Harpers Ferry National Historical Park - Trees and Shrubs

Harpers Ferry National Historical Park by National Parks Service

Since 70% of the park is forested, it is no surprise that a wide variety of tree and shrub species occur here. Chestnut oak ( Quercus prinus ) is usually the dominant tree in the forest canopy on rocky soils of higher ridges such as Maryland Heights. Black oak ( Quercus velutina ) is also important on south, west, and east-facing slopes. Northern red oak ( Quercus rubra ) is found with chestnut oak on rocky, north-facing slopes, where eastern hemlock ( Tsuga canadensis ) was formerly prominent [see Pest subheading]. Red maple ( Acer rubrum ), black gum ( Nyssa sylvatica ), and flowering dogwood ( Cornus florida ) are frequent understory trees, while mountain laurel ( Kalmia latifolia ), black huckleberry ( Gaylussacia baccata ), Blue Ridge blueberries ( Vaccinium pallidum ) and deerberry ( V. stamineum ), and mapleleaf viburnum ( Viburnum acerifolium ) are common shrubs.

Lower elevation north-facing slopes with base-rich soils, such as those on the Catoctin and Harpers geologic formations, support a mixed mesophytic forest of northern red oak, white ash (Fraxinus americana ) , sugar maple ( Acer saccharum ), basswood ( Tilia americana ), hackberry ( Celtis occidentalis ), bitternut hickory ( Carya cordiformis ), slippery elm ( Ulmus rubra ), and tulip poplar ( Liriodendron tulipifera ). Shrubs of the mesophytic forests include spicebush ( Lindera benzoin ), hop hornbeam ( Ostrya virginiana ), American bladdernut ( Staphylea trifolia ), and pawpaw ( Asimina triloba ).

There are two extensive types of floodplain forests along the Potomac and Shenandoah Rivers: lower areas flooded on an average of once every one to three years have silver maple ( Acer saccharinum ) as a prominent component with associated species such as sycamore ( Platanus occidentalis ), green ash ( Fraxinus pennsylvanica ), and cottonwood ( Populus deltoides ); higher parts of floodplains have a diverse forest of sycamore, white and green ash, tulip poplar, bitternut hickory, hackberry, sugar maple, black walnut ( Juglans nigra ), and the locally rare Shumard oak ( Quercus shumardii ). Spicebush, pawpaw, American bladdernut, and American hornbeam ( Carpinus caroliniana ) are among the most common shrubs of floodplain forests.