Soils are anything but monolithic; chemistry, soil type, management history, and, ultimately, yield potential vary acre by acre and inch by inch. Farmers must balance the precision of intensive sampling with the expense of sampling and the practicality of actionable management units.

Grid sampling is a strategy to learn more about your soil. Sampling from the exact same locations year-over-year provides powerful insights into the true impact of variable rate management, but that can be a challenge for manual sampling. How you take the samples themselves can influence the data; a human might not probe exactly 7 in. of soil at each location or lose count and be inconsistent in how they combine samples to send to the lab. Repetitive, physically taxing tasks that require precision are ripe for automation.

Two of our 2019 PFR summer interns helped to illustrate this issue with their summer learning projects.

The map below shows a 50 ft. x 50 ft. plot where one of our dedicated interns took soil samples based on a 5 ft. x 5 ft. grid. That means taking 100 soil samples in an area smaller than a typical front yard. Those samples revealed pH levels that ranged from above 7.8 to below 6.8 – that’s a ten-fold change in the acidity of the soil. As discussed on page 2, availability of all other nutrients is dictated by pH, so micromanaging your soil might have a big impact.

So how do you practically incorporate soil sampling on your farm? Two companies with ties to Beck’s offer automated soil sampling solutions, taking the grunt work out of grid sampling.

Rogo CEO Troy Feichter was watching someone haphazardly collect soil samples on a neighbor’s farm and thinking about unexplained variation in his own soil test data, when he had an idea for an automated, autonomous soil sampling system. He and President Drew Schumacher offer services directly to farmers, but primarily through retailers, co-ops, and agronomists in order to add value to farmers. Rogo is headquartered in West Lafayette, Indiana, and their research and development takes place inside Beck’s dealers Josh and Troy Furrer’s shop.

Beck’s customer Jim Case in Delaware County, Ohio, designed, engineered, and built SoilHawk in response to his needs on his own farm. Once the engineering was complete, Jim started offering his services to other farmers in the community. SoilHawk is unique in the marketplace because it removes the residue from the soil surface prior to taking the core. The lightweight aluminum trailer can be pulled across a farm by a truck or ATV even in wet soil conditions.

In a study by Beck’s Practical Farm Research (PFR)®, we compared the repeatability of humans versus Rogo’s robot by having them each sample a field three times in the same day. The soil nutrient results varied 14% for humans and only 5% for Rogo’s robot, both of which include lab error (+/-2.5%). Rogo’s robot eliminated approximately 10% error incurred simply by human field sampling. Half of the error reduction was through sampling the exact same location, and half was from sampling to precisely 7 inches deep with a high-speed auger.

That may not sound like a big deal, but using Tri-State recommendations, human sampling resulted in a fertilizer bill that ranged $22/A. up or down (25%), but Rogo reduced the swing down to +/- $9/A. (10%), on an $85/A. fertilizer bill for P, K, and lime. Who wouldn’t want to eliminate $13/A. of error on a fertilizer bill?

Ultimately, more accurate soil test data, paired with precise application strategies, will help farmers increase yield, budget fertilizer costs, and reduce the amount of fertilizer potentially lost to the environment.

Your local Beck’s representative can help you get started on a soil testing regimen to improve efficiency on your farm. For more information on these two systems, visit rogoag.com and soilhawk.com.