New York Natural Heritage Program
Sky-blue Aster
Symphyotrichum oolentangiense (Riddell) Nesom
Kimberly J. Smith
Family: Aster Family (Asteraceae)

State Protection: Endangered
listed species are those with: 1) 5 or fewer extant sites, or 2) fewer than 1,000 individuals, or 3) restricted to fewer than 4 U.S.G.S. 7 minute topographical maps, or 4) species listed as endangered by U.S. Department of Interior.

Federal Protection: Not Listed

State Rarity Rank: S1
A State Rarity Rank of S1 means: This plant is endangered/critically imperiled in New York because of extreme rarity (typically 5 or fewer populations or very few remaining individuals) or is extremely vulnerable to extirpation from New York due to biological factors.

Global Rarity Rank: G5
A Global Rarity Rank of G5 means: This species is demonstrably secure globally, though it may be quite rare in parts of its range, especially at the periphery.

Did you know?
This beautiful aster was originally described in 1835 by botanist John Leonard Riddell and named Aster oolentangiensis after the Olentangy River in Ohio where he found it near Worthington, Ohio. Riddell misspelled the river name with two Os and thus the species has that spelling. Its name was later changed to Aster azureus to reflect its sky blue flower color. When the genus was changed to Symphyotrichum the older species name had precedence.

State Ranking Justification [-]
There is one large existing population with hundreds of plants and another population with just one plant which is probably extirpated. There are three historical occurrences from 1888 to 1936 but they are also probably extirpated.

Short-term Trends [-]

Long-term Trends [-]