Between the original books and more recent sequels, just about every substance has been made into a character or group of characters in Oz. Mushrooms are no exception, appearing in two of Eric Shanower‘s stories. Both of these appeared in Oz-Story Magazine, the first written and second published being Trot of Oz, which Eric co-wrote with Glenn Ingersoll. They started writing this in 1982, after mushroom people had already appeared in some other works. This was before Mario and Luigi would encounter the residents of the Mushroom Kingdom in the original Super Mario Bros., and I believe around the same time that myconids were first introduced in Dungeons & Dragons. They’re apparently pretty common in Japanese media, including a 1963 film called Matango, which was translated into English as Attack of the Mushroom People. I also remember trying to read one of Eleanor Cameron’s Mushroom Planet books, although I don’t think I ever finished it. Written in the 1950s, these tales concerned people with mushroom features who lived on a planetoid orbiting the Earth, some of whom had also come to make their homes on Earth. I can’t say I’m familiar with most of these, aside from the Mario games. Fungoid people are probably just an idea without any one source, as are people with animal and plant features.
The mushroom civilization in Trot is located beneath Lake Quad, near the Emerald City. Their dwelling place is in Shroom City, formerly a place made up giant mushrooms, but in shambles when Trot and Cap’n Bill visited there. These people, the Shrooms, have no necks, shoulders, or bones; and antennae grow out of their foreheads.
The Stels are similar, but are thinner, have bulbous eyes, and are unable to speak. They perform physical labor, while the Shrooms are divided into scientists, artists, and priests. The latter keep the Multiplying Overcoat, which is made up of the souls of dead Shrooms.
The Overcoat can produce duplicates of an individual, but only if that person has five fingers; Shrooms can have anywhere between two and six. A Shroom scientist named Rottug caused trouble when he stole the Overcoat and used it to his own devious ends, setting up an ally to serve as a figurehead despot.
After an adventure, a Shroom named Shruvm absorbed the power of the Overcoat and became the new leader, founding a new city for his people.
The other mushroom story, “Dorothy and the Mushroom Queen,” first appeared in Volume 2 of Oz-Story under the pseudonym Janet Deschman, and was later included in The Salt Sorcerer of Oz and Other Stories under Eric’s own name. Here, the Glass Cat discovers a group of mushroom people dancing in the moonlight in a Munchkin forest, and later returns with Dorothy and Flicker to explore their homeland. The underground land of Ma-dul-ma-dun turns out to be ruled by Queen Piopelp, who is obsessed with beauty.
Her subjects spend their time carving out the history of the nation in the cavern walls, and creating art in the caves. Their population is dying out, as they need to bathe in moonlight to remain alive, and the Queen only allows her favorites outside with her. The people drown anyone who doesn’t meet their standards of beauty in a whirlpool, and those who die release spores to produce new people. Exposure to sunlight is deadly for these mushroom people.