ECOLOGY OF CALLITRIS-GLAUCOPHYLLA (CUPRESSACEAE) ON THE MACDONNELL RANGES, CENTRAL AUSTRALIA

A geographic survey of 17 stands of Callitris glaucophylla on the MacDonnell Ranges, in central Australia, revealed that the pine occurs on sites ranging from flat, sandy creek beds to rocky, north or south facing slopes, with the majority of the sampled stands occurring on steep (35-degrees) south-facing slopes. A quadrat based (n=100) floristic survey on an outlying ridge from the MacDonnell Ranges also showed that C. glaucophylla has a wide ecological niche, although the species had a significantly negative association with sites that lacked boulders (> 0.5 m diameter) and significantly positively associated with south-facing slopes. The widespread occurrence of dead C. glaucophylla stems and the lack of associated regeneration indicate that species distribution is currently contracting. We suggest that the fragmentary distribution of the species is strongly controlled by wildfire.