Mocking Trees were a specific kind of tree. The Duros couple Etro and Droza Edthatt, who had just been newlywed, were once taken against their will by Humans from what they thought was the planet "Urthha." On that planet, the Edthatts perceived their captors' speech as a "high-pitched gibberish," which evoked the image of Mocking Trees for them. This comparison appeared later in an article about the couple's abduction in the August 8, 6094 edition of the The Galactic Gossip periodical.
The book Monsters and Aliens from George Lucas, published in 1993, mentioned Mocking Trees. This book blends creature designs and images from different projects by George Lucas, the creator of the Star Wars saga, with original writing by Bob Carrau. Leland Chee, an employee of Lucasfilm who is in charge of the Holocron continuity database, has stated that the details in Monsters and Aliens from George Lucas are considered non-canonical within the Star Wars Legends continuity.