Quaking aspen
Utah's state tree, whose groves are often one plant joined underground.
Quaking aspen is Utah's official state tree. Its leaves hang on long, flattened stalks that make them flutter in the wind, and they turn bright yellow to orange in fall. The bark is smooth and greenish white to cream, furrowing on older trunks.
Aspen grows in cool, moist places at higher elevations. After a fire or other disturbance it sprouts from the roots, so a grove is often a clone: many trunks, genetically identical, on one root system. USU Extension says aspen does poorly in the heat and dryness of Utah's lower valleys.
Seeing it
Fall color depends on elevation and the year; there's no single statewide peak.