant collection that includes several plants, such as alders, arbor vitae and false cypress, ashes, conifers and flowering crabapples. The museum also has other plants collection, including hollies, lindens, magnolias, and nut bearing and specimen trees. It additionally organizes various classes and events that include Yoga in Gardens, Orchid Basics Series Workshops, Holden Striders, Winter Blooms on Masa Paper and Wine and Cheese Night Hike.