British Arboreal Research Department
The British Arboreal Research Department, or BARD for short, was a group created by the people of Great Britain on a future Earth who eventually relocated to a forested colony planet. It was used to create the artificial trees that could continually provide sustenance under the right conditions and be used as emergency stasis chambers, but these uses became forgotten and confused in legend over generations.
The department's logo was eventually adopted on the clothing of the people of the forest and was found on the forest bard's instrument, likely relating to the group's acronym. Although used as a musical instrument, this also controlled the trees' capturing abilities, as the Thirteenth Doctor discovered when Yasmin Khan and several other women were sacrificed as part of their Bridal Day. (COMIC: The Forest Bride)