http://westernfarmpress.com/citrus/citrus-freeze-0114/

Battling citrus freeze vulnerability

Jan 14, 2010 10:47 AM, By Dennis Pollock, Contributing Writer

Nick Hill was preparing to greet a customary holiday guest — freezing cold temperatures that could harm his citrus grove in the Orange Cove area of the San Joaquin Valley.


NICK HILL, right, who manages citrus and
other crops for Greenleaf Farms Inc., talks
with Noel Sergent, owner of Noel Sergent
Irrigation, Sanger, who is putting in a
cement slab on which large propane tanks
will be installed.

His reservoir was filled with the water he would need to help keep temperatures up and help him avoid becoming a casualty if temperatures dived – as expected within days – into the 20s.

And his tanks were filled with propane that would be used to run some of his wind machines to pull warmer air into the groves.

Hill, like other growers, learned a bitter lesson about two years ago when several days of low temperatures drained propane supplies and left many citrus growers without the needed ammunition to battle the freeze.

In the wake of a January 2007 freeze that resulted in a billion dollar loss to California citrus, growers have boosted their storage capacity and added plumbing to make it easier and quicker for trucks to deliver the fuel.

“Time is critical,” Hill said.

Hill has already replaced leased 500-gallon tanks used to power a single machine with 1,000-gallon tanks he purchased. He added piping so that the tanks could be moved from beside the wind machine to main avenues through his groves.

And he’s not done yet. This year, Hill is putting in a cement slab where he will place two 3,500-gallon tanks for additional storage.

“The growers have been proactive about this thing,” said Dwayne Cardoza, a raisin grower and sales manager for a propane supplier in Fresno, Windmill Propane.

“Before, there were tanks in the middle of the orchard,” Cardoza said. “Imagine if it’s foggy and dark and a driver is out there trying to find the machine. It’s an ugly situation. I know of a grower who took out a whole row of trees to make the tank accessible.”

Cardoza said Delano-based Paramount Citrus, which farms about 30,000 acres of citrus, has put in what are called “community systems,” tanks as large as 20,000 gallons and plumbed to reach wind machines throughout a grove from a single location.

Hill said some growers, including him, are considering getting their own used “trap wagons,” trucks with tanks to move the fuel throughout the groves that they know like the back of their hands.

Propane supplies appear to be adequate, said Lesley Brown Garland, president and CEO of the Western Propane Gas Association.

“It has just now gotten cold,” Garland said, noting a significant difference between a pre-Christmas cold snap that hit the Valley this year compared to the mid-January freeze in 2007. “There’s a tremendous supply right now, and we don’t expect a supply disruption.”

Cardoza said he had friends of 30 years who were begging him to bring them gas. “But there was just not enough equipment for a major freeze, even with all of us.”

In 2007, California Citrus Mutual, a 2,000-member citrus trade organization in Exeter, worked with the state Office of Emergency Services and the California Highway Patrol to bring more propane to the region. Lingering cold lasted for several days.

Of 12,000 wind machines in the Valley, 7,000 rely on propane.

Hill has been purchasing more diesel powered wind machines lately, moving away from propane, but the diesel machines cost about $3,000 more.

Hill has also been moving to automatic wind machines that have sensors in the groves: “If it reaches 29 degrees, it will turn on, and if it moves back up to 31 or 32, it will shut itself down with no adverse effects to the engine. We have almost 40 automatic machines that cost an extra $2,500.”

He has a total of 95 wind machines to protect about 1,200 acres of specialty citrus that includes lemons, minneolas and cara cara navels. Twenty-five require propane. The rest are powered by diesel or electricity.

Hill estimates his costs for frost protection – including uses of both wind and water – at about $200 an acre.

The lemons are the most sensitive to cold. “If it gets to 27 for more than a couple hours, they can be damaged,” he says. “Oranges can take that temperature for up to five or six hours.”

It’s one reason he has crews out in his Lisbon lemon grove picking on a Saturday as word spreads that an arctic wind mass is about to sweep into the Valley on the heels of a rain storm.

When the cold snap hit, and Hill was able to keep temperatures no lower than 26 or 27 degrees. There was little warm air aloft that night, he said, but water helped warm the groves.

The next night, there were some 24-degree readings in outlying area. But wind machines worked better, pulling down warmer air from above to raise temperatures five or six degrees.

By Wednesday night, temperatures warmed as a cloud cover moved in. Wind machines were started earlier – at 8 p.m. – but were shut down by midnight.

Hill’s citrus crops appear to have survived that cold snap. And most of the industry likely also fared well.

Joel Nelsen, president of California Citrus Mutual, said there may have been isolated pockets of internal damage. And it’s expected some exterior damage will result from ice marking because fruit was wet when the freezing temperatures hit after Monday’s rain.

“That won’t show for a few days,” he said. “We’ll have to figure out where it happened and how much.”

Only by mid-February, Nelsen said, will growers be able to lower their guard against freezing temperatures.

Ice marking is easier to spot than internal damage, Hill said.

“But the streaking can be as bad, knocking the fruit off grade,” he added.

The freeze watch is far from a new game for Hill, who has been dealing with such matters for 25 years. He’s accustomed to sleepless nights, awakening to an alarm at his home between Reedley and Dinuba that tells him the temperatures have dipped to dangerous levels. Sometimes he sleeps fitfully, waking to check the thermometer even if the alarm does not sound.

“Or if I hear a wind machine, I’m awake,” he says.

When temperatures dive, he alerts others and then it’s into his pickup, which has a thermometer that tells him what the temperature is outside as he drives the groves.

He recalls the 1990 freeze when everything, even including some trees, was wiped out. Then came 1998 when some fruit survived. “But there was some fruit that year that shouldn’t have been shipped,” he said.

That soured some consumers, and the industry in 2007 took painstaking steps to avoid freeze-damage fruit finding its way to supermarket shelves.

This year, as Hill and others braced for the freeze, there was another concern. A three-year drought has not helped. The ground holds less water than customary this time of year. Trees are stressed, Hill said, and the movement of air aloft has been slight.

Some in the California citrus industry, after weathering their first serious brush with Jack Frost, take some solace in a notion akin to the adage that “what doesn’t kill you can make you stronger.”

As he walked the groves before the freeze, Hill said the crop was already made less vulnerable by what had been some chilly nights. The cold nights helped put trees into dormancy and make the fruit better able to withstand the cold.

“It makes it stronger,” he said.