Olary Spur (Environmental Region 5.2)

This region consists of eight environmental associations. The Olary Spur is a low, easterly trending upland branching off the northerly trending Flinders Ranges. It comprises hogback ridges on metasediments and rounded granite hills, with shallow loamy soils supporting open shrubland of mulga, hopbush and turpentine bush, or a lower cover of saltbush and bluebush, locally with open mallee. Gentle footslopes and pediments commonly form extensive elongated intramontane plains with deeper duplex soils characteristically covered by saltbush and bluebush, commonly with scattered mulga or false sandalwood. There is a warm climate distinguishable by high evaporation and very low and unreliable rainfall throughout the year. Temperatures range generally from warm to hot in summer to cool to cold in winter. Evaporation is very high, particularly in summer, and exceeds the 90th percentile of monthly rainfall for every month of the year. Mean annual Class A pan evaporation ranges from about 2100 mm in the south of the region to about 2800 mm in the north. Mean annual rainfall ranges from 400 mm in the extreme south to less than 200 mm in the north. The views are commonly middleground panoramas with ridges and hills as local features as well as backdrops. Where ridges are closer together, foreground perspective views result. The rock of the ridges, exposed on the steeper slopes provides local detailed views. Background panoramas on the larger plains feature stream channels lined with red gums.