on coarse gravelly calcareous silts of alluvial bluff above Rio Grande River with Schaefferia cuneifolia, Heliotropium confertifolium, Karwinskia humboldtiana, Leucophyllum frutescens,Aloysia macrostachya, Vachellia rigidula, Forestieria angustifolia, Ephedra antisyphilitica, Jatropha dioica, Sida tragiaefolia, Lippia graveolens, Guaiacum angustifolium, Calliandra conferta, Krameria ramosissima.
