•Vegetation mounds, commonly found on sand plains, are large clumps or clusters of small trees and shrubs such as Acacia (tarfa) and Tamarix (tamarisk) with accumulations of sand at their bases, trapped by the vegetation. In this respect they are similar to very large, solitary coppice dunes, or to parabolic dunes. They differ, however, in size and distribution. Their size range overlaps slightly that of coppice dunes, but they may be as long as 80 m and as high as 20 m at Loot desert in Kerman province, Iran.
•It is likely that many vegetation mounds are relics of wetter environmental conditions, having started as coppice dunes formed around vegetation aligned along old water channels or around moisture-retaining basins. As the sand accumulated, the plants developed an ever more extended root system to reach water stored at the base of the mound. If the mounds build up beyond the ability of the plants to reach water, the vegetation will die.
•They are good sources of firewood, but because of the wildlife, particularly insects and snakes, they make poor places to camp. They offer almost the only areas for cover and concealment on sand plains, and they can also serve as observation posts.
•Shallow water can sometimes be found by digging beneath the sand in vegetation mounds, but it is likely to be saline. Also, there is a possibility of obtaining water from the old channels if mobile drilling equipment is available.
•The sand around Tamarix (tamarisk) mounds is frequently covered with fallen thorns, twigs, and branches that can produce annoying small puncture wounds in those sitting or lying on the surface. These thorns will easily puncture the soles of light desert boots with crepe soles, and they can cause leaks in tires.
In Lut desert in **Kerman province there is another type of them that is called Rebdou. These kind mounds, usually no more than about 1 to 5 m high, Another difference between Nebka and Rebdou is their appearance. Stone shape is more complex of wood. 'Rebdou' sometimes shows a few cones that have been together. The highest 'Rebdou' are seen in western Lut that their height sometimes reaches 12 m.