Delta Gamma IV was a class M planet, the fourth planet of the Delta Gamma star system, located in the Beta Quadrant between the Federation and the Klingon Empire. The planet was native to a species of plant which were nicknamed "Oz poppies" and a species of telepathic rodents.
Prior to 2269, Delta Gamma IV had been visited only briefly by one scouting expedition, in the winter, in the southern hemisphere. That year, the Federation starship USS Enterprise was sent there to determine its suitability as a Federation colony under the terms of the Organian Peace Treaty. A landing party consisting of James T. Kirk, Spock, M'Benga, Jeffrey Carter, Bobby Robinson, Grace Temple, Jamison, Matthews, and Miriam Raymond was beamed down to the planet's northern hemisphere in summer, where they became infected with the poppies' psionic-boosting spores, the latter three dying of the infection. (TOS novel: Death's Angel)