By Frank Giles
The Southeast Regional Fruit & Vegetable Conference, held in Savannah, Georgia, in early January, drew specialty crop growers to learn about what’s new in production, products and technology.
While precision agriculture in specialty crops has generally lagged behind traditional row crops in terms of adoption, new applications and advancements are catching on. During the conference, a precision agriculture breakout session was well attended, illustrating the interest.
PUSHING PROGRESS
During the seminar, a session featured the new Institute for Integrative Precision Agriculture, which was announced last year by the University of Georgia (UGA). The institute aims to harness the tremendous amounts of data that precision agriculture tools generate to allow management decisions that will improve growers’ productivity and profitability.
According to UGA, precision agriculture maximizes yields through data-driven decision making enabled by technologies and tools such as soil moisture sensors, drones, satellite imagery and robotics. Integrative precision agriculture expands the range of opportunities for optimization using artificial intelligence, machine learning and big-data analysis.
Rather than focusing exclusively on row crops, the institute will address a range of commercially important sectors that includes poultry, peanuts, cotton, fruits, vegetables and controlled environment agriculture. What is learned will benefit specialty crop producers beyond the borders of Georgia.
GRID SOIL SAMPLING
One of the most basic ways specialty crop growers can dip their toes into the precision agriculture waters is through grid soil sampling to enable variable-rate applications of fertilizer.
Daniel Jackson, director of the UGA Agricultural and Environmental Services Lab, gave a presentation on soil sampling strategies in fruit and vegetable production. Grid sampling requires more samples to be pulled and analyzed — for example, 10 samples per area of unit versus two. Jackson said that’s obviously going to cost more money, but there are opportunities to see a return on investment.
Jackson said research shows the optimal size of a grid is about 2.5 acres from which to pull samples but added that’s probably not practical from a cost standpoint. Grids in the 5- to 10-acre range are more feasible for most specialty crops growers.
“Where do I see (grid sampling) and variable-rate technology fitting into specialty crop production is lime management. I see that as the low-hanging fruit, and it’s the reason a lot of growers are beginning to use it,” Jackson said.
“If you have large variability (of soil type) in a field, that is the whole objective of this technology. If you have a field that is not very variable, it is not going to offer much of an economic advantage. But if you have a field that has a lot of variability, it will pay off.”
ADDRESSING NUTRIENT DEPLETION
Jackson said the technology also could be used to address late-season issues in fields where nutrients might be depleted. “If you are seeing what appears to be a weak area in a field, you could go out and take a leaf sample. With that information, you could easily create a nitrogen variable-rate application map for the areas that are weak versus across the entire field,” he said.
For the more sophisticated user, there are aerial imagery software products that can identify areas that have potentially depleted nutrition in spots. Prescription application maps can be developed from those tools.
EASE OF USE
Finally, Jackson said there’s multiple companies that provide controllers, which allow for variable-rate applications. He added the technology is much more open-sourced these days, making it easier to jump back and forth from different technology brands to accomplish the job. For example, a grower can create the variable-rate prescription with one brand but make the variable-rate application using a controller of another brand.
“The technology is much more user friendly than earlier days, and there are resources (consultants, retailers, etc.) available to help you use it effectively,” he said.