Will Wetting Agents Move From Turf to Crops?
CHANGES IN TECHNOLOGY
Wetting agents prevent the soil from becoming hydrophobic in the first place by reducing surface tension and enhancing cohesion or the attraction of water molecules to solids. Similar to a good degreaser detergent, early wetting agents stripped the organic coverings off. However, they were often harmful to plants, noted Todd O'Connell, foundation manager, Exacto.
Todd O’Connell "By the mid 1980s, surfactants were found that worked reasonably well and didn't harm turf," said O'Connell. "Since then they have continued to improve, adding value with formulations that last longer, drive root systems deeper or more shallow. Some are designed to be applied with pesticides and some injected into irrigation systems."
It is irrigation injection products that Exacto is currently exploring. "We are working with Valmont Industries, a major irrigation equipment manufacturer and an independent field research firm to evaluate the impact of a wetting agent injected through the system," explained Sexton.
Frank Sexton is the product manager coordinating the irrigation research. "We are looking at water efficiency, comparing 0.75 inch of water per week with wetting agent, water with no wetting agent and 0.375 inch of water with wetting agent on soybean under a center pivot," he explained. "Each plot is a wedge of the pivot of about 6 1/2 acres that we will take to yield."
Frank Sexton Sexton is hoping this summer's trials will lead to more and expanded trials involving the patent pending compound polymer. Expectations are that the wetting agent/soil surfactant in combination with a long-chain polymer will not only increase infiltration and air exchange and reduce crusting, but will also hold on to water in the soil.
"We hope the soil surfactant will drive the moisture down deeper and then hold it longer," said Sexton. "If reduced water works as well as the full 0.75 inch, it means water and energy savings."
LEARNING FROM AUSTRALIA
Although wetting agents have not been accepted in American row-crop agriculture, that's not the case in Australia, noted O'Connell. There, equipment is available for application with seeds as well as with transplants in high value cropping.
"They understand drought in Australia and the use of wetting agents," he said. "Specific products need to be applied for a specific purpose at a specific time in the season if it is going to be cost effective for the end user. Application isn't simply drenching a field and crossing your fingers."