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Glasshouse experiments were used to determine the salinity tolerance of Atriplex nummularia (old man saltbush) either growing under free -draining or waterlogged conditions. Plants were grown over a 17 week period in either a sandy -clay or a sand and watered with saline solutions ranging from 0 -1000 mmol /L NaCl. All plants in free -draining pots survived the experimental period over the entire salinity range. Growth was slightly stimulated at the lower end of the range (100 -200 mmol /L) relative to that of the control where as growth was significantly reduced when salt concentrations exceeded 600 mmol /L. Growth at 1000 mmol /L was reduced to 54% of the control. Waterlogging significantly affected both growth and survival for all salinity levels other than the control. Growth was reduced to 50% at 100 mmol /L and to 22% from 400 mmol /L onwards. The lethal dose of salt that produced a 50% mortality (LD50) was 100 and 270 mmol /L for the waterlogged sandy -clay and sand respectively. Laboratory germination experiments showed that seed germination occurred under moderately saline conditions and that the level of salt tolerance increased significantly when the seeds were extracted from the bracts.