None of them are designed for the kind of impact that occurs when you insert an electrode into a core of soil. However, for pH they work fairly well. For nitrate, potassium and some other...

Although the pH sensor doesn’t necessarily tell you the lime requirements, it does identify field areas needing lime. We use it to show the highs and lows on a map. Then we take manual soil...

You do this in mid-growth, when the plant just starts showing signs of nutrient stress that the human eye is not yet able to detect.

So far, using autonomous robots to make soil measurements is somewhat futuristic. In general, robotics for scouting still has many limitations, including providing them with enough power to operate efficiently for long periods. However, hypothetically,...