Like a pair of trusty wagon-pulling mules, “Kerman” and “Peters” have successfully carted the California pistachio industry from a novelty crop to a major specialty crop with huge growth potential.
Since the late 1980s when the U.S. embargoed Iranian pistachios in the wake of the Iranian hostage crisis, California pistachio production has exploded.
The female variety, Kerman, introduced in 1957, and its pollinator male variety, Peters, command virtually 100 percent of California’s 200,000 acres of bearing and non-bearing pistachios that have produced more then 400 million pounds of pistachios en route to perhaps double that within the next five years.
Kerman is a time-tested reliable yielder; however, it has its limitations, explains University of California Kern County Farm Advisor Craig Kallsen who detailed those limitations at the statewide pistachio field day in Visalia and in an excellent article in California Agriculture, the research publication for the University of California division of agriculture and natural resources.
Kallsen detailed variety trials of several very promising new varieties that have recently been released offering advantages over Kerman. For example, one or all:
• Bloom earlier
• Harvest earlier
• Are less alternate bearing
• Have greater split nut percentages
• Have larger nut size
• Show less insect damage
• Have less closed shell percentages.
Golden Hills, Lost Hills, Kalehghouchi and Aria are the varieties Kallsen and his colleagues have been testing.
Golden Hills and Lost Hills came out of a University of California pistachio breeding program supported by the now defunct California Pistachio Commission. It was conducted by Joe Maranto, UC farm advisor, and Dan Parfitt, UC ag Extension service pomologist. These were released to nurserymen five years ago and there are about 800 acres of the two planted in the state. Last year was the first for commercial production. Pistachio trees do not begin to yield until fifth or sixth leaf.
The Kalehghouchi and Aria varieties originated in Iran.
In UC trials in several areas of the state, Kallsen reports the flowering periods for females Golden Hills, Lost Hills and Kalehghouchi overlap well with the male pollinator Randy. Aria occasionally bloomed earlier than Randy. All bloomed earlier than Kerman.
This early bloom translates into an earlier harvest. One of the drawbacks with a single variety, Kerman, dominating the acreage is that harvest is very compact. It now begins in early September and ends by the second week of October. This two to three week harvest window taxes harvesting and processing, particularly in an on year when the crop is large. Stretching that harvest time frame would lessen the stress on the industry infrastructure.
On average, Lost Hills, Golden Hills and Aria are two weeks or earlier to harvest than Kerman. Kalehghouchi was three days earlier.
Alternate bearing is a major issue with Kerman. The new varieties offer hope from the UC trials that that will be mitigated. However, Kerman does not exhibit alternate bearing characteristics until about the 10th leaf.
These new varieties will continue to be evaluated in research trials and now in commercial production.