Wiktionary
n. (context mythology English) tree spirits, similar to dryads and hamadryads of Greek and Roman mythology. Like the hamadryads, they were bound to the tree they were born to for the life of the tree.
Wikipedia
Radande (Swedish plural radandar) are tree spirits in Swedish faerie mythology, similar to the dryads and hamadryads of Greek and Roman mythology. Like the hamadryads, they are bound to the tree they were born to for as long as it is alive. Also known as tree folk, it is said that they can take on a humanoid shape and venture a short way from their trees. In extreme cases they can even uproot the entire tree and use the roots as a shuffling locomotive. In their humanoid form they are often described as resembling their tree in clothing and facial features. Radandar are likely to grow at the centre of a fairy ring, to inhabit a lone tree on a hillside or the oldest tree in a grove, to grow beside a welling spring or to be one of two intertwined trees. They die if cut down but some believe that they linger on as spirits to haunt those who caused their demise. Trees have been believed to have magical properties or living spirits in nearly all cultures due to the ancient magic and mystery surrounding their life-span, strength and medicinal properties.