Hi please help we have started to find these growing in different places around our vegetable patch, we have poisoned a few coming from the neighbours fence and check against the on line pictures for knotweed but find nothing that resembles them, so hoping not, anyway any advice how to deal with this problem would be greatly appreciated
regards Gordon Steve

Welcome to the site!

Looks like it could be Erigeron canadensis, Horseweed.

Horsetail - Equisetum

Equisetum arvense, one of the most primitive plants. Pretty much impossible to eradicate.

That was my first thought too.
Here is our database entry to see all the images and scroll down for member comments.

Field Horsetail (Equisetum arvense)

This illustration from that database, matches the piece on the left of your photo. Click to enlarge.

It's very common in the UK. The roots can go down 6 feet I believe. I doubt it would have any negative effect on any crops in the allotment.

Thanks all for your thoughts we are very grateful for your advice, looks like we have a bit of a fight on our hands to control this

misticunicorn said: Thanks all for your thoughts we are very grateful for your advice, looks like we have a bit of a fight on our hands to control this

We had it in our old garden in South Wales UK.
Tried every way from digging really deeply to chemicals...nothing worked.
Impossible to get rid of it.
You just have to learn to live with it.

Only sure way to escape it, is to move house!

Much like nut grass

misticunicorn said: Thanks all for your thoughts we are very grateful for your advice, looks like we have a bit of a fight on our hands to control this

Learn to live with it, it's not harmful and shouldn't affect your crops.