Home   Dicots   Another of those damned elusive yellow compositae!

Another of those damned elusive yellow compositae!

crepis slide

Dr M has already posted (here) on those conspicuous and characteristic yellow dandelion-like plants which we see all around, especially in grassland and on waste ground and which, despite their superficial resemblance to Dandelions (Taraxacum sp), actually include a number of related genera.

These plants  can pose ID problems, especially for the beginning botanist, who might ponder upon the featured image at the top of this post thus:

“Hmmmm it’s a dandelion! No, maybe a Sow Thistle?  Perhaps a Hawkbit?  Or do I mean a Hawk’s-beard? Oh no! is it a Cat’s-ear? Arrrgh! Perish the thought, could it be one of those damned elusive Hawkweeds?!”

Recently, Dr M has noticed this rather robust and splendid yellow composite in rough grassy areas on the campus of the University of Reading as well as on roadsides, motorway verges etc.

Now, this is not one of those keep you guessing posts, Dr M is keen to encourage you in your growing affection for this group (and just in case you weren’t sure, yes you do have a growing affection for the yellow composites, oh yes you do! OK, I let’s not argue, just read on!).

So, no beating about the bush or even the yellow composites here, the genus is Crepis (The Hawk’s-beards) which is covered in Dr M’s earlier post but is a different species, so let’s have a closer look:

Crepis vesicaria trio

The Hawk’s-beards (Crepis species): characterised by usually leafy branched stems, with latex, phyllaries (receptacular bracts) in 2 rows, the inner in one erect equal row (unlike the other yellow composites where they are often unequal and overlapping), the pappus is white with simple hairs (i.e. not feathery), the capitulum has ligule florets only and they are yellow, the achenes are not flattened (as they are in e.g. Sonchus, the Sow-thistles), and are ribbed or long-beaked or at least slightly tapered at the apex.

This species is Crepis vesicaria (Beaked Hawk’s-beard), an erect hairy perennial, with stem leaves deeply and sharply lobed and clasping the stem at their base, the phyllaries have glandular and non-glandular hairs, the achenes are 5-9 mm long with a long narrowing section (a beak).  This is an introduced species and naturalised widely in grassy places and waste ground, especially in the south of Britain and flowers May -July

Here is some further useful info gleaned from the veg key:

Perennial herb, 1-several stems, ridged and purplish below roughly hairy or with black bristles, hairy with septate hairs, the petiole is solid and often purplish near the base, with red-based hairs, at least near midrib above, with bitter bluish white latex (not turning brown in time), leaves with large terminal lobe, and sharply toothed lobes, stem leaves clasping the stem.

So, next time you see one of these yellow composites don’t curse them and cross the road (or field, or road verge) as fast as your legs will carry you, instead embrace them and admire them and even ID them!

Examine their vegetative structures, their stems and leaves, and their little composite bits and pieces, and use the veg key and the wild flower guides and the book of Stace to broaden your experience, knowledge and appreciation of this common, ubiquitous and beautiful group!

Dr M’s tangential left-of-field footnote #42:

Paraphrasing the Famous 5: “Come along you eXtreme botanists, let’s go for a walk in the countryside and seek out lashings of yellow composites, Hurrah!”

Literary footnote: Lashings of Enid Blyton – Actually she never wrote the line “lashings of ginger beer” in any of the famous five books or any other book for that matter, check it out here.

 

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