Salix Alba is a weeping Willow.

I am sorry to differ with you Betsy, but Salix alba is not a Weeping Willow which is Salix × sepulcralis
Salix alba:
https://www.google.be/imgres?i...
and Salix × sepulcralis
https://www.google.be/search?q...

Hard to know... Pictures are showing it both ways all over the Internet.

It's not completely erect though.

Salix alba 'Tristis' is a cultivar, my tree picture was taken in a nature reserve.

Your right then.

Delete this thread. I'm wrong.

I cannot delete the thread Betsy, only an admin. can do that.
But I do not see the need, it is good to be critical!

Trista is not in the data base so I assumed Trista was Alba.

Salix alba 'Tristis' is a synonym of Salix x sepulcralis var. chrysocoma.
It is in the database:
Golden Weeping Willow (Salix x sepulcralis)