In the William Turner garden
This page simply reformats the Flickr public Atom feed for purposes of finding inspiration through random exploration. These images are not being copied or stored in any way by this website, nor are any links to them or any metadata about them. All images are © their owners unless otherwise specified.
This site is a busybee project and is supported by the generosity of viewers like you.
In the William Turner garden
Symphyotrichum is a genus of over 100 species and naturally occurring hybrids of herbaceous annual and perennial plants in the composite family, Asteraceae, most which were formerly treated within the genus Aster. The majority are endemic to North America, but several also occur in the West Indies, Central and South America, as well as one species in eastern Eurasia. Several species have been introduced to Europe as garden specimens, most notably New England aster (Symphyotrichum novae-angliae) and New York aster (Symphyotrichum novi-belgii).
Description
Taxonomy of Symphyotrichum is difficult. Species are usually heterophyllous, some strongly so. Individuals in the spring, with basal rosettes, often have leaf shapes quite different from those with cauline leaves seen later in the season. Phyllary shape on first- and later-formed heads may differ. Individuals may vary considerably in plant size and array development depending upon growing conditions. The genetic diversity within each species also appears considerable.
For all species in the genus, the ray florets are white, pink, blue, or purple. Disc florets are yellow to white, becoming pinkish, reddish purple, or brown when mature. There are 5 lobes on the disc florets of all species in the genus.
Taxonomy
German botanist Christian Gottfried Daniel Nees von Esenbeck established this genus in 1833 because he thought that a plant he examined, now believed to be a cultivated variety of New York aster (Symphyotrichum novi-belgii), which he called Symphyotrichum unctuosum, was sufficiently distinct from the rest of the genus Aster to warrant its own genus. Nees emphasized the uniqueness of this plant in having its pappus hairs arranged in a coherent, basal ring. This structure is the basis for the scientific name of this genus, which derives from Ancient Greek σύμφυσις (sýmphysis) "growing together" and θρίξ (thríks; stem τριχ- trich-) "hair". However, this characteristic ring is not generally shared by most New York aster pappi, nor is it characteristic of any other plants included in the modern concept of Symphyotrichum. Regardless, according to the rules of the International Code of Nomenclature for algae, fungi, and plants (ICN), the timing of the genus' establishment gives it precedence over other names. The genus was resurrected in 1994 by American botanist Guy L. Nesom to group together species formerly included in the genus Aster in order to make modern genera monophyletic.
Subdivisions
Symphyotrichum has been divided into five subgenera:
Subgenus Ascendentes
This subgenus includes two species from the western United States and Canada that originated as hybrids between species in the subgenera Symphyotrichum and Virgulus.
Subgenus Astropolium
This subgenus includes about 10 species found across the Americas in salt marshes and salt flats.
Subgenus Chapmaniana
This subgenus includes a single species, S. chapmanii, found in Alabama and Florida.
Subgenus Symphyotrichum
This subgenus includes about 65 species occurring across North America, including a few species in Central America and the Caribbean, with one species also occurring in Eurasia.
Subgenus Virgulus
This subgenus includes about 28 species occurring across North America, including a few species in Central America and the Caribbean.
Distribution
As a whole, Symphyotrichum is native throughout the Americas, with one species, S. ciliatum, also native to eastern Eurasia. Several species have been introduced to Europe and other parts of the world. Most species are native to Mexico, the United States, and Canada, with several species occurring in the West Indies and Central America. Most members of subgenus Astropolium are restricted to South America.
Species
As of June 2021, Catalogue of Life listed 106 accepted species and identified naturally-occurring hybrids, including the following:
Symphyotrichum ascendens (Lindl.) G.L.Nesom – western aster, longleaf aster, intermountain aster
Symphyotrichum campestre (Nutt.) G.L.Nesom – western meadow aster
Symphyotrichum chilense (Nees) G.L.Nesom – Pacific aster, common California aster
Symphyotrichum cordifolium (L.) G.L.Nesom – heartleaf aster, common blue wood aster
Symphyotrichum defoliatum (Parish) G.L.Nesom – San Bernardino aster
Symphyotrichum depauperatum (Fernald) G.L.Nesom – serpentine aster
Symphyotrichum dumosum (L.) G.L.Nesom – bushy aster, rice-button aster,
Symphyotrichum eatonii (A.Gray) G.L.Nesom – Eaton's aster
Symphyotrichum ericoides (L.) G.L.Nesom – white aster, heath aster
Symphyotrichum falcatum (Lindl.) G.L.Nesom – white prairie aster, falcate aster, western heath aster
Symphyotrichum frondosum (Nutt.) G.L.Nesom – short-rayed alkali aster
Symphyotrichum georgianum (Alexander) G.L.Nesom – Georgia aster
Symphyotrichum greatae (Parish) G.L.Nesom – Greata's aster
Symphyotrichum hallii (A.Gray) G.L.Nesom – Hall's aster
Symphyotrichum laeve (L.) Á.Löve & D.Löve – smooth aster, smooth leaved aster, glaucous aster
Symphyotrichum lanceolatum (Willd.) G.L.Nesom – panicled aster, tall white aster
Symphyotrichum lateriflorum (L.) Á.Löve & D.Löve – calico aster
Symphyotrichum lentum (Greene) G.L.Nesom – Suisun Marsh aster
Symphyotrichum novae-angliae (L.) G.L.Nesom – New England aster
Symphyotrichum novi-belgii (L.) G.L.Nesom – New York aster
Symphyotrichum oblongifolium (Nutt.) G.L.Nesom – aromatic aster
Symphyotrichum oolentangiense (Riddell) G.L.Nesom – sky-blue aster, azure aster
Symphyotrichum pilosum (Willd.) G.L.Nesom – hairy aster, frost aster
Symphyotrichum prenanthoides (Muhl. ex Willd.) G.L.Nesom – crooked-stem aster
Symphyotrichum puniceum (L.) Á.Löve & D.Löve – purplestem aster, red-stemmed aster, swamp aster
Symphyotrichum sericeum (Vent.) G.L.Nesom – western silver aster, silky aster
Symphyotrichum shortii (Lindl.) G.L.Nesom – Short's aster
Symphyotrichum subulatum (Michx.) G.L.Nesom – eastern annual saltmarsh aster
Reproduction
Ray florets in the Symphyotrichum genus are exclusively female, each having a pistil (with style, stigma, and ovary) but no stamen. Ray florets accept pollen and each can develop a seed, but they produce no pollen.
Each ray floret has a strap-shaped corolla (or ligule) formed from three vestigial petals which are fused together. The floret contains one inferior ovary, and this ovary contains one ovule.[a] The ovary has an attached style that extends outward from between the ray floret corolla and the rest of the flower head. As the ray floret is blooming, the stigma at the top of the style splits into two lobes.
Disk florets in the Symphyotrichum genus are androgynous, each with both male (stamen, anthers, and filaments) and female reproductive parts; thus, a disk floret produces pollen and can develop a seed. The disk floret has five petals, sometimes referred to as lobes, which are fused into its own corolla in the shape of a tube.
The male stamen is inside the tube-shaped corolla of the disk floret. It has five anthers, five filaments, and produces pollen. The anthers and filaments are readily visible as separate entities in non-Asteraceae species. Here, they are fused together to form a cylinder, or tube, with their pollen on the inside only. This male anther cylinder surrounds the female style and stigma. As the style is maturing, it elongates up through the anther cylinder, gathering the pollen on its stigma along the way.
The ovary is at the bottom of the disk floret style. As with the ray floret, the disk floret stigma has two lobes that are fused together. The disk floret's stigma stays closed while pollen is on it, keeping its ovary safe from self-pollination. After the pollen has been collected and carried off by one or more pollinators, the stigma begins to split into two lobes, opening the style so that the disk floret ovary becomes accessible to receive pollen from another plant.
Colias philodice
These are either New York or San Bernadino Asters. I was attracted to their yellow & speckles of orange in the disc floret plus the lavender to darker purple ray florets.
I continue to dabble with colors & light balance for my winter challenge; as each day passes, Spring is that much closer!
9900
In bloom near high water mark, E shore Houghton's Pond, Blue Hills Reservation, Milton, MA 10/17/24
