Tall 15-20metres.Trunk 3.5 -4 metres circumference
No interactions present.
Aspen leaves are almost circular, and look as though they have been cut out with a "cookie cutter" giving fluted edges.
These more triangular leaves look like Black Poplar, or more probably one of the hybrids.
The lack of a long point at the tip of the leaf would incline me towards Populus nigra x canadensis.
The "rustling" sound definitely puts it in the "poplar" category!
How to take close-ups with cheap phone and hand-lens:
Field Guides for Budding Botanists:
Lat/Lng: 51.5396, -3.4505
OS grid ref: SS994832