Soil requirements of central Australian sandridge plants in relation to the duneswale soil catena

The soil requirements of seven central Australian sandridge plant species were examined by comparing the soils associated with individuals of each species in their typical sandridge habitats and in anomalous habitats such as dry watercourses, grader banks on road verges, disturbed ground near boreholes, and sand‐filled rock crevices. The species studied were Zygochloa paradoxa, Chamaesyce wheeleri, Calotis erinacea, Helichrysum ambiguum, Dampiera cinerea, Triodia basedowii and Monachather paradoxa. The first two of these are characteristic of open dunecrests, the next three of crests and upper dune slopes, and the last two of lower slopes and swales. The first five species grow in a range of anomalous habitats with nutrient status comparable to swales and lowerslopes, but only if the soils are loosened or have enhanced moisture status. The deep wellsorted sands of dry watercourses form the only anomalous habitat for Zygochloa paradoxa and Chamaesyce wheeleri. Calotis erinacea, Helichrysum ambiguum and Dampiera cinerea also grow on poorly sorted graderbank and borehole soils in the swales, but not on unmodified swale soils. The only anomalous habitats in which the last two have been found are very similar to their typical sandridge habitats and so reveal little of soil requirements.