Symphyotrichum boreale (formerly Aster borealis) is a species of flowering plant of the aster family (Asteraceae) native to North America. Commonly known as rush aster, northern bog aster, and slender white aster,[4] it is a perennial, herbaceous plant that may reach heights of 85 centimetres (2 feet 9 inches).
Description
Symphyotrichum boreale is a perennial, herbaceous plant that reaches between 13 centimetres (5 inches) and 85 cm (2 ft 9 in) high. The leaves, stem, and overall plant form are slender, and it produces long rhizomes. The inflorescence consists of one to several composite flowers. The ray florets are white to pale purple, and the disc florets are cream or pale yellow, becoming purplish.[4] The leaves are simple, with alternate or basal arrangement.[5]
Symphyotrichum boreale was formerly included in the large genus Aster as Aster borealis. However, this broad circumscription of Aster is polyphyletic and the North American asters are now mostly classified in Symphyotrichum and several other genera.[6]
Hybrids between this species and Symphyotrichum puniceum have been recorded and are called Symphyotrichum × longulum.[4]
Possible holotype of Aster longulus, basionym of hybrid Symphyotrichum × longulum