A collumn of rock is best made using a symettrical lattice. Using greyscale to height-mapping in the terrain editor to create the shape. As for making a texture like the one on Ang25's hoodoo you can look at a few of the preset textures from planes&terrains and rocks&stones in the texture library. I can't give you any screenshot's rightnow, because I'm not on my bryce-station. I hope this answers your question (or at least part of it).

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