From Hell It Came

Silly horror film set on a faraway south-sea island. Native prince Palmer is sentenced to death by witch doctor Swan for fraternizing with white scientists Andrews and Carver, who are investigating the radiation residue left over from an atomic bomb blast. Swan stabs Palmer in the chest and buries him upright in a coffin, but not before the prince vows vengeance. Soon after, he keeps his promise by coming back to life as a walking tree stump (with a stern look on his face) that grows out of the grave. The tree monster then lumbers around getting his revenge on those who murdered him until he eventually wanders into some quicksand and disappears. Really goofy.