One of the Arboretum's most photographed collections, because people like to have their picture taken with the old collection sign pointed at them! (It will be replaced soon!) We have 3 species of hickory and 8 cultivars (Carya sp.) and 8 species and 10 cultivars of walnuts and butternuts (Juglans sp.). There are 35 specimens in the collection. Many of the nut trees are native but because of their tap root system they are impossible to transplant except as seedlings. Black walnuts, which are handsome trees, give off the compound Juglone from their roots which allow very few plants to grow beneath them. Therefore, it is not the best tree for the home landscape.