To anyone unacquainted with agriculture in the western states, putting sulfuric acid on a crop might sound like agronomic suicide. Then again, who would have imagined 20 years ago that tractors would someday drive themselves with the aid of satellite guidance? As science and technology have advanced, so, too, has agriculture.

According to Tim Lowry, the West Coast sales representative for Agri-Inject, the practice of injecting acids to irrigation water to balance high water pH levels has been going on in parts of California and the West for at least 30 years. However, it’s only been in the past five to seven years that the practice has been moving east.

Already, parts of Texas and certain areas on the East Coast have found that using an Agri-Inject pump to inject acid into the irrigation water has helped increase both water infiltration and nutrient availability.

It all started back in the ‘70s when MCDS (Moncarbamide Dihydrogen Sulfate) started to find its way into the golf and agricultural market. Labeled as 15-0-0-16s, 49% sulfuric acid, it was originally targeted to the golf industry, since that’s where the problems were most prevalent. That’s due in part to the inability to disc or plow turf soils.

As a general rule, soil mimics the water that runs through it – alkaline water makes alkaline soil. Water with high bicarbonates (HCO3 -ion) attracts calcium ions, forming Ca (HC03), which means large amounts of bicarbonate ions in irrigation water will precipitate calcium. When high bicarbonate water reaches the soil, the calcium can be removed from the soil particle. Sodium can then take the calcium's place at a rate of two sodium ions to every one calcium ion. In this way, a calcium-dominant soil can become a sodium-dominant soil by the use of high bicarbonate irrigation water.

DCDS (Dicarbamide Dihydrogen Sulfate) 28/27 (28-0-0-9, 27% sulfuric acid) is well known in the golf industry for being the perfect nitrogen. The 28% nitrogen is more of a control-released nitrogen, which works as an oxidant, adding oxygen to the water and to the soil. What truly makes this formulation so unique is the controlled release of nitrogen. In effect, it’s an acidic, it’s an oxidant, it is root and foliar absorbed, it’s stable in saline water and has an impact on disease and microbes.

As Lowry relates, the obvious reason for using an Agri-Inject system to add an acid formulation to irrigation water, is to reduce the pH in water. However, the better reason is to gain the benefits that come with acid injection. The practice not only alters the chemical composition of the water, but reduces the sodium adsorption ratio and creates better water percolation. Acid injection can also increase fertilizer performance, enhance the effectiveness of alkaline sensitive pesticides and improve overall soil quality.

“One to two decades ago, it was more common to use acid injection just to balance out the pH and to reduce the problems with calcium build-up in like the sprinkler heads,” Lowry says. “However, research has since shown us that there are other benefits.

“Your average water pH in some of the West Coast states runs from the mid to high sevens to an average that falls between 8.2 and 8.8 in some areas,” he explains. “So they try to buffer it with a variety of different acid sources,” he adds, noting that there are now a number of different manufacturers offering everything from urea-based acid to phosphoric-based acid.

Lowry notes that even though most Agri-Inject units can be used for acid injection, particularly the fertilizer injection units, he says it’s always best to have the pump converted to “acid ready” by having the factory change out some of the components with acid-resistant alloy 20 material.

“The 316 stainless steel that Agri-Inject uses on the conventional pumps will hold up for a while with acid,” he relates. “But Agri-Inject is not into building units for the short term. Our pumps are built for long-term usage, so we like to do it right from the start and that includes installing alloy 20 heads.”

Lowry says that as water restrictions becomes more prominent and various areas experience drought, affected producers are realizing that they can get more bang for their buck by adding an acid blend to the irrigation water, particularly if the water or soil is high in pH.

“If you look at California, for example, the only way you can offset a reduction of water is to make your water perform better for you,” he relates. “If you acidify the water, you get better water filtration and a reduction in the sodium adsorption ratio. With these extra benefits working their way into your soil, you will also start to see a better uptake of the fertilizer that you are currently using.”

Of course, the only way to know if acid injection will be beneficial to your operation is to have a professional determine the soil pH and perform a water analysis to determine the level of bicarbonates and sodium. In a growing number of cases, adding an acid formulation to the irrigation water — as crazy as it may sound — could provide unforeseen benefits.


To learn more about Agri-Inject or acid injection, call 970-848-5336 or 800-4-INJECT, or view the full line of products at www.agri-inject.com.