Downy?

Downy?

Observation - Downy?. Description: Growing from a retaining wall below wooded railway line. Originally mistook for Black Poplar but these deltoid leaves are doubly serrate. Nearest I can get is Downy Birch, but lacking in downyness.

Growing from a retaining wall below wooded railway line. Originally mistook for Black Poplar but these deltoid leaves are doubly serrate. Nearest I can get is Downy Birch, but lacking in downyness.