The trembling aspen is a slender, medium sized tree common to forested areas across Ontario. The smooth, grayish-white bark (sometimes with tones of green or yellow) is a noteworthy attraction against darker wooded areas. The bark becoming rougher with age especially around the trunk base. Leaves can turn an impressive yellow, orange, or red in the fall. Their flattened leaf petioles cause them 'tremble' or 'quake' in the wind, hence its name.

Trembling aspen stands form some of the largest single organism biomass collections in the world. Its widespread, shallow root system can form massive colonies in disturbed areas where suckering occurs. New saplings com up to replace older trees of the colony when they die.

Like other poplars, trembling aspen is fast growing and weak wooded though the timber is useful for various products. It is also an important ecological forest tree as it provides habitat for many kinds of birds as well as large and small mammals.