Old Field Asters and Relatives
Symphyotrichum subsect. Porteriani includes five x=8 species of asters native to North America. Four are native to the eastern United States and adjacent Canada (1 sp.) and one is native to the foothills of the Front Range of the Rocky Mountains. All five species have phyllaries with inrolled margins near the apex (this makes the phyllaries look spinulose) and basal rosettes that form in the late summer and fall. The cytogeography of S. pilosum and relatives was discussed in Semple (1978), Semple and Chmielewski (1985) and Chmielewski and Semple and (1989).
Symphyotrichum pilosum was erroneously treated as Aster ericoides in the last century and given the common name of "Heath Aster" which has persisted in the nursery trade and floras even though the name should apply to the the virguloid aster Symphyotrichum ericoides shown below, which has truly spinulose phyllaries.
The common name "Old Field Aster" is more appropriate for S. pilosum. "Pringle's Aster" S. pilosum var. pringlei is also sold at nurseries.
The five species of subsect. Porteriani are included in Brouillet et al. (2006 FNA):
- Symphyotrichum depauperatum
- Symphyotrichum parviceps
- Symphyotrichum pilosum
- Symphyotrichum porteri
- Symphyotrichum priceae
Semple, J.C. 1978. The cytogeography of Aster pilosus (Compositae): Ontario and the adjacent United States. Can. J. Bot. 56: 1274-1279.
Semple, J.C., and J.G. Chmielewski. 1985. The cytogeography of Aster pilosus (Compositae-Astereae). II. Survey of the range, with notes on A. depauperatus, A. parviceps and A. porteri. Rhodora 87: 367-379.
Chmielewski, J.G., and J.C. Semple. 1989. The cytogeography of Aster pilosus var. pilosus in southern Ontario revisited. (Compositae: Astereae). Can. J. Bot. 68: 3517-3519.
Last updated 30 January 2014 by J.C. Semple
© 2014 J.C. Semple, including all photographs unless otherwise indicated