
The Black Poplar (Populus nigra var betulifolia) is one of Britain’s most endangered native timber trees. There are only 3000 specimens, of which just 600 are female.
The Black Poplar was once a common sight in Britain. It was a very useful source of timber and was often planted near farms and villages and used for scaffolding, wagon making, even for arrows - a Black Poplar in Portsmouth is the descendant of one used to make arrows for the armoury of the Mary Rose.

However, the Black Poplar needs very specialised conditions in which to propagate. The seeds need to lie undisturbed on bare, wet mud or silt from June to October to germinate successfully. These conditions became harder to find as suitable habitats were lost.

Also as the need for native timber dwindled fewer Black Poplars were planted, this propagation difficulty became more important. Even worse, as a rule only male trees were planted: the females were considered a nuisance because of the drifting white down they produce.
thanks to Peter Roe’s informative
Black Poplar website for this information.

It is nice to know that a local nature reserve,
the Chase has six female specimens. These photographs were taken here earlier today.
London Wildlife Trust