The Fort Stevenson State Park Arboretum is an arboretum located near the campground at Fort Stevenson State Park [] on the north shore of Lake Sakakawea approximately 3 miles (5 km) south of Garrison, North Dakota.
The arboretum contains over 50 native and non-native trees, shrubs, wildflowers and grasses, including Eleagnus angustifolia, Juniperus scopulorum, Salix exigua, and Ulmus pumila.