In the mid 1930's Leeper et. al. (1936) undertook a detailed soil and pasture study on a volcanic landscape consisting of young basalt flows around Mt Gellibrand in south-western Victoria, Australia. This study sought to provide “useful information concerning a group of soils about which little had yet been published”. This was undertaken just as soil science was becoming established in Australia and some of the first soil surveys were being conducted. It was a formative period when several new disciplines such as soil classification, field pedology and soil mapping were being developed. Some analytical techniques were relatively new and soil formation processes were just being proposed.

Leeper's study took place when no formal soil classification system existed anywhere in world. But this did not prevent the soil from being described; in fact it may have prompted Leeper to think further about soil classification. Indeed the soil descriptions probably provided a benchmark for future work. Leeper's ideas on soil classification provided a foundation for Northcote's (1979) Factual Key which was widely used for soil classification in Australia until recently. Some of the soil types described in Leeper's study were revisited and have been classified according to the current Australian Soil Classification (Isbell 1996). Leeper's description for some of these soils has been compared with the modern classification system. The benefits and drawbacks of each description are given.

Mt Gellibrand was an active volcano during the late Quaternary period. The estimated eruption age is 0.4 to 0.5 Ma (400 000 to 500 000 years ago) with flows of “stony rise” lobes, ridges and depressions. Consequently there exists considerable variation in the soils across this region. The topographic sequence of soil types – the ‘catena' – was a relatively new concept when this study was initiated. Milne (1935) introduced the term when classifying soils in East Africa. Subsequent studies in this region have built upon the catena pattern identified in this study. Soil genesis was explored through the study of features such as the gilgai The importance of erosion and the origin of minerals (namely the abundance of quartz), high Mg and low P was noted. Leeper acknowledged in this study that understanding was still developing in many areas and did not attempt to provide explanations for everything that was observed [the soil formation or the value of soil properties]. Since this study our understanding has improved in some areas, but there is no doubt that Leeper provided a solid platform of information on soils formed on basalt material in Australia.

Finally and perhaps one of the most useful contributions was the soil mapping component of Leeper's study. This study used aerial photography to assist in mapping the soil by identifying changes in vegetation and relief. This was only the second study to use this technique in Australia and is significant because it covers a relatively large area (4 850 ha) of a unique volcanic landscape. This mapping technique was strongly based upon the vegetation and/ or soil type relationship which was just developing at this time. The soil map was quite detailed and included nine different soil types. It is probably one of the first applications of remote sensing which as a field has since developed significantly.

Soil science in Australia has developed significantly in the last 70 years, and Leeper's early work made a significant contribution. Many of the properties characterised have proven useful in the development of understanding of soil genesis and the distribution of soils across a basaltic landscape. Whilst this study described the soils well, the need for soil classification was emphasised. Further the study provided a major advance in soil mapping by showing that aerial photography could be linked with topographic and vegetation features. Unfortunately, we have found that in some instances this study was possibly ignored by recent regional studies. However, we believe that there is still much to be learnt from this study both from its approach and content. It was conducted in a physically variable landscape and provided an excellent initial understanding of soils and landscapes in the Victorian volcanic plains region.

Isbell RF (1996) 'The Australian Soil Classification.' (CSIRO Publishing: Melbourne) Leeper GW, Nicholls A, Wadham SM (1936) Soil and pasture studies in the Mount Gellibrand area, Western District of Victoria. Proc. Roy. Soc. Victoria 49, 77-138. Milne G (1935) Some Suggested Units of Classification and Mapping, particularly for East African Soils. Soil Res. 4, 183. Northcote KH (1979) 'A Factual Key for the recognition of Australian Soils.' (Rellim Technical Publications)