By Jeanine Moyer for AgInnovation Ontario
Guelph – Climate change is making Ontario’s farmers look carefully at water conservation and efficient use.
Agriculture is a significant water user in the province, and after experiencing drought-like growing conditions in 2012 and watching regions in the United States deal with severe water restrictions, Ontario agricultural researchers are working to find new cropping methods to use water as efficiently as possible.
In Ontario, crop irrigation systems are most commonly used on fruit and vegetable crops; less than 5,000 acres of field corn are currently irrigated.
However, irrigation is essential to producing maximum corn yields in parts of Ontario, leading researchers and irrigation experts to team up to find new ways to irrigate crops in a more water conscious and efficient manner.
The result is a new-to-Ontario below ground crop watering system, Subsurface Drip Irrigation (SDI).
Since 2013, University of Guelph Plant Agriculture professor Rene Van Acker has led a research team studying this low-pressure, high-efficiency irrigation method that uses buried polyethylene drip lines to bring water and nutrients to crops.
The team has been testing the system in corn fields, since corn requires more inputs like water and nutrients than other Ontario-grown field crops.
“Traditional crop irrigation methods are very labour intensive with inefficient water and energy use,” says John O’Sullivan, also a professor in the University of Guelph’s Plant Agriculture department and the on-site project manager of the SDI research.
O’Sullivan explains customary irrigation systems use aluminum pipes laid above ground and across fields, using overhead water sprinklers to deliver water to crops.
Mobile sprinklers are also popular, but use a lot of energy and of the irrigation water applied, as little as 50 per cent is actually used by the crop.
“SDI can deliver water with an efficiency of 95 per cent or higher and keep corn root zones closer to optimum soil moisture and maximize fertilizer utilization,” says O’Sullivan.
The team has proven SDI is the most efficient system with water savings of 25-50 per cent when compared to traditional overhead water irrigation.
Burying the SDI water lines instead of sprinkling water onto the crops immediately boosts water use efficiency by eliminating water evaporation from above ground sun and air exposure.
Unlike other drip irrigation systems where water lines lay flat on the ground surface, SDI drip tapes are buried 14” in the ground.
Doubling the efficiency of the new irrigation system, crop nutrients, or fertilizer, can also be added to the water pumping through the sub surface irrigation lines.
This allows farmers to deliver exact amounts of fertilizer to the crop throughout its growing stages. And since nutrients are applied right at the plant’s root level, very little is left unused, which reduces the chance of fertilizers leaching into the environment.
“It’s like spoon feeding our plants,” says Gary Csoff, Technology Development Representative with Monsanto Canada Inc., who points out the ability to apply nutrients through the SDI system also maximizes the crop’s yield, quality and the farmer’s economic investment in costly crop nutrients.
“This new crop production technology will maximize productivity per acre while protecting our environment,” says O’Sullivan, adding that a one per cent adoption rate of SDI by Ontario farmers would generate an additional $10 million in farm gate sales through increased yields and more efficient nutrient management.
SDI research has been funded by Farm and Food Care Ontario’s Water Adaptation Management and Quality Initiative.
The research team has also been awarded funding through the University of Guelph’s Gryphon’s LAAIR (Leading to Accelerated Adoption of Innovative Research) program to continue testing and conducting demonstrations to farmers interested in adopting this new technology. The Gryphon’s LAAIR is supported through Growing Forward 2, a federal-provincial-territorial initiative.
“This is an out of the box approach to irrigation that has stimulated a lot of thought and discussion,” says Csoff.
The SDI research team also received input support from Peter White, Irrigation Research Associate at Simcoe Research Station, Todd Boughner of Judge Farms in Simcoe, and Vanden Bussche Irrigation of Delhi.