Farmers constantly seek more 'crop per drop'

Issue Date: February 18, 2009
Kate Campbell

Stanislaus County almond farmer Merlyn Garber examines a soil moisture sensor at the 2009 World Ag Expo in Tulare. The device, one of many water-saving technologies featured at the show, allows farmers to monitor the wetness of their soil so they know when and how much to irrigate.

When irrigation specialist Rick Mallory sets off for work on San Joaquin Valley farms, he's headed for a world of computers, spreadsheets and complex math equations. He uses these tools to fine-tune the H2O delivered to crops on thousands of acres, wringing the most benefit from every drop.

"Our evolution to the sub-surface drip irrigation system we use today has taken place during the past 20 years," Mallory said. "We haven't made any big investments in irrigation equipment lately because we're already pretty high tech. But we do upgrade as new technology becomes available."

Lately, however, Mallory said he's seeing a dramatic increase in the rate other farms are investing in new technology, including sub-surface drip irrigation, especially in water-short areas like the western San Joaquin Valley. And, he points out there also has been ongoing investment in irrigation technology as it has been improved—better emitters, valves, gauges and management.

"Ten years ago I only knew of one grower who was using sub-surface drip on processing tomatoes. But today, because sub-surface drip has proven to be the way to go because of increased crop yield and quality, more growers have invested in the technology," Mallory said.

"It's a chicken and egg thing. With more growers using the technology, with more acres involved, companies are updating their computer programs, soil monitoring technology, metering systems—all of which is making it easier to apply the technology, do more with available water and calculate a return on investment," he said.

But, new irrigation technology can be expensive, he said, and it also requires a whole new skill level for employees.

"We're finding new irrigation products all the time, at farm shows and in trade publications. And we're finding ways to integrate emerging technology, like GPS (global positioning systems), which has really come into its own in the past four or five years. All these things make it easier for us to do the job, but at a cost."

Experts suggest California farmers and ranchers have invested hundreds of millions of dollars in irrigation technology in recent years, and there's general agreement that the pace of investment and technological advancement is increasing. The 2003 Irrigation Survey, a supplement to the U.S. Census of Agriculture, indicates that California farmers with irrigated land invested more than $217 million in irrigation equipment that year. The figure includes investments in facilities, land improvement and computer technology.

A new five-year survey is being conducted now that will reflect investments in irrigation technology for 2008 and document the scope and rate of investment in recent years. The survey has been mailed to 35,000 producers nationwide. Survey results are scheduled to be available online Nov. 30.

For a longer look, the California Farm Water Coalition compared the amount of water applied to California farmland and the amount of crops produced in 1967 and 2000. The coalition's analysis shows that while agricultural water use is almost unchanged during the past 40 years, crop production figures have increased dramatically.

In 1967, the state's farmers applied 31.2 million acre-feet of water on their irrigated cropland. In 2000, that figure was 34.2 million acre-feet, an increase of 9.6 percent. During the same period, acres planted increased about 8 percent.

But production volume for field crops, fruit and nut crops, and vegetable and melon crops jumped from 35.8 million tons to 67.7 million tons, an increase of 89 percent.

"It's clear California farmers are using water much more efficiently than they did previously," said Mike Wade, the coalition's executive director. He added that analysis also indicates that the value earned for crops has not kept pace with production levels—margins are thinner and water is getting more scarce.

A coalition survey of irrigation companies and suppliers shows that between 2003 and 2008, California farmers invested more than $1.5 billion on drip and microsprinkler irrigation technology. About 1.3 million acres had high technology irrigation systems installed during the period.

Wade said the coalition also plans a new survey of growers, "to find out what leads farmers to install and upgrade irrigation systems and, equally important, what's preventing this kind of investment."

Charles Burt, an irrigation expert with Cal Poly, San Luis Obispo, agrees that better data regarding investments on irrigation technology would be helpful, but he says from personal knowledge that in recent years irrigation equipment dealers have had some of their best sales results.

And, as head of the university's Irrigation Training and Research Center, he said students who have majored in irrigation technology and soil science often are hired before they graduate—another indication of farmers' interest in the technology and the growing need for trained personnel to operate it.

In addition to installing on-farm irrigation technology, many farmers engage in other kinds of conservation practices, for example use of cover crops, minimum tillage, water recycling and mulching.

"Let me put the decision this way," said farmer Ted Sheely of Lemoore. "When we converted to underground drip tape we saved about a tenth of an acre-foot of water per acre, but we also increased crop yield more than 20 percent. That's were the business economics come in."

Sheely says a farmer can make the conversion and pay for the cost of installing the system in four or five years.

"The high cost of water, however, isn't something we can escape. We use drip on tomatoes and all our permanent crops, pistachios and winegrapes. We provide the precise amount of water we want," he said. "On the other hand, it doesn't matter how much drip equipment you put in, if you don't have water to send down the line. Right now we don't have enough water to supply all the high-tech irrigation systems that are out there."

Information on the U.S. Census of Agriculture Irrigation Survey is available online at

(Kate Campbell is an assistant editor of Ag Alert. She may be contacted at

Permission for use is granted, however, credit must be made to the California Farm Bureau Federation when reprinting this item.