House Grounds Gardens Great Tree Planting Fields Library & Herbarium The Horticulture Library and the Herbarium are located in the Hay Barn complex near the main parking lot. Both facilities serve visitors interested in horticulture. The library contains over 7000 volumes of horticulture publications and related topics. The Herbarium contains over 10,000 dried and mounted plant specimens available for study purposes. For more information please go to Planning Your Visit.