Populus nigra ssp betulifolia is found throughout France and up through northern Europe to Denmark. After the last ice age as tree cover returned the British Isles were still part of the continent and therefore the poplar would have been present throughout. Only when the melt water from the North Sea flooded Doggerland and cut through the chalk at Dover about 6500 years ago were the populations separated. At this time prior to man draining the landscape in the last 1500 years there would have been masses of naturally wet habitat to maintain a thriving population of naturally regenerating BP. Poplar was still useful for timber right up until the last 150 years so despite the habitat loss, it was vegetatively kept going by man. It is only recently that the Italian subspecies and Populus balsamifera from America have been widely planted in preference to our native form as they grow straighter. Unfortunately, both hybridise with our native so as the reintroduction continues and landscape / wetland recovery gets going we may need to remove hybrid poplar to maintain genetic integrity. In essence given that populations have only been separated for a relatively short time I think the continental forms of P.n. ssp betulifolia will be pretty much the same.

Thankyou 🙂

Thank you! 😊