Can We Unlock the Secrets Beneath our feet with the Next Era of Soil Health Testing?

Agriculture in New Zealand is fundamentally rooted in the soil beneath our feet, with soil health being critical to the success of farmers and the broader agricultural sector. Soil is the most valuable asset of a farming operation however; soil health remains difficult to assess and measure.    

Current soil tests focus on the physical and chemical characteristics of soil, such as pH and nutrient levels. However, these traditional tests provide little insight into the biological aspects of soil health, such as microbial activity and earthworm populations, which are crucial for soil fertility and longer-term sustainability.  

Technical innovations in molecular DNA testing are revolutionising how soil health is understood and managed, providing insights that were previously unavailable through traditional methods. Molecular testing can identify bacteria, fungi, archaea, protozoa and microscopic invertebrates, many of which play a critical role in nutrient cycling, plant health and carbon storage. 

Some potential applications where molecular DNA testing can help measure and understand indicators of soil health include: 

• Ability to monitor and understand the diversity and abundance of microbial communities 

• Detect and track beneficial organisms 

• Early detection of soilborne diseases and detection of invasive biosecurity threats 

• Aid improved soil fertility management 

• Measure impact of land use practices 

• Support regenerative and organic farming 

The abundance of earthworms in soil is another measure that often serves as a biological indicator of soil health. Traditionally, assessing earthworm populations requires visual field assessments, which are labour-intensive and require specialist knowledge. Our eDNA test does not replace a visual field assessment. It provides an alternative testing method that represents the entire paddock by using a soil transect, rather than the worm population from a single location. Used in tandem, our eDNA test with visual field assessments provide a convenient way to monitor soil health.  

The ability to more easily estimate earthworm populations in soil allows farmers to make informed decisions about soil management and provides off-farm entities an independent view of farm management practices. It provides farmers with a quick way to measure a key indicator of soil health, enabling more informed and efficient management decisions to improve fertility and sustainability.  

Exciting advances in molecular DNA testing are opening more opportunities to reveal new insights into the complex world of the soil beneath our feet. Hill Labs is looking forward to expanding our services to support the next generation of soil health analysis.