A Psamment has no distinct soil horizons, and must consist entirely of material of loamy sand or coarser in texture.
They occur throughout the world, being especially abundant in the deserts of Africa and Australia and on the ancient landforms of eastern South America.
Areas dominated by Psamments also occur in other humid regions, notably in Florida and Nebraska (the Sand Hills).
The vegetation on Psamments varies enormously owing to the variety of climates, but in many cases is remarkably well-adapted to the climate, as with the Fynbos of the Cape region in South Africa—famous for its remarkable biodiversity and the equally species-rich Kwongan of southwestern Western Australia.
They are always much less productive than other soils in the same region even when fertilized, and require careful management because the sand is very easily eroded.