Home to a spiritual society, Madrona basks in rich beauty and agriculture as the planet is ideally supported by a mysterious device left behind by a long-dead society: the Touchstone, permitting any variety of desirable weather conditions.
Without the Touchstone, Madrona reverts to an apocalyptic, ice-age climate, where snow and lightning abound. The water sources freeze and gale-force winds destroy the settlements. With the Touchstone reinstated, the planet instantaneously reverts to an ideal state.
Earth's designation for Madrona is PX7-941.
Touchstone - A rogue N.I.D. group snatches the Touchstone and destroys the climate conditions of Madrona until SG-1 returns the device to its proper owners.
Fallout - Teal'c refers to Madrona (as "Madronas") as a possible place to relocate the Langarans.