Atriplex are C-plants, with a characteristic leaf anatomy (kranz anatomy). The genus "Atriplex" is distributed nearly worldwide from subtropical to temperate and to subarctic regions. Most species-rich are Australia, North America, South America and Eurasia. Many species are halophytes and are adapted to dry environments with salty soils. The genus evolved in Middle Miocene, the C-photosynthesis pathway developed about 14.1-10.9 million years ago, when the climate became increasingly dry. The genus diversified rapidly and spread over the continents. The C"Atriplex" colonized North America probably from Eurasia during the Middle/Late Miocene, about 9.8-8.8 million years ago, and later spread to South America.
Hydric soil adopting this definition in 1985, Congress attempted to capture the duration of waterlogged condition of a hydric soil by adding that a hydric soil is waterlogged long enough to support not only the growth of plants adapted to life in anaerobic conditions but also the regeneration of such plants. Another common definition of a hydric soils is provided by the National Technical Committee of Hydric Soils (NTCHS) as "a soil that formed under conditions of saturation, flooding, or ponding long enough during the growing season to develop anaerobic conditions in the upper part." The NTCHS hydric soil definition is used