Episode 3: Where in the World Did Your Soil Come From? A Global Tour of Soil Formation

Why do Scottish farms look so green and productive while many WA Wheatbelt soils are sandy and naturally low in nutrients? The answer isn’t farming skill or climate alone; it’s geology and the age of the parent material. In this episode, Leonie takes you on a global tour of soil formation: from glaciers grinding fresh rock in Scotland and loess-blown fertility in the American Midwest, to volcanic soils in East Africa and the deeply weathered ancient landscapes of Western Australia and parts of Africa. You’ll discover why most of the world’s great farming regions sit on “young” soils, while WA’s soils tell one of the oldest stories on Earth. Back on home soil, we zoom in on the Yilgarn Craton, laterites, coffee rock, and what this ancient geological inheritance really means for practical farm management in WA. Plus, key takeaways on why we can’t always copy practices from overseas or the eastern states — and how understanding our soils’ unique story helps us farm them better. Whether you’re a farmer, student, or soil enthusiast, this episode delivers plenty of “aha!” moments and a deeper appreciation for the living skin beneath our feet. Key Topics: • Young vs ancient parent material and why it matters • Glacial till, loess, volcanic ash, and laterites around the world • WA’s unique geological story (Yilgarn Craton, deep weathering) • Practical takeaways for Wheatbelt farming References Birkeland, P. W. (1999). Soils and geomorphology (3rd ed.). Oxford University Press. Hoyle, F. C., & Murphy, D. V. (Eds.). (2017). Soil quality: 1. Constraints to plant production. SoilsWest / Department of Primary Industries and Regional Development. https://library.dpird.wa.gov.au/sq\_ebooks/1/ Isbell, R. F. (1996). The Australian soil classification system. Australian Soil and Land Survey Handbook Series. CSIRO Publishing. Jenny, H. (1941). Factors of soil formation: A system of quantitative pedology. McGraw-Hill. Leopold, M. (2020). Advanced land use management \[Lecture notes]. University of Western Australia. McArthur, W. M. (1991). Reference soils of south-western Australia. Australian Society of Soil Science Inc. (WA Branch). McKenzie, N., Jacquier, D., Isbell, R., & Brown, K. (2004). Australian soils and landscapes: An illustrated compendium. CSIRO Publishing. Moore, G. (Ed.). (2001). Soil guide: A handbook for understanding and managing agricultural soils (Bulletin 4343). Department of Agriculture, Western Australia. Weil, R. R., & Brady, N. C. (2016). The nature and properties of soils (15th ed.). Pearson. White, R. E. (2006). Principles and practice of soil science: The soil as a natural resource (4th ed.). Blackwell Publishing. Wilde, S. A., Valley, J. W., Peck, W. H., & Graham, C. M. (2001). Evidence from detrital zircons for the existence of continental crust and oceans on the Earth 4.4 Gyr ago. Nature, 409(6817), 175–178. https://doi.org/10.1038/35051550 **Connect with Leonie** Instagram: @agfromthegroundup Website: www.agriculturefromthegroundup.com.au **Connect with Leonie** Instagram: @agfromthegroundup Website: www.agriculturefromthegroundup.com.au