Is this a Black Poplar?

[Chris]

I think it is from the leaves, but I have not noticed one in the wild before so thought I’d double check. This was in Lincolnshire.

 

[Pattree]

My immediate reaction was - yes. There are many escapes in UK.

A silhouette could be useful.

On a closer look at your photo I still think so but they hybridise very easily. I would have expected alternate veining where the leaves in your post look opposite.
So my answer is “probably”.

 

[TLM]

I would have expected alternate veining where the leaves in your post look opposite.

That seems to depend on which leave one is looking.