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Abstract. Bladdder saltbush (Atriplex vesicaria) is used extensively as an indicator of land

condition in chenopod shrublands in South Australia. It is palatable, long lived, drought

tolerant and its occurrence is widespread over a wide range of soil types. In recent years the

SA Pastoral Lease Assessment Program has commonly found widespread mortality at rates in

excess of 90% for this species and while this is just one facet used to assess land condition, it

is important to understand if this is primarily due to management or climatic conditions. An

area in the Barrier Ranges Outwash IBRA subregion, consisting of five paddocks covering

161 km2 was monitored in 2011. This area had been voluntarily destocked by a land manager

since prior to the summer of 2001. Density transects in both the ungrazed and grazed areas

were examined and found to have mortality ranging from 98% to 99% in both stocked and

unstocked areas.

Adjusted rainfall data and models of ‘Growth’ developed by Australian Grassland and

Rangeland Assessment by Spatial Simulation (AussieGRASS)

(http://www.longpaddock.qld.gov.au/) are examined in data modelled back to 1890. The

number of consecutive years of low ‘growth’ from 2001 to 2009 is of the order of that in the

severe droughts of the 1960’s, 1930’s and 1890’s. This suggests that despite resilience of

bladder saltbush to drought, a threshold has been passed where most shrubs have not survived

and this has occurred even in the absence of grazing pressure.