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In Part 2 of our soil texture series, we get practical.

Leonie walks through how to measure soil texture in the paddock using the classic hand-texturing and ribbon test and explains how particle size analysis works in the lab, including the clever physics of Stokes’ Law that lets scientists separate clay from silt.

You’ll also learn how to read the texture triangle, and why the same soil can be given different names depending on which country the research comes from. This international difference in particle-size boundaries is one of the most useful (and most overlooked) things to understand when reading global soil science.

We finish by looking at how texture changes down the profile (uniform, gradational and duplex soils) and the practical decisions texture drives on farm: water storage, nutrient holding, salinity risk and carbon.

A clear, practical episode for anyone who wants to move from knowing the words “sand, silt and clay” to actually using them with confidence.

Reference List

Barton, L. (n.d.). ENVT2236 Soil Science laboratory manual [Unpublished course material]. School of Agriculture and Environment, The University of Western Australia.

Brown, K., & Wherrett, A. (n.d.). Measuring soil texture in the lab [Fact sheet]. Soil Quality. https://www.soilquality.org.au/factsheets/soil-texture-measuring-in-the-lab

Department of Primary Industries and Regional Development. (2024). Estimating soil texture by hand [Fact sheet]. Department of Primary Industries and Regional Development, Western Australia. https://library.dpird.wa.gov.au/nrm_factsheets/1

Galloway, P., van Gool, D., Stuart-Street, A., Griffin, E., Pathan, S., & Schoknecht, N. (2024). Western Australian soil groups: A diagnostic key to identify soils in Western Australia (5th ed., Resource Management Technical Report 427). Department of Primary Industries and Regional Development, Western Australian Government.

Minasny, B., & McBratney, A. B. (2001). The Australian soil texture boomerang: A comparison of the Australian and USDA/FAO soil particle-size classification systems. Australian Journal of Soil Research, 39(6), 1443–1451. https://doi.org/10.1071/SR00065

National Committee on Soil and Terrain. (2024). Australian soil and land survey field handbook (4th ed.). CSIRO Publishing.

Pluske, W., Boggs, G., & Leopold, M. (2018). Soil quality: 2. Integrated soil management. SoilsWest. https://soilqualityknowledgebase.org.au/soil-texture/

Pluske, W., Murphy, D., & Sheppard, J. (2018). Integrated soil management (Soil Quality ebook series, Book 2). SoilsWest, The University of Western Australia.

Soil Quality. (n.d.). Measuring soil texture in the field [Fact sheet]. https://www.soilquality.org.au/factsheets/soil-texture

Stuart-Street, A., Short, N., Galloway, P., & Schoknecht, N. (2025). A simple guide for describing soils (2nd ed.). Department of Primary Industries and Regional Development, Western Australian Government.

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Website: www.agriculturefromthegroundup.com.au

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This episode explains what soil texture really is. Leonie breaks down the three mineral particles that make up texture — sand, silt and clay — and shows that the difference between them is simply particle size.

Key points covered:

• Texture is an inherent soil property that does not change in a human lifetime
• Exact size ranges used in Australia for sand, silt and clay
• Why gravel and stones are excluded from texture
• Why clay has such high surface area and nutrient-holding ability
• How texture groups (sands, loams, clays) and texture grades are named

The episode ends by previewing Part 2, which will cover how to measure texture by hand and in the lab, and an important international difference in particle-size definitions.

New episodes every Wednesday!

Reference List

Brailsford, F., Scanlan, C., Weaver, D., Holmes, K., & Leopold, M. (2023). Gravel soil (Soil Quality ebook series, Book 9). SoilsWest, Murdoch University.

Farm Weekly. (2020, July 14). New guide to understand soil profiles. https://www.farmweekly.com.au/story/6832206/new-guide-to-understand-soil-profiles/

National Committee on Soil and Terrain. (2024). Australian soil and land survey field handbook (4th ed.). CSIRO Publishing.

Pluske, W., Boggs, G., & Leopold, M. (2018). Soil quality: 2. Integrated soil management. SoilsWest. https://soilqualityknowledgebase.org.au/soil-texture/

Pluske, W., Murphy, D., & Sheppard, J. (2018). Integrated soil management (Soil Quality ebook series, Book 2). SoilsWest, The University of Western Australia.

Stuart-Street, A., Short, N., Galloway, P., & Schoknecht, N. (2025). A simple guide for describing soils (2nd ed.). Department of Primary Industries and Regional Development, Western Australian Government.

Connect with Leonie
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Website: www.agriculturefromthegroundup.com.au

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In this episode of Agriculture From The Ground Up, Leonie sits down with Tim Overheu (Principal Research Scientist, past National President of Soil Science Australia, and one of Western Australia’s most experienced soil scientists).

With more than 30 years of hands-on experience across WA’s unique landscapes, Tim shares practical insights into:

• How parent material shapes the soils we farm today
• Why Western Australian soils are both ancient and surprisingly young
• What soil horizons (those “Lego blocks” in the profile) are really telling us
• The role of bleached horizons, and duplex soils
• Why WA farmers have become masters at working with difficult sandy landscapes

Tim also explains the influence of wind-blown sands, dolerite dykes, and the living, changing nature of our soil profiles and why understanding what’s happening just below the surface can make a real difference on farm.

Whether you’re a grower, agronomist, or simply curious about the ground beneath your feet, this conversation will help you see your paddocks in a whole new way.

Connect with Leonie
Instagram: @agfromthegroundup
Website: www.agriculturefromthegroundup.com.au

Connect with Leonie
Instagram: @agfromthegroundup
Website: www.agriculturefromthegroundup.com.au

Send us Fan Mail

In this episode of Agriculture From The Ground Up, we connect the dots between parent material and the soil profiles you dig into every season.

Leonie walks through the CLORPT framework (Climate, Living organisms, Relief, Parent material, Time + humans), explains the important difference between layers and true soil horizons, and unpacks the four soil-forming processes that create the profiles we see in the paddock.

You’ll also learn how to read the master horizons (O, A, E, B, C and R) and how the Australian Soil Classification helps us name and understand common WA soils such as Tenosols, Chromosols, Sodosols and Kandosols.

This is practical knowledge you can use the next time you dig a hole, because every horizon tells a story, and understanding that story helps you make better decisions on farm.

Reference List

Birkeland, P. W. (1999). Soils and geomorphology (3rd ed.). Oxford University Press.

Carson, J. (n.d.). Soil biological fertility. soilquality.org.au. https://www.soilquality.org.au/factsheets/soil-biological-fertility

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., & National Committee on Soil and Terrain. (2016). The Australian soil classification (2nd ed.). CSIRO Publishing.

Jenny, H. (1941). Factors of soil formation: A system of quantitative pedology. McGraw-Hill.

Leopold, M. (2020). ENVT4401 Advanced Land Use Management [Lecture notes]. University of Western Australia.

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.

Orr, T. J., & Roberts, E. M. (2024). A review and field guide for the standardized description and sampling of paleosols. Earth-Science Reviews.

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.

Connect with Leonie
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Website: www.agriculturefromthegroundup.com.au

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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

Send us Fan Mail

Welcome to the very first episode of Agriculture From The Ground Up: a practical video podcast series dedicated to bridging cutting-edge soil science with real on-farm application in Western Australia and beyond.

Hosted by Leonie Smith; an aspiring soil scientist, agricultural educator, former farm manager, and mum of four. This introductory episode explains why this podcast exists and what you can expect. With over 10 years of hands-on experience managing soils on south coast of WA and SA properties, roles at BHP Billiton Ravensthorpe Nickel Mine, Southern Dirt drought resilience trials, TAFE and university delivery at SRTAFE, UWA and Murdoch, two agriculture masters and current research on deep spading and clay incorporation, Leonie is passionate about making complex agriculture topics accessible and actionable.

In this episode, discover:

• The "why" behind the podcast: closing the gap between research and practical farming decisions on sandy and duplex soils.
• How we'll cover the fundamentals: starting with soil parameters, moving to roots and the rhizosphere, then plants and systems.
• What to expect in future episodes: ~20-minute video episodes featuring expert guests (DPIRD, GRDC, university researchers, and more), on-farm updates with agronomist Alec Smith, visuals, demos, and short clips for quick insights.
• Focus areas including soil constraints (acidity, compaction, water repellence, etc.), amelioration techniques like rotary spading, soil organic carbon, drought resilience, and regenerative practices, then moving to plants and livestock.

Whether you're a farmer looking for better yields and soil health, an agronomist, student, or anyone interested in agriculture, this series is for you.

Subscribe now on your favourite podcast platform, watch the full video episode, and join the conversation! Drop a comment or message with your biggest soil challenge — we’d love to feature listener questions in future episodes.

New episodes drop regularly. Let's build healthier soils and more resilient farms from the ground up.

#SoilScience #WesternAustraliaAgriculture #SoilAmelioration #RegenerativeAg #DeepSpading #FarmersPodcast

Connect with Leonie
Instagram: @agfromthegroundup
Website: www.agriculturefromthegroundup.com.au

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In this foundational episode, Leonie explores the very beginning of soil: parent material. Discover why two farms just 10 kilometres apart can perform so differently, even when they get the same rainfall and use the same varieties.

You’ll learn:

• What parent material really is (and the difference between residual and transported material)
• The three main rock types (igneous, sedimentary, metamorphic) and the very different soils they produce
• Why WA soils are naturally sandy, acidic and low in nutrients
• What ironstone gravel, coffee rock, lateritic duricrust and rocky outcrops actually are — and why they matter on your farm
• How understanding what’s under your paddocks can help you make smarter management decisions

Whether you’re dealing with deep sands, duplex soils, ironstone gravel or coffee rock hardpans, this episode will help you start “reading” your farm’s geological recipe and farm it more effectively.

All visuals form the video podcast are available on our website at www.agriculturefromthegroundup.com.au

References

Birkeland, P. W. (1999). Soils and geomorphology (3rd ed.). Oxford University Press.

Brailsford, F., Scanlan, C., Weaver, D., Holmes, K., & Leopold, M. (2023). Soil quality: 9 Gravel soil. SoilsWest / Murdoch University / GRDC. https://library.dpird.wa.gov.au/sq_ebooks/9/

Eash, N. S., Sauer, T. J., O'Dell, D., Odoi, E., & Bratz, M. C. (2015). Soil science simplified (6th ed.). Wiley.

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/

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

Connect with Leonie
Instagram: @agfromthegroundup
Website: www.agriculturefromthegroundup.com.au