The planet Dryad was home to a race of humanoids dubbed Dryads.
They were sentient, silicon, rock life forms that had lain in a dormant state while observing the newcomers before determining that they had no hostile intentions. One of the race Strata was kidknapped by the Dominators. She freed herself along with other prisoners and formed a galatic police force called the L.E.G.I.O.N.. During her service she met another of her race Grav. The pair married and had a child called Rocky
Dryad was destroyed in the latter days of the 30th Century because of instability in its radioactive core. Human colonists had settled the planet an dubbed this the Korlon colony. For many years, the Korlon colonists believed the world to be uninhabited until its native population revealed itself.
The human and native neighbors existed in harmony until the discovery of Dryad's imminent destruction. The United Planets and the Legion of Super-Heroes evacuated as many inhabitants of the planet as was possible, relocating the humans on allied United Planets worlds. The natives elected to go into their dormant state and to be sent into space; they would revive when they encountered worlds capable of supporting their particular form of life.
One of the few native Dryads not to follow his people was Blok of the Legion of Super-Heroes. Blok was still a young form of his species; as they age, Dryadans enter a period known as the "gendering," when they shed their outer skin and discover which sex they are. As they get older after the gendering, Dryads grow larger and slow down, eventuality spending much of their time in dormancy.