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Maireana sedifolia (bluebush) is a common chenopod bush growing throughout arid and semiarid regions of Australia. At the base of this plant there is usually a mound where smaller, annual species grow preferentially. A survey was conducted to examine the size of the mounds and the vegetation growing on them under different grazing regimes. This survey was conducted at Koonamore Station, South Australia. Comparisons were made between inside a vegetation reserve which has excluded sheep since 1925, and outside the reserve in lightly and heavily grazed areas. Mound heights were measured for bushes in each of the grazing regimes and a survey conducted on plant abundance and lichen cover beneath bushes and in open areas. Mounds were significantly higher in the heavily grazed area. There were more plants growing under the bushes compared with the open areas in all paddocks, and there were more plants inside the reserve for both positions. Lichen cover below the bushes remained the same in all paddocks but the heavily grazed site had significantly lower lichen cover values in the open areas. Results indicate that grazing pressure affects the mound height, the vegetation present and the lichen cover. It is hypothesised that the mounds are developed by the degradation of areas around the bushes rather than just through the accumulation of materials, as previously thought. The importance of such 'safe sites' for annual species is therefore likely to be greater in areas of heavier grazing.