Nearctic Desolate Desert - Code: Ne2D

Nearctic Desolate Desert is a broad assemblage of landforms scattered throughout the desert habitats of North America. These areas are united by a lack of permanent vegetation and a corresponding dearth of wildlife. Nearctic Desolate Desert includes areas of bare plateau, stabilized dune systems, ergs (moving sand dunes that support little vegetation), desert pavements or regs, and clay or salt pans. Nearctic Desolate deserts occur in a wide variety of arid environments and temperatures here can range from 125°F (52°C) in the Mojave and lower Sonoran deserts to 5°F(-15°C) in northern Nevada.
This habitat typically has woody shrub cover on less than 2% of the surface. The few tiny shrubs found here are usually creosote (Larrea tridentata) or saltbush (Atriplex spp.). Desert pavements, pans and scree slopes will occasionally experience large blooms of herbaceous plants following rare rain events. Common plants in these blooms include Devil’s Spineflower (Chorizanthe rigida), Desert Trumpet (Eriogonum inflatum), and Desert Sunflower (Geraea canescens). Ergs, dune fields and sand flats can develop sparse vegetation if properly protected from wind and stabilized. Most of the plants here are stoloniferous grasses (especially Swallenia spp.) that grow clonally from runners under the sand before sprouting. Other herbaceous plants found on dunes include Desert Sand Verbena (Abronia villosa), Basket evening primrose (Oenothera deltoides), and croton (Croton spp.). An odd fuzzy tuber dotted in purple flowers called Sandfood (Pholisma sonorae) can be found in the dunes as well. Sandfood is a parasite that takes nutrients (but not water) from various sparse desert shrubs. The plant was an important food source for indigenous people during difficult desert crossings.
Vegetation does not usually grow in these environments for several reasons. A few of them are too dry, with extremely low rainfall and extremely high temperatures. This is especially true in parts of the Mojave and Vizcaíno where annual rainfall is often less than 4 in (100mm). Many of the low valley pans are too saline or too alkaline for plant growth. In Ergs and dune fields settings, the substrate is too unstable and constantly shifting for plants to becomes established. 
The most common form of Nearctic Desolate Desert is reg or desert pavement. Reg is formed when fine soils erode between small pebbles. Over time, wind and occasionally water will winnow down these small rocks and create pavements of interlocking stones. As regs age further they develop a desert varnish a shiny thin patina of clays, iron, and manganese baked onto the surface.