Winterfat (Ceratoides lanata) is a long-lived shrub with excellent drought tolerance and good to moderate tolerance for herbivory. It often occurs as near monocultures in deep finetextured soils of alluvial fans and valley bottoms. Winterfat communities are second only to those of shadscale (Atriplex confertifolia) in dominance of the 16 million ha of salt-desert shrublands found in Western North America. In spite of improved grazing practices, winterfat is declining in many areas of the Great Basin. The Eurasian summer annual, halogeton (Halogeton glomeratus), is well adapted to the soils and climate associated with winterfat communities and is invasive, replacing winterfat on degraded sites. Recolonization of halogeton stands by winterfat is rare. Subsequently, distinct winterfat- and halogeton-dominated communities often occur side by side. At the Desert Experimental Range (Utah), episodic winterfat mortality at the ecotone has been observed particularly after flood events and periods of higher than average precipitation. The upward translocation and accumulation of cations, particularly sodium, in the soil by halogeton may account, at least in part, for the lack of winterfat establishment in halogeton stands. Other evidence suggests that a possible halogeton- induced change in soil microbiota may also be unfavorable for winterfat. The development of viable management options to restore winterfat communities will require a greater understanding of plant-soil interactions for these species.