Asters

Asters and other Compositae

The Coldens reached their limit as taxonomists when it came to identifying the Asters (Aster spp. and allies).   According to the USDA site on New York flora, there were 28 species of Asters and other Aster-like composites that could have been noticed by Jane or Cadwallader during their years of plant study.  These are listed at the end of this review.  Jane identified 4 species of plants she referred to as “Aster” species, Cadwallader identified 6 in his Plantae Coldenghamiae.  

What made the Asters difficult to identify was the flowerform, which seemed very similar across a broad spectrum of plants within the Composite family.  The traditional disk-ray display of the flowerhead (essentially a structure consisting hundreds if not thousands of small flowers known as florets), included the sterile “petaliform” ray florets which were sterile usually and served mostly as attractants for pollinators, and the very fertile monotonous disk flowers in the middle disk to cylindrical portion of the flowerhead.  Each floret consists of five petals fused to form a tube-like structure, so small it is barely visible as a fused structure in the smallest flowering species. 

This disk-ray form of the Coldens’ “Asters” differs greatly from the uniform florets displayed by the other half of the Aster or Composite family.  These equally common species such as dandelion, thistle, burdock and hieracium posed less of a problem for Jane and Cadwallader during their attempts to identify any newly found species.  For this reason, it is possible that some of the Coldens’ “Asters” weren’t even Asters at all, or even the most similar looking Aster-like relatives identified by the US Department of Agriculture in its review of New York plants.

The following photos of possible “Asters” are provided for comparison with Jane’s and Cadwallader’s notes on their appearances.   Those most likely related to Jane or Cadwallader’s description(s) are so noted.

New York Aster

Erigeron strigosis–White-top Fleabane

The Coldens were able to distinguish the following Aster-like flowers:

Bellis perennis L. (Lawn Daisy)

.

USDA list of “Asters” Common to New York

  • 1–Aster chinensis L. – Callistephus chinensis (L.) Nees (china aster) [Introduced]
  • 2–Aster divaricatus L. – Eurybia divaricata (L.) G.L. Nesom (white wood aster) [Native]
  • 3–Aster macrophyllus L. – Eurybia macrophylla (L.) Cass. (big-leaf aster) [N]
  • 4–Aster linariifolius L. – Ionactis linariifolius (L.) Greene (flaxleaf whitetop aster) [N]
  • 5–Conyza asteroides L. – Sericocarpus asteroides (L.) Britton, Sterns & Poggenb. (toothed whitetop aster) [N]
  • 6–Conyza linifolia L. – Sericocarpus linifolius (L.) Britton, Sterns & Poggenb. (narrowleaf whitetop aster) [N]
  • 7–Aster concolor L. – Symphyotrichum concolor (L.) G.L. Nesom (eastern silver aster) [N]
  • 8–Aster cordifolius L. – Symphyotrichum cordifolium (L.) G.L. Nesom (common blue wood aster) [N]
  • 9–Symphyotrichum lowrieanum (Porter) G.L. Nesom (Lowrie’s blue wood aster, syn. Aster cordifolius L. var. laevigatus Porter)
  • 10–Aster dumosus L via Aster dumosus L. var. dodgei Fernald – Symphyotrichum dumosum (L.) G.L. Nesom var. strictior (Torr. & A. Gray) G.L. Nesom (rice button aster) [N]
  • 11–Aster ericoids L – Symphyotrichum ericoides (L.) G.L. Nesom var. ericoides (white heath aster) [N]
  • 12–Aster laevis L – Symphyotrichum laeve (L.) A. Löve & D. Löve var. laeve (smooth blue aster) [N] 
  • 13–Symphyotrichum laeve (L.) A. Löve & D. Löve var. concinnum (Willd.) G.L. Nesom or Aster laevis L. var. concinnus (Willd.) House)
  • 14–variety of Aster tenuifolius L. = Aster tenuifolius L. var. ramosissimus Torr. & A. Gray  – Symphyotrichum lanceolatum (Willd.) G.L. Nesom ssp. lanceolatum var. lanceolatum (white panicle aster) [N]
  • four Aster lateriflorus L. (calico aster) varieties
  • 15–Symphyotrichum lateriflorum (L.) A. Löve & D. Löve var. angustifolium (Wiegand) G.L. Nesom
  • 16–Symphyotrichum lateriflorum (L.) A. Löve & D. Löve var. horizontale (Desf.) G.L. Nesom,
  • 17–Symphyotrichum lateriflorum (L.) A. Löve & D. Löve var. lateriflorum
  • 18–Symphyotrichum lateriflorum (L.) A. Löve & D. Löve var. tenuipes (Wiegand) G.L. Nesom (all named calico aster)
  • 19–Aster novae-angliae L. – Symphyotrichum novae-angliae (L.) G.L. Nesom (New England aster) [N]
  • 20–Aster novi-belgii L. – Symphyotrichum novi-belgii (L.) G.L. Nesom var. novi-belgii (New Belgium/New York Aster)
  • 21–Symphyotrichum novi-belgii (L.) G.L. Nesom var. elodes (Torr. & A. Gray) G.L. Nesom [N]
  • 22–Symphyotrichum novi-belgii (L.) G.L. Nesom var. villicaule (A. Gray) J. Labrecque & L. Brouillet [N, note Nova-belgii suggests local heritage]
  • 23–Aster puniceus L. – Symphyotrichum puniceum (L.) A. Löve & D. Löve var. puniceum (purple stem aster) [N]
  • 24–Aster tenuifolius L. – Symphyotrichum tenuifolium (L.) G.L. Nesom (perennial shoreline aster, rule out based on ecosystem) [N],
  • 25–Aster tradescantii L. – Symphyotrichum tradescantii (L.) G.L. Nesom (shore aster) [N, rule out based on ecosystem]
  • 26–Aster undulatus L. – Symphyotrichum undulatum (L.) G.L. Nesom (wavyleaf aster) [N]
  • 27–Aster tripolium L. – Tripolium pannonicum (Jacq.) Dobrocz. (sea aster) [N, rule out based on oceanside ecology].