The Holden Arboretum, in Kirtland, Ohio, is one of the largest arboreta and botanical gardens in the United States, with more than 3,600 acres, including 600 acres devoted to collections and gardens. Diverse natural areas and ecologically sensitive habitats make up the rest of the holdings. Holden's collections includes 9,400 different kinds of woody plants, representing 79 plant families. Wikipedia
