Lodgepole pine is the most common tree at Blue River, although its population has been severely reduced by the mountain pine beetle. Other common native conifers are Douglas-fir, Engelmann spruce, subalpine fir, western hemlock and western red cedar. Among deciduous trees, the black cottonwood is largest; trembling aspen and paper birch are also prominent. Non-native trees which may be seen in Blue River include green ash, littleleaf linden, silver maple, and Norway maple. Sugar maple, burr oak, northern red oak and butternut formerly thrived at the CNR Gardens.