This magnificent tree stands above the upper reservoir on the south side of the Beck.
Native Black Poplar is a rare tree in the UK. There are probably fewer than 7000 individuals and only about 600 of these are female.
Yorkshire is at the northern edge of its range: there appear to be only a handful in the county.
The situation is clouded by the existence of hybrids (which are much commoner). However, these generally lack the downswept branch form and have rounder leaves. We will have to wait until spring to sort out whether this individual is male or female.