Can anyone identify this weed - it's everywhere?

[George the Pigman]

This year my allotment has been swamped by a weed that I can't identify despite having a book on the subject! It has been on the plot before but never in such numbers. Its very low and spready, hugging the ground and fairly easy to pull out.
Photo attached

[George the Pigman]

[Deb P]

Chamomile?

[gray1720]

It's something in that postcode, anyway. Does it smell strongly? If so, it could be stinking mayweed? Some people think it smells vaguely like pineapple...

[George the Pigman]

Smells of nothing at all even when crushed.

[gray1720]

Not that then!

[ancellsfarmer]

So is it "
Tripleurospermum inodorum - Scentless Mayweed " ?
https://www.first-nature.com/flowers/tripleurospermum-inodorum.php

[George the Pigman]

No it's flat as a pancake on the ground . It sprawls in a roughly star shaped pattern never rising more than a millimetre or two from the ground. Perhaps I have a rarity for the National Collection of weeds!

[Vinlander]

This is interesting to say the least...

I have something on my plot (it loves my polytunnel) that looks very like your photos - lots of plants have leaves like that and a prostrate sprawl, but the arrangement of the flower buds/fruits is identical to your photo.

I would normally regard this as conclusive, but mine has a fairly pungent smell and a delicious rich "warm" taste somewhere between cress and rocket - but only in tiny quantities because otherwise the bitterness swamps everything else.

If anyone finds it I recommend you try a tiny leaf before you destroy something that could be as important as rocket in your kitchen.

I tentatively identified it as a Lepidium -  probably L.didymum - lesser swine cress, which is closely related to the "greek cress" that appears in many seed catalogues. I assume pigs like it - I do!

There are photos very like yours on https://www.naturespot.org.uk/species/lesser-swine-cress with closeups of the flower buds/fruits. It's difficult to see that stuff on your photo - whether your flower stems show buds or fruits - even more difficult to distinguish the double fruits but I think there is a related species that has singles - or at least looks more like singles.

It's may be that a slightly different species has no smell or flavour. Please ask a friend or neighbour to try a tiny leaf, because...  I don't want to sound rude, but it's also possible (in these dark days) that you have recently recovered from Covid19. There is also a massive genetic variation in this area - I remember this demonstrated in a science lesson by a substance that only half the class could taste at all.

Cheers.

[George the Pigman]

Vinlander -you've cracked it! It must be swine cress. It fits with my soil type-clay. Apparently it was originally introduced as a herb back in the 18th Century. I will investigate its odour and taste when I am next at the allotment. I could have been discarding and important crop!

[Vinlander]

It must be swine cress. I will investigate its odour and taste when I am next at the allotment. I could have been discarding and important crop!

Hi George - I'd be interested in your opinion of the flavour, because if I'm really right about it, it will be hard to miss - though you'd have to be a BIG fan of rocket to really enjoy it. OTOH if it has no warm flavour, have you tried it on anyone else?

As you can tell I'm a big fan of big flavours - & almost evangelical about new ones (not to mention my crusade against blandness). I suppose this herb qualifies as picking up an unconsidered trifle (not to be confused with Eton mess ).

Cheers.