Some of the biggest obstacles in soil sampling are convenience and cost for landowners. Soil sampling provides a tremendous amount of information to a land manager about the biological, chemical, and physical make-up of soil. However, it requires someone to go out into the field with a soil probe, collect and process the samples, and then ship them to a lab for analysis. On a large property, the amount of sampling required can be daunting–dozens or even hundreds of samples per year. Over time and many samples collected, the cost of simply shipping the soil alone can be prohibitive enough for many landowners to forego the sampling altogether. But what if they could sample right in the field taking as many samples as they want and get real time feedback?

Recently, scientists from the Yale School of Forestry and Environmental Studies UCross Plains High

Stewardship Initiative stopped by TomKat Ranch to share an affordable (less than $500) pocket-sized spectrometer that shows great promise in reducing the need for conventional soil sampling. It’s not meant to entirely replace traditional methods, but to reduce cost and provide feedback more frequently, at a finer resolution, and over broader areas to inform management decisions.

Using the reflectance of soils in the visible and infrared spectra, the pocket-sized device measures soil carbon through color. For example, a soil with higher carbon will be darker, giving it a different spectral signature than a soil with lower carbon content. Using this device, land managers can quickly and cost-effectively create a custom map of their fields that shows the carbon stocks. Over time, this information will help illuminate the effects of management decisions and help them zero in on what’s helping them put carbon productively in their soil and what’s not.

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Dan Kane, inventor of the pocket soil carbon spectrometer, surveys the land.


Field tests have been very promising and the platform is built on an open-source hardware/software platform that integrates with an Android phone to automatically provide sample coordinates. By reducing the time and cost required to sample, this device can give land managers the ability to conduct many more tests than with typical sampling procedures, providing a valuable, rapid feedback loop to inform which land management decisions and practices are effective across a large area.

The TomKat Ranch Summer Interns were lucky enough to get a chance to go out in the field and test the new pocket spectrometer to help provide calibration data for our region. We want to thank our friends from Yale for providing a valuable experience for the interns, and we look forward to learning more about how we can employ tools like this at TomKat Ranch in the future.