Smooth Aster

Aster laevis

Many people are familiar with and easily recognize asters, one of the most characteristic flowers of the autumn.  They are in the Asteraceae or Sunflower Family, and so have sunflower-like or daisy-like flowers with central clusters of tubular disc flowers surrounded by petal-like ray flowers.  The rays are white, pink, purple or blue.  Ox-eye daisy has fewer, larger white rays and blooms in the summer.  Daisy fleabanes have many more rays, which are white or pink, and bloom in the spring to summer.  Asters are thus easy to recognize by their daisy-like flowers and late blooming period.

Telling the different asters apart, however, is a real challenge.  There are many reasons for this.  First, there are a lot of asters, 250 or more species.  Second, although there are many species in the Old World, and a few in South America, most are North American, and the greatest diversity is right here in the eastern United States. Third, many species are highly variable, that is the leaves in the same species may come in different shapes or different sizes, or the flowers may be different colors, and so on.  Finally, many species hybridize, producing plants that are intermediate between their parents.  So far, thirteen species of aster have been reported from Wildwood, making it one of the most diverse genera of plants in the park. 

Smooth aster is one of the most beautiful.  It has rays that are dark blue to purple, rarely white.  There are about 15 to 25 rays on each head, and each head is about 3/4 to one inch wide.  The leaves are very variable in size and shape, but are usually more than 1/2 inch wide.  The leaves also vary in the length of the leafstalk, which can vary from moderately long to non-existent.  The leaves are thick and smooth to the touch, and the stems are also smooth.  Other common blue species of aster have hairy stems and leaves.

Smooth aster is found in dry fields and open woods over most of North America, from New Brunswick to British Columbia and the Yukon Territory, south to California, Mexico, and Florida.  In Wildwood it likes open areas along Wildwood Drive and at the edges of the woods.

The genus name, Aster, comes from the Greek word for "star" and refers to the rays flowers radiating from the central disc.  The species name laevis means "smooth."  The genus Aster has always been a large genus with many quite different plants.  Recently, DNA evidence has led some scientists to split it into many smaller genera, although this change has not had time to make it into all the guidebooks and other references yet.  Most of the familiar asters are now in the genus Symphyotrichum; smooth aster, for example, has been renamed Symphyotrichum laeve.  This name comes from the Greek symphysis meaning "junction" plus trichos meaning "hair," and refers to the jointed bristles on a European species in the new genus.