In general, drought-tolerant plants with fiberous roots (not tap roots) like succulents and low grasses are best; sod is too water-intensive, and moss is a fire hazard.

The key in plant selection is to select plants for the environment you are creating – not the environment you are building in.

Oh, and don’t use plants, like certain prairie grasses, that burn every few years as part of their natural ecology. this is generally a bad idea.