Common Name: Aster, Starwort, Michaelmas daisy (U.K.), l’oeil de Christ – eye of Christ (France) – The appearance of the flower with its yellow center and circumferential rays are reminiscent of a star, which is aster in Greek. There are many varieties. The one depicted above is the New England Aster.
Scientific Name: Aster was the original genus name. Recent DNA testing has separated the North American flowers in ten new genera (discussed below). The New England aster depicted above is in the genus Symphyotrichum with a specific name novae angliae – a direct Latin translation of New England.
Potpourri: The Asteraceae or Aster family is one of the largest taxonomic groupings of vascular plants with over 20,000 thousand species in over 1600 genera worldwide. Many, but by no means most of the species are North American; the USDA Plants database lists 4846 taxa in 477 genera (taxa is the plural of taxon, an element of a classification structure). In the 19th Century, all aster-like florae were grouped into the genus Aster by the taxonomists George Bentham and Joseph Hooker with the publication of the seminal three volume reference Genera plantarum ad exemplaria imprimis in herbariis kewensibus servata definita between 1862 and 1883. This arrangement persisted until the advent of recombinant DNA analysis to determine the phylogeny, or evolutionary history, of the species. The DNA sequencing of 80 species of aster revealed that North American asters are on a separate evolutionary line from Old World asters. Based on this analysis, there are now ten genera of North American asters: Symphyotrichum (90 species) is the most common; flowers in the original genus Aster are mostly Eurasian. It should be noted that most field guides, including the National Audubon Society Field Guide to North American Wildflowers and Newcomb’s Wildflower Guide continue to list all asters in the genus Aster.
The family Asteraceae is also known as Compositae, or the composite family. All of the flora in the family, which includes daisies, sunflowers, goldenrods and fleabanes in addition to asters, have a composite structure. The term composite implies a structure composed of individual assembled parts. A composite flower isn’t a flower, but a combination of many individual flowers. The central disc or capitulum is comprised of many individual disc flowers called florets. The surrounding “petals” are actually individual ray flowers that have involuted to the extent that the corolla is on only one side and is shaped like a strap. The (mostly) sterile ray flowers are imbricated so that the effect is one of overlapping petals around the central disk. The evolutionary success of the composite family is evidence of the success of the arrangement. The disc flowers are tubular with the stamens (pollen producing male structure) forming a cylinder around the stigma (top of female pistil that encloses the ovules). Insect pollinators are guided by the surrounding contrasting ray flowers where they are attracted to the olfactory disc flowers that sequentially bloom, producing the quintessential nectar that is their quest. The frequent arthropod visits to the tubular pollen-lined florets almost guarantee cross pollination and fertilization resulting in the eventual production of myriad achenes, which are commonly called seeds, to propagate the species.
The diversification and global range of the asters has inspired some scientific speculation as to the underlying reason. In addition to the prodigious seed production machinery of the capitulum, asters store carbohydrates in the form of short chain fructose molecules called fructans that are sustaining in the dry conditions that is acharacteristic of their habitat preference. In addition, they produce a diverse set of compounds called metabolites during the cell growth and reproduction process (metabolism). It is hypothesized that aster diversification began in the Eocene Epoch about 50 million years ago in South America and extended to Africa and Eurasia in the Oligocene Epoch 20 million years later. It is doubtless true that whatever the mechanism, asters adapt and evolve to the extent that botanists are driven to extremes in establishing species distinctions, resulting in a ubiquity of names that range from Arrow-leaved Aster to White Wood Aster. Pictured is the Heart-leaved Aster.
Asters have long been well-known to the Eurasian and Native American peoples. The noted Roman poet Virgil wrote of the starwort or aster in his four volume book of poems Georgics, which preceded The Aeneid:
There is a meadow-flower by country folk
Hight star-wort; ‘tis a plant not far to seek;
For from one sod an ample growth it rears,
Itself all golden, but girt with plenteous leaves,
Where glory of purple shines through the violet gloom
It is evident from this that the aster was recognizable and “not far to seek” indicating that they were easy to find. However, there is no evidence that asters played a significant role in Eurasian culture. There are a few tangential references to medicinal applications but no established pharmacopoeia; the English herbalist Thomas Culpepper recommended asters in the treatment of asthma and the Romans or Greeks used them in the treatment of snakebite, to frighten serpents – or perhaps both, the lack of clarity evidence of dubious etiology. The various allusions to the mythological provenance of asters are almost certainly fabrications. The most common stories are that asters resulted either when the goddess Virgo scattered stardust over the earth or when the goddess Astrea wept at being distraught by the wars of men. Virgo is the goddess of the autumn, evident in the zodiacal constellation’s rise in late August which would coincide with the florescence of asters – it would therefore be a logical assignment of the aster to the realm of the constellation Virgo. The association with Astrea, the ‘star-maiden’ is almost certainly due to an alliterative association with the root word for star. Asters were purportedly used in Chinese medicine for everything from hangover to hemorrhage.
From the North American perspective, asters played a much greater ethnobotanical role, likely a result of the ubiquity of asters and the herbal skills of the autochthonous peoples. Perhaps the most novel of these was as a lure to attract game; the Ojibwa or Chippewa, third largest tribe in North America with a Great Lakes nexus, employed the smoke from a variety of asters as a means of drawing deer close enough for a bow and arrow – the scent presumably a pheromone. The Meskwaki or Fox tribe of the upper Mississippi Valley used asters in an Inipi, or sweat lodge to drive away the bad spirits of illness, particularly those associated with mental disorders. The New England Aster stands apart as a medicinal that was not only widely used by Native Americans but also adopted by the early colonists. The primary Indian uses were as a febrifuge when made into a tea and as a salve against skin rashes when decocted or boiled. The colonists extended its use in employing vaporous steam inhalation as an aromatic nervine to reduce nervous anxiety. C. S. Rafinesque’s 1830 Medical Flora extolled the virtues of aster as a palliative for skin rashes caused by poison sumac and as a treatment to alleviate nervous disorders, “in many cases preferable to Valerian,” – valerian is a traditional herbal sedative dating to Ancient Greece. It has been generally reported that chewing aster flowers results in a peaceful state of mind that promotes calming.