Black poplar is Great Britain’s rarest native hardwood and there is considerable interest in conserving the genetic diversity present in the remaining population. However, multiplication by vegetative propagation has led to issues in identifying and selecting genetically diverse native planting material. The ability to use DNA markers to identify poplars at the level of the individual enables conservation efforts to be directed to deploy and maintain the current genetic diversity. This Research Note summarises the results from the DNA fingerprinting of 811 non-hybrid black poplars which identified a total of 87 clones. The results split the British black poplar clones into two groups, a small group which contains individuals with a large number of rare alleles (rare alleles are DNA variants occurring at a low frequency in a population) and a larger group containing less diversity and the more common alleles. In terms of their geographical distribution, some clones had a restricted distribution whereas others were widespread. The results highlight that the British native black poplar population has clearly been influenced by human intervention and, due to a number of historical factors it rarely acts as a naturally sexually regenerating species. Black poplar needs to regenerate sexually if it is to respond to environmental changes and management should aim to provide the conditions required for seed germination. DNA-based clonal identification can be utilised to ensure the current genetic diversity in the British population is protected into the future.