CANADIAN GOLDENROD

Solidago canadensis

Daisy & Dandelion Family [Asteraceae]

Flowers:
month8jul month8july month8aug month8sep month8sept

Pappus: pappusZpossible (white)
pappus8sep pappus8sept pappus8oct

status
statusZneophyte
 
flower
flower8yellow
 
morph
morph8actino
 
petals
petalsZ8
(7-11)
type
typeZclustered
 
type
typeZpanicle
 
stem
stem8round
 
toxicity
toxicityZmedium
 

16th Aug 2010, dunes, Southport, Sefton Coast. Photo: © RWD
Up to 1.3m tall.


16th Aug 2010, dunes, Southport, Sefton Coast. Photo: © RWD
Forms large patches of clones by vigorously spreading rhizomes (thick underground horizontal roots). Here mingling with a whitish-green low Willow plant.


30th Aug 2010, Nob End SSSI, Clammerclough, Lancs. Photo: © RWD
Pyramidal-shaped inflorescences.




16th Aug 2010, dunes, Southport, Sefton Coast. Photo: © RWD
Inflorescent panicles curve over to almost horizontal.


27th July 2007, Freshfield, Sefton Coast. Photo: © RWD
The individual flowers emerge from the curving stem on short stalks which twist around so that each flower sits on the top of the stem. This arrangement is called 'secund'.


27th July 2007, Freshfield, Sefton Coast. Photo: © RWD
The yellow flowers emerge from a light green involucre consisting of several overlapping phyllaries.


27th July 2007, Freshfield, Sefton Coast. Photo: © RWD
The few disc florets stick out above the ring of ray florets, which are also few in number. The light-green phyllaries are of various lengths.


27th July 2007, Freshfield, Sefton Coast. Photo: © RWD
The ray florets number about 7-11


16th Aug 2010, dunes, Southport, Sefton Coast. Photo: © RWD
Opened disc florets have orange-yellow stamens emerging.


30th Aug 2010, Nob End SSSI, Clammerclough, Lancs. Photo: © RWD
The tip of the inflorescence - in these specimens from Nob End the ray florets are shorter.


16th Aug 2010, dunes, Southport, Sefton Coast. Photo: © RWD
Un-opened disc florets resemble tiny eggs, their number varying from 2 to 6. Ray florets are slightly more numerous. Tiny yellow bifurcating stigmas can be seen in the central lower flower.


16th Aug 2010, dunes, Southport, Sefton Coast. Photo: © RWD
Leaves taper at both the base and the tip and have three prominent veins.


30th Aug 2010, Nob End SSSI, Clammerclough, Lancs. Photo: © RWD
The radially displayed leaves from above on a short and young specimen.


16th Aug 2010, dunes, Southport, Sefton Coast. Photo: © RWD
The leaves have a few well-separated prominent forwardly-directed teeth, and are slightly whitish green because of short hairs, which may be absent in places.


30th Aug 2010, Nob End SSSI, Clammerclough, Lancs. Photo: © RWD
The upper portion of the stem has hairs (short ones), but not the lower half.


Not to be semantically confused with : Canadian Fleabane (Erigeron bonariensis) [a plant of similar name belonging to the same family but differing Genera] nor to Canadian Waterweed (Elodea canadensis).

Easily mistaken for : garden varieties of Canadian Goldenrod.

Easily mis-identified as :

  • Early Goldenrod (Solidago gigantea) is usually taller at up to 2.5m (but can be as short as 0.5m) and has more or less hairless leaves except sometimes on the veins underneath the leaf, and it has between 6 and 10 (12) disc florets whereas Canadian Goldenrod has between only 2 to 8.
  • Rough-stemmed Goldenrod (Solidago rugosa) which has between 3 and 8 disc florets and presumably a rough stem, but it does not occur on the Sefton Coast.

Hybridizes with : Goldenrod (Solidago virgaurea) to produce the sterile Silidago × niederederi but that appears to be extinct not seen since 1999 and even then only in four hectads nowhere near the Sefton Coast.

There are two sub-species with only slight variations between them:

  • (Solidago canadensis ssp. canadensis)
  • (Solidago canadensis ssp. altissima)
The sub-species of Canadian Goldenrods from North American are numerous and difficult to differentiate between, and may, or may not have given rise to the British sub-species with some possibly being cultivars or hybrids that have arisen in the UK, particularly in regard to Early Goldenrod and Rough-stemmed Goldenrod.

Disc florets number between 2 and 8 (whereas Early Goldenrod has between 6 and 10 (12) disc florets, so it cannot be that).

Grass-leaved Goldenrod (Solidago graminifolia) is more like Goldenrod with just a single spike of flowers which is flat-topped but it has much narrower leaves than does Goldenrod.

Inhabits waysides and waste ground, spreading in great clones by underground rhizomes. Only one or two specimens were recorded at Nob End in 1978, but by 2010 the population had covered several dozen square metres.

Three colours of dye, mustard, orange and brown, can be extracted from the whole plant.

It is poisonous containing some pyrrolizidine alkaloids,


  Solidago canadensis  ⇐ Global Aspect ⇒ Asteraceae  

Distribution
 family8Daisy & Dandelion family8Asteraceae

 BSBI maps
genus8Solidago
Solidago
(Goldenrods)

CANADIAN GOLDENROD

Solidago canadensis

Daisy & Dandelion Family [Asteraceae]