Sleepy Hollow Cemetery has achieved Level 1 Arboretum Accreditation. As of August 2021 we have tagged 28 species of trees on the cemetery grounds: Tulip, Norway spruce, Norway maple, Black locust, White spruce, Eastern hemlock, Arborvitae, Horse chestnut, Douglas fir, Red cedar, Black oak, White cedar, Sycamore maple, Red mulberry, Blue spruce, White pine, Red maple, Austrian pine, Black birch, Black cherry, Bitternut hickory, Red oak, American beech, American elm, White oak, Sugar maple, Pin oak, Dogwood.