Which tree characteristic is associated with fall color?

The characteristic most directly associated with fall color in trees is leaf pigmentation. During the growing season, chlorophyll gives leaves their green color, but as temperatures drop and daylight decreases in the autumn, chlorophyll production slows and eventually halts. This allows other pigments present in the leaves, such as carotenoids (which produce yellow and orange hues) and anthocyanins (which create red and purple tones), to become more visible. The variation in these pigments among different tree species is what leads to the diverse and vibrant colors seen in fall foliage.

While flowers, leaf structure, and growth habit may play roles in the overall aesthetics and biology of a tree, they do not significantly influence the striking changes in color that occur in the leaves during the fall season. Therefore, leaf pigmentation is the key factor that determines the vivid and varied fall colors we observe each year.