Other products, including humic acids that are supposed to change soil chemistry and improve nutrient uptake are equally unimpressive. “Humic acid occurs naturally in the soil,” he said. A three-year study on four crops showed “no economic response.”

He singled out Avail, promoted as a “progerminator” that would produce equal yields with about 25 percent the standard Phosphorus fertilizer rate. “The product did fine,” McFarland said, in North Carolina tests. “But it costs the same amount per acre (as the standard fertilizer rate).” He said reliance on the material would result in “mining the soil) of nutrients. Eventually, producers have to add more phosphorus.”

“These products have appealing sticker price tags,” Corriher said, “but the economics may not add up.”

She recommended trying no more than a small amount on limited acreage to evaluate a product. “Traditional fertilizers produce the best yields,” she said. “We see a significant difference between traditional fertilizers and snake oils.”

Research has shown average yields with the “alternative products” at 900 pounds of forage per acre compared to 3200 pounds per acre with traditional fertilizers. “We see little difference between these products and untreated check plots,” she said.

McFarland recommends producers ask for more information before using these “miracle” products. “Insist on scientific research from a credible source,” he said. He said an Internet search might not provide reliable information. “The first few sites will be marketing sites,” he said.

“Request local data and conduct your own scientific tests over a uniform area, multiple plots with and without the product. Replication is a key.”

He said plots should all be managed and harvested similarly.

rsmith@farmpress.com