Yellow Thistle name please

[alindsay]

Is this a type of Sowthistle?

Note the white veining on the leaves.

[Johnny81]

Prickly Sow-thistle Sonchus asper.

[alindsay]

Thanks Johnny

[leifus]

Originally Posted by Johnny81

Prickly Sow-thistle Sonchus asper.

yep!

ID tip to distinguish between prickly and perennial sow-thistle:

look for glandular hairs on the calyx (easiest when they're in bud as you can see at the top in the middle of your photo). If they're pale yellow then it's Perennial sow-thistle. If they're either absent or black then it's sonchus asper

[alindsay]

Leifus

Any tips on the difference between prickly and smooth sowthistle?

Thanks in advance

[leifus]

Originally Posted by alindsay

Leifus

Any tips on the difference between prickly and smooth sowthistle?

Thanks in advance

it's usually fairly easy to tell just by looking at how prickly the leaves are.

For example very prickly leaves like this:



suggest prickly sow-thistle

but leaves that are much less prickly and usually a duller green like these:



suggest smooth sow-thistle.

This is by no means definite, as prickly sow-thistle can have suprisingly smooth leaves, but it's a fairly good guide

if you want a more complicated wordy way of distinction, look at the auricles on the stem leaves. In Prickly the auricles are pointed and spreading. In smooth, they are spiny and rounded.

Also, in prickly the achenes (single-seeded fruit) are wrinkled between the ribs, whereas in Smooth, they are smooth between the ribs.


Hope that helps a little, if you can make sense of my explanation, which isn't very clear, sorry

[King Edward]

Originally Posted by leifus

if you want a more complicated wordy way of distinction, look at the auricles on the stem leaves. In Prickly the auricles are pointed and spreading. In smooth, they are spiny and rounded.

This should be the other way round:
Pointed auricles = Smooth
Spiny, rounded auricles = Prickly

N.B. Auricles are the parts at the base of the leaf that project backwards, behind or wrapping round the stem.

[alindsay]

I think I've got it .......

Thanks all. A valuable tutorial.

[Johnny81]

If you ever get to go to the East Anglian fens you will probably see Marsh sow thistle too, this is unmistakable as it grows really tall!!!

[stevecurtis]

Great info,thank you.

all the best steve