Communications in Soil Science and Plant Analysis, 41:1271–1281, 2010 Copyright © Taylor & Francis Group, LLC ISSN: 0010-3624 print / 1532-2416 online DOI: 10.1080/00103621003734281 Salt Separation Processes in the Saltcedar Tamarix ramosissima (Ledeb.) RUDY SOOKBIRSINGH, 1,2 KARINA CASTILLO, 1 THOMAS E. GILL, 2,3 AND RUSSELL R. CHIANELLI 1,2 1 Materials Research and Technology Institute University of Texas at El Paso, El Paso, Texas, USA 2 Environmental Science and Engineering Program University of Texas at El Paso, El Paso, Texas, USA 3 Department of Geological Sciences, University of Texas at El Paso, El Paso, Texas, USA Salt cedars (Tamarix) are invasive halophytic species and heavy water consumers. However, Tamarix possesses interesting characteristics accounting for its opportunistic and resilient abilities: analogous to a miniature photodesalinization machine, it thrives on saline soils toxic to most plants. Here we observe, document, and reveal the salt separation process of T. ramosissima. Specimens were cultivated under controlled arti- ficial conditions, then analyzed by microscopic and spectroscopic techniques. Tamarix ramosissima is shown to produce varied morphologies of salt crystal aggregates from vesiculated trichomes and possess the ability to separate anions and cations. Sodium chloride, potassium chloride (KCl), and potassium sodium sulfate [K 2.25 Na 1.75 (SO 4 ) 2 ] were major exuded salt crystal phases, with smaller quantities of other phases present. Compositions of crystals exuded by individual plants were consistent with compositions of the soils they grew on. Although T. ramosissima may be an invasive nuisance, it may possess other worthwhile attributes such as the potential to be a viable phytoremediator and environmental indicator. Keywords Halophytes, phytoremediation, salt cedar, Tamarix, vesiculated trichome Introduction Halophytic plants, classified as hydrohalophytes (salt tolerant) or xerohalophytes (aridity and salt tolerant), can sequester high concentrations of sodium and other salts in their aboveground tissue and secrete these concentrated salts through specialized salt glands called vesiculated trichomes. As a result of their unique ability to separate and exclude excess salts, the vesiculated trichomes or salt glands of xerohalophytic plants have been analogized to miniature desalinization machines. The genus Tamarix, known generically as salt cedars, comprises halophytic shrubs or small trees originally native to arid and semiarid regions of Eurasia and Africa. They have been introduced and/or invasively spread to many arid and semiarid parts of the earth. In western North America, T. ramosissima has spread aggressively along watercourses and Received 6 June 2008; accepted 11 August 2009. Address correspondence to Russell R. Chianelli, Materials Research and Technology, Institute University of Texas at El Paso, El Paso, TX 79968. E-mail: chianell@utep.edu 1271