Poison Ivy - The Persisting UKtrees Tag

The tag UKtrees has mysteriously appeared on all posts about Ivy. I thought I had managed to remove
them all but one post is being particularly stubborn -

I have tried at least 3 times and Derek has tried too, but the tag persists.

Another mystery. I thought I would apply filter again to try to get rid of it, but no results appear for Hedera helix by wortmaggot
Oh well.

Stop Press : The problem has been solved by Mags.
I deleted UKtrees but at the same time replaced it with a different tag.
Thank you Mags

Well raised, thanks. That particular tag issue has been with us since the beginning and it has been noted before in a Forum Item.
Yes, it has a simple solution: add an innocent tag like urban or rural (FROM the tag list) then remove the stuck tag, This applies to ONLY a solitary tag you want to delete.
.
Please (everyone) consider using less tagging and only those which are Collection tags, like UKleaves and nothing that is implicit in the Observation, like Nottingham, green or bigmoth. Before INVENTING a tag please look first in the tag list and perhaps ‘ask around’
https://www.ispotnature.org/communities/uk-and-ireland/view/project/824066/

Don’t give up, Derek!