California grower Brian Blackwell believes the above-average rainfall and cool temperatures this spring are a double-edged sword for the 2010 Western pistachio crop.

“We don’t know how many (shell) blanks we’ll have due to the lousy weather during bloom time,” Blackwell said. “We had plenty of winter chill hours, but the problem was the unusual high rain and wind events. We don’t know yet if the crop was adversely affected by the weather. Kernel development should begin in early July.”

Blackwell grows pistachios in Kern and Tulare counties in the southern San Joaquin Valley. He owns and operates his own pistachio farm, Blackwell Farms. Blackwell also wears the hat of president of the Blackwell Farming Co., where he manages pistachio orchards for other landowners.

Blackwell is chairman of the Western Pistachio Association.

It is too early to predict the exact size of the 2010 California pistachio crop. Yet Blackwell predicts an average crop; perhaps in the 350-million-plus pound range.

The 2009 crop initially looked promising – in the 400-million pound range – until spring weather tempered yields.

Kern County received more rain this spring than the last five to six years, Blackwell says. About 7 inches fell in the Bakersfield area. The area has averaged 3.5 to 4 inches in the spring annually over the last five years.

“We received almost double the rain, but it was the timing of the rain which created problems,” Blackwell said. “The rain started in April and fell about every 10 days. In some fields up north I have already applied three fungicide sprays (as of mid-June); that is virtually unheard of in our area. The rains pounded us through the bloom period.”

Pistachios are pollinated by pollen carried in the wind, not by bees.

The extra moisture pushed Blackwell into pest control mode.

“There is a lot of feed out there for insects, gophers and squirrels,” Blackwell said. “We are spending a tremendous amount of time trying to control these in our orchard. We are getting ready to put on an insecticide for stink bugs,” Blackwell said. “We’ll apply some foliar nutrients at the same time.”

Despite the heavy rains, Blackwell purchased water for the pistachio crop on the open market.

“You do what you have to do to make sure you’re covered,” Blackwell said. “I am covered, but not because of the allocation through the California State Water Project. I had to buy expensive water to put on my crops.”

Bob Beede, University of California Cooperative Extension (UCCE) farm advisor, Kings County, says the overall southern San Joaquin Valley pistachio crop load varies tremendously by orchard.

“Mature orchards which bore heavily in 2009 are understandably light in 2010,” Beede said. “Young orchards unexpectedly low in crop load last year have an abundant crop this year in most cases.”

Pest control advisers and growers are reporting misshaped shells in young trees, Beede says, possibly caused by a temporary deficiency of calcium during the cool weather and its impact on the translocation of macronutrients.

Beede suggests the 2010 California pistachio crop could fall in the 350-375 million pound range. The 350-million pound threshold is considered average, but the number is a moving target due to increased pistachio plantings.

“The new average could easily become 375 million pounds once all the young trees begin to bear,” Beede said. “We anticipate young trees will make a significant contribution to the 2010 pistachio crop, even with the relatively light crop in many mature orchards due to alternate bearing.”

About 95 percent of all pistachios are the Kerman variety.

Beede suggests that growers keep a sharp eye out for late-season plant bugs. Conversations with crop consultants on pest management timing are critical. Measuring nitrogen and potassium level contents relative to the crop load is important.

Beede recommends combining fertilizer applications and irrigations to top off the trees to optimize them for kernel fill beginning late June.

Arizona pistachio grower Jim Graham is breathing easier following several late frost scares in early May. Early morning temperatures on the orchard exterior plunged to 26 F. The critical cold temperature for pistachios is 29 F on Graham’s farm located at 4,300 feet above sea level. Wind machines spared any crop loss.

Graham and wife Ruth own and operate Cochise Groves, LLC, a 160-acre pistachio ranch in Cochise located in the Sulphur Springs Valley in Cochise County.

Pistachios are an alternate-bearing crop. 2010 will be an off-year for most Western pistachio growers yet Graham’s trees are in the on-year cycle. Weather events can switch the internal production clock in trees; even on an orchard-by-orchard basis.

“I’m pretty happy with how my crop looks right now,” Graham said. “It is a good crop, but not my largest crop ever. I would be delighted to get a 4,000-pound per acre yield.”

His largest crop was 5,000-pounds-plus/acre in some orchards in 2002, the year following a hard freeze wiped out the entire crop.

Graham’s goal is to achieve a 4,000-pound crop in on-years and 2,000 pounds in the off-year. He is utilizing pruning and fertilization toward that goal.

The upbeat Graham is excited by potential grower crop prices. Worldwide pistachio stocks are down while demand is strong. “I’d like to see the price for premium split inshell No. 1 grade pistachios approach the $2/pound range,” Graham said.

U.S. pistachios are grown in California, Arizona and New Mexico. California growers produce about 98 percent of the total crop.

The Western Pistachio Association represents growers across the tri-state region. Executive Director Richard Matoian, Fresno, Calif., is hearing a mixed bag of crop projections from members ranging from a good crop to a little light.

Matoian said, “As positive as the rain was this spring, growers like rain, but not this time of the year (spring).”

The rain and cool spells could delay harvest this fall. Motoian said the crop was running seven to 10 days behind (mid-June).

“Growers would rather have an early maturing crop than a late maturing crop,” Matoian said. “A later crop has more potential for insect damage. Fall rains can reduce crop quality.”

Pistachio acreage in the three-state pistachio belt is about 210,000 acres, including about 125,000 bearing acres and about 85,000 non-bearing acres.

A big push in pistachio tree plantings from 2004-2008 included up to about 25,000 acres annually.

Plantings have slowed to the 5,000 acre/year range. Matoian believes lower plantings are tied to available water uncertainties in some areas plus some market uncertainty.

Pistachio exports five years ago totaled about 35 percent of total shipments. Exports today, Matoian says, account for about 65 percent of total shipments.

Craig Kallsen, UCCE farm advisor, Kern County, says the number of heat units this summer will ultimately determine whether the pistachio harvest will be on time or late this fall.

email: cblake@farmpress.com