Leuce (mythology)
In Greco-Roman mythology, Leuce or Leuka ("White" or specifically "White Poplar") was the most beautiful of the nymphs and a daughter of Oceanus. Pluto fell in love with her and abducted her to the underworld. She lived out the span of her life in his realm, and when she died, the god sought consolation by creating a suitable memorial of their love: in the Elysian Fields where the pious spend their afterlife, he brought a white tree into existence. It was this tree with which Herakles crowned himself to celebrate his return from the underworld.
Read more about Leuce (mythology): Mythology of The Poplar