OK I am in the UK,
Planted by old neighbours possibly about 10 years ago - approx 6-7 m tall
Currently shedding hundreds of dandelion type seeds from its green coloured catkins - last year was the first time it did this and the garden looked like it was covered in cotton wool.
I think its deciduous
The leaves are small oval pale/mid green colour.
Trunk is solid at the bottom breaking into lots of smaller branches which sway a lot in the wind. Branches/trunk itself are greenish grey.
Desperately need to identify it as its now above fascia level on the house and is only (max) 2 m from our house.
I have photographed it & will try to put on profile if needed!!