A term for wild, off-the-wall theories. Named after a leading tinfoil-hat theory explaining the mysterious shaking, rustling trees on Lost during the first season of that program. The theory? The trees are having epileptic fits. Can be traced back to H.P. Lovecraft's story "The Colour out of Space".
Not only common, but expected for Mind Screw series. A major species of Tree is Everyone Is Jesus in Purgatory. An ongoing series which uses Chekhovs Guns to the point of becoming a Chekhov's Armoury encourages Trees because all newly introduced objects/people/skills/etc will be suspected of being a Chekhov's Gun. Horrible epileptic trees are known as Poison Oak Epileptic Trees.
See Stock Epileptic Trees for other common examples.
Epileptic Trees suggested by characters are a sign of Scully Syndrome. When an Epileptic Tree is rendered null and void by the official Canon, it's said to be Jossed. When an Epileptic Tree becomes Canon, you're allowed to say, "I Knew It!!" See also Inferred Survival, Urban Legend of Zelda and Schrodinger's Butterfly.