There are many reasons we ask Glenstone’s visitors to stay on the trail. Primarily, we want to keep our native plants and animals from getting trampled, but another reason is the presence of another native plant: Toxicodendron radicans, otherwise known as poison ivy. Believe it or not, though it is not desirable for a home landscape, poison ivy is native to the eastern United States. It most commonly presents as a hairy, woody vine. Though it is infamous for the urushiol oil in its leaves and stems (the chemical that causes allergic reactions and itchiness in many humans), poison ivy plays an important ecological role. In particular, its white, waxy berries are a valuable winter food source for more than 60 bird species, including woodpeckers, thrushes, and quail, none of which are affected by urushiol. Deer and other mammals also dine on the plant. At Glenstone, poison ivy can sometimes be seen along the Woodland Trail growing up into the canopy of trees. Look carefully, though, as it is sometimes confused with the native (and harmless) Virginia creeper (Parthenocissus quinquefolia), which has leaves in groups of five, as opposed to poison ivy’s famous groups of three. Other common poison ivy lookalikes include box elder (Acer negundo) or Jack-in-the-pulpit (Arisaema triphyllum): though neither of these are vines, they do have prominent leaves in groups of three and can be low-growing, though box elder will eventually mature into a medium-sized tree. 

–Kevin McDonald