The Mushroom Forest is an area in the Diablo Desert that has a large amount of vegetation, primarily giant mushroom trees.
It is an area visited in Dragon Ball: Dragon Daihikyou. In Dragon Ball: Origins, it is a stage where Goku must look for Monster Carrot's Hideout and then defeat a T-Rex. It is also where he found the "Curvy Lady" he brought to Master Roshi. In the bonus level 5-6 in this video game, Nam was seeking food for his village after the 21st World Martial Arts Tournament when he ate a mushroom from this forest that made him unbearable; Goku must defeat Nam to reason him after he found him in Monster Carrot's Hideout.