AGRICULTURE TECHNOLOGIES 2016
A monthly supplement to The Delmarva Farmer
Farmers consider subsurface drip irrigation’s benefits, drawbacks
Increasing efficiency and return on investment are key factors farmers consider when adopting new technology.
Subsurface drip irrigation shows promise on both points, but farmers in the Mid-Atlantic are slow to adopt the technology.
One of the reasons is because water supply in this region isn’t a major concern right now.
According to USDA-NASS data, utilization of subsurface drip irrigation has increased 89 percent over the past decade.
An overwhelming majority of that SDI land area is located in just 10 states, primarily in the south and west where water conservation is a key issue.
Water conservation isn’t the only potential benefit of SDI, though.
Matthew Taylor is the co-owner of Root Rain Irrigation in Preston, Maryland. He says SDI can save producers on energy costs, reduce use of fertilizers and herbicides and improve field efficiency.
“The SDI systems we’ve installed have been very successful. We see increased efficiency across the board, especially increased crop nutrient uptake.”
Taylor and his brother in law, Nate Wolf, started the company three years ago, after hearing about the technology.
“It was an innovative business that we could start together and grow,” said Taylor. “We both came from farming families and this was an opportunity to bring in a source of income to our farms and to be on the cutting edge of agriculture.”
Root Rain Irrigation is a dealer for Eco-Drip, a Texas-based company that has been working with SDI technology for more than 30 years. Texas has the second largest SDI land area in the United States, primarily for growing cotton.
While the technology has been growing in other states, farmers in the Delmarva region are just starting to take notice of the potential benefits. In the past three years, Root Rain has installed a handful of systems. Taylor said farmers are slow to adopt the technology in part because of a fear of the unknown.
Dorchester county farmers, Jeff and Terri King were willing to take a chance, though.
They had Root Rain install an SDI system on 10 1/2 acres three years ago and have plans to install more acres of SDI in the near future.
“Farmland is hard to come by. We decided we had to make more of what we already have. Some land is hard to irrigate. We heard about subsurface drip irrigation and thought it was a good fit,” said Terri King.
King said pivot irrigation wasn’t viable for the parcel where they installed SDI. She said, the best they could hope for was 150 bushels of corn per acre.
“We’ve more than doubled that. It’s exceeded our expectations,” King said.
They run two center pivots on the same farm.
She said the parcel with the subsurface drip irrigation uses 50- to 60-percent less water.
SDI research has been taking place in Delaware and Maryland under the direction of James Adkins, an Associate Scientist and Irrigation Engineer for the University of Delaware Cooperative Extension.
“SDI presents an opportunity to irrigate fields that would previously be uneconomical to do so,” Adkins said.
The irrigation specialist said subsurface drip irrigation can work in fields where pivots can’t such as small parcels of land, rectangular or odd shaped fields and in fields that have obstructions such as roads or buildings.
On a larger scale, though, Adkins said it’s often cheaper to irrigate with a pivot. He said SDI costs about $1,800 to $2,000 per acre. His research doesn’t directly compare SDI to pivot irrigation, but anecdotally, he said there doesn’t appear to be a correlation between irrigation method and crop yields.
“It’s more a function of individual management practices,” he said, and the ability to fully irrigate corners or otherwise dry areas.
Adkins said other challenges that SDI presents are leaks, which can be difficult to identify and repair. Insects and burrowing rodents can damage underground irrigation systems. Longevity, he said, depends on water quality.
“It’s important to have an excellent filtration system,” he said.
Taylor said it’s a misconception that subsurface drip irrigation prevents a farmer from working the ground over top of an SDI system.
“System design is key,” he said. The recommended depth for drip tubing is approximately 12 inches below the surface. Row spacing can vary based on the individual farmer’s preference and ability to achieve uniform irrigation.
Perhaps the biggest hurdle for producers, though, is the initial cost of an SDI system.
USDA NRCS offers financial assistance for irrigation practices, but not specifically for subsurface drip irrigation. While water availability and use efficiency are concerns, the priority areas for Maryland NRCS are water quality and soil health, said Genevieve Lister, the agency’s Public Affairs Specialist.
For the Kings, their SDI system is well on its way to making a return on investment. In addition to the yield increases, they’ve been able to decrease their fertilizer inputs. They see this as both a cost savings and an environmental benefit.
With the exception of their starter fertilizer, the Kings deliver all of their crop’s nutrients through the drip tubing.
“We have the ability to spoon feed nutrients directly to the root zone. We’re not putting fertilizer down all at once. There’s a small amount that trickles into the water supply. The crops are constantly taking it up,” said Jeff King.
Root Rain Irrigation recently partnered with Willard Agri-Service to utilize liquid fertilizer in subsurface drip irrigation systems.
“Willard is the premier liquid fertilizer dealer,” said Taylor. “We encourage our customers to use them on their programs.”
Taylor said he sees a huge potential for SDI to benefit organic growers. His company installed a system for Perdue Agribusiness in Hurlock, Md.
“SDI keeps the surface of the soil dry which suppresses weed germination. It also allows farmers to cultivate any time they want. It’s very in tune with organic principles,” said Taylor.
Adkins said there are still a lot of questions to answer about the potential SDI holds for farmers in the Delmarva region.
“The jury is still out on whether or not SDI is a conservation tool. Some of our research is trying to quantify any nutrient use efficiency there may be for the Bay model. In good time, we should have an answer for that,” said Adkins.
“I would recommend it to any farmer out there,” said Jeff King. “There are a lot more benefits than just water savings. We’re using less electricity and less fertilizer. It may be more expensive on the front end, but it’s worth it for the cost savings over time.”