Confounded Composites

Dandelion ... or Sowthistle?

Dandelions ... or Hawkweed?

Q.When doesn't a dandelion-like  flowerhead belong to a dandelion?

A.When it belongs to a

• Cat's Ear
• Sowthistle
• Hawkweed
• Hawk's Beard
• Hawkbit 
• Lettuce
• Nipplewort
• Goat's Beard
• Oxtongue
• Viper's Grass
• Colt's Foot

with multiple variations possible amongst these categories.  

I came across a yellow dandelion-like flower growing in my back garden several weeks ago and have been trying to narrow down which one it is ever since.  It has been driving me mad. 

Here are some of the features I have learnt are relevant to correct identification:

Time of flowering
Location
Habitat
Height
Stem - Hollow or not,secreting lactose or not,branched or unbranched,leafy or bare, green or purple, ribbed or not, prickly/hairy/bracted
Leaves - Shape/how attached
Rosette - The shape of the overwintering leaves at ground level
Flower - size, depth of colour, construction, 
Flowerheads - bunched or single/bracted or not/bract patterns
Fruiting head and Pappus (dandelion clock)

I tried to reduce these key features but it turns out that there is always another species whose tell tale characteristic is something you hadn't thought of. Here is my seemingly innocent candidate. It cropped up in the lawn and also in the wildflower bed.  Multiply branched at ground level and up the stems I would describe it as wirey stemmed (not round or hollow). 

The profile view is more telling because it reveals there are two sets of bracts one long and the other short (sepal like). 

 That makes it a Hawk's-beard. The Crepis family comprises some 200 siblings worldwide. 17 are said to be  native to the UK,  The most frequently found here are:

Crepis capillaris    Smooth Hawksbeard
Crepis vesicaria    Beaked Hawksbeard
Crepis biennis        Rough Hawksbeard

.

But searching for a basal rosette I am thwarted as there is only the remnants if there was one at all. 

The stem leaves are however making the case for Crepis capillaris  Smooth Hawk's-beard.

Here is the full SP on Crepis capillaris:

Introduced, warm season, annual or short-lived perennial herb to 75 cm tall. Stems are branched, with sparse, crinkly hairs. Basal leaves form a rosette, and are oblanceolate to lanceolate in outline, 10–25 cm long, 1–5 cm wide, margins toothed to runcinate-pinnatifid, glabrous or ± hairy. Cauline leaves are smaller, mostly narrow-lanceolate, stem-clasping, with acuminate auricles. Heads are 5–6 mm diam., and numerous, on slender peduncles, in loose corymbose panicles; involucral bracts are lanceolate, with sparse to dense white non-glandular and dark glandular hairs. Florets are all ligulate, the corolla yellow, often with pink or red stipe on outer face of ligule. Achenes are 2 mm long, lack a beak and have a pappus of simple white hairs. Flowering is in summer. A native of Europe, it is a weed of roadsides and disturbed areas.

So that's pretty clear?

This description along with the photo below have convinced me,

Source :

https://www.flickr.com/photos/macleaygrassman/15900577274/in/photostream/

At least I can say with confidence that this is a dandelion...

....cant I?