Farm where every drop of water is precious and you get creative. You pay attention and look for ideas in unusual places.
That's how Johnny Andrews found the latest water-saving opportunity on the Dos Palos, Calif., cotton farm he runs with his son, Jonathan. It is an aboveground drip irrigation system, which he saw while traveling in Israel.
"When I saw it, I thought, hey, that could work on our place. In Israel, they're making five to six bales ofcotton an acre using it,” Johnny says. "So when I got home, I started figuring out how to do it and got lined up with a supplier. I'm trying to make more money and save water too. That's the name of the game.”
The two put in a 24-acre test field in 2007. The results astounded them.
"It averaged a bale per acre more than that field had ever done. It used 1.6 acre-feet of water compared to the 4 to 4.5 acre-feet of water we normally use in furrow irrigation. In 2008, it made three-fourths of a bale more than the historical yield of that field, and the water efficiency was about the same as the year before,” Jonathan says.
"The first year, we averaged 3.5 bales per acre on it. This isn't a great field, by any means. It's a real alkaline piece of ground with a lot of soil types. We just started farming it in 2007. Its best yield ever was 2.5 bales per acre.”
In addition, the aboveground system reduced input costs. They got by with 90 units of nitrogen (N) on that field, rather than the 140 units required on other fields.
"There's no leaching with drip, so you use less fertilizer. It's a nice savings,” Jonathan says.
Farming in dry country makes water a priority for the Andrews family. In the semiarid San Joaquin Valley, crops get nearly all their water from irrigation, rather than rainfall. It mostly comes from snowpack in the Sierra Mountains, which has been in short supply for a while. Until rains this past December, the weather had been even drier than usual. Top that with a federal judge's ruling to close crucial irrigation pumps to protect an endangered species of smelt, and many of the state's farmers faced severe water shortages in 2008 that idled considerable acreage.
Irrigation makes farming possible in this area. Without it, crops could not grow. About three-quarters of California's cotton fields are furrow irrigated. Most of the remainder is flood irrigated. Center pivots water a small percentage. Drip irrigation is, as yet, just a small but growing blip.
The Andrews family is luckier than many Californians. Their water rights are grandfathered thanks to a contract exchange with the state in the 1960s guaranteeing their supply as long as water is available. That doesn't mean they take water for granted, particularly in a time of extreme drought like their area experienced in recent years.
"We're fortunate to be in this area. Our water is not that expensive. We're not on a federal contract, and we built and paid for our canal,” Johnny explains. "But we can't waste it. We do everything we can to be efficient with our water usage.”
The surface drip system's emitters are spaced 24" apart, although the family is experimenting with 6" spacings, as well. Emitters used in the first year were too small, which resulted in some plugging-up problems. The Israeli manufacturer, Metafin, replaced the entire supply of drip tape.
Father and son aim for precise, almost drop by drop, water application. They use a pressure chamber test to monitor each cotton plant's water usage in order to keep it at optimal production.
"We want to keep it going so it reaches its potential,” Jonathan says.
To keep on track, he charts the cotton plants' growth. "We measure daily growth and compare that with the optimum growth curve for cotton. We keep track of the water uptake. Then, we send that information to a guy in Israel and he e-mails back how much water we need to be putting on the field,” Jonathan says.
"He created this growth curve after 12 years of research on cotton. It takes into account how much the cotton grows daily and how much water it's using, and he created the optimum growth curve. Our goal is to keep a level curve. We want there to be no drops down,” Jonathan says.
The simplicity of the system impresses the two. So does the cost. "There's no expensive drip line or filters. You can use the tape for six years. We have about $300 an acre in it, so the cost isn't high,” Jonathan says.
"We inject fertilizer through a 500-gal. pump. It cuts fertilizer cost 30%. With N costs being what they are that's a big deal,” Johnny says.
Another plus, the men say, is that the field never gets too wet, so it is always available for spray applications.
That little 24-acre field became quite a curiosity in the community.
"We almost had to sell tickets, so many people wanted to see what the crazy people were doing over here. We just about had them lined up out here. There was so much interest in it, it was hard to fathom,” Johnny says.
For 2009, the two are installing 400 acres of subsurface drip, a new idea for them, and 200 acres of surface drip.
"Buried drip is becoming popular. It provides a cost savings, increased production and a water savings. We want to conserve water. We're trying our best to do our part. We're playing with this now so if the time comes when we have to do it, we'll know what to do,” Jonathan says.
"I'm going to be proactive. If we monitor it right and use the least amount of water the plant needs and put the plant in optimum condition, then it's a win all around. Even where there's sufficient water, farmers need to try to conserve. If you conserve and still increase yields, then what do you hurt?” Johnny says.
You can e-mail Charles Johnson at firstname.lastname@example.org
- February 2009