This tall, small-flowered native aster is found in much of North America except for the far north. It is now a common sight growing in a variety of man-disturbed habitats. The leaves of this perennial aster are slender, short-stalked, sharp-pointed and hairless. They are either toothless or with only a few teeth and have blunt bases. 

This species is most easily identified by the abundant white ray flowers (petals)—20-40 per flower head. Each flower head is ½ to ¾ inch in diameter. The central disk flowers are yellow and turn pinkish with age. The flower bracts are narrow and green tipped. The blooming period is August to October. The flowers attract a variety of insects, especially bees, flies and wasps.

The main stem is grooved and branches occasionally. The stems also have lines of white hairs. Often there are groups of small leaves where the stem branches. The fruit is a dry and seed-like achene and is tipped with tufts of hair to aid wind distribution. The new stems are green in color, but turn brown and woody with age, especially in the larger plants. These older, woody stems are smooth. This aster can grow up to 8 feet tall depending on growing conditions. 

This species may form colonies by spreading from underground rhizomes and can be quite showy. In many areas, however, it is treated as a weed, especially if growing in an agricultural setting.