He said research showed that dropping the speed from 2.5 miles per hour to 1.8 miles per hour brought a significant improvement in NOW control and a value increase for yields.

Doll said this year’s crop is about two weeks ahead of schedule this year, which could mean an earlier hull split and kernel fill. That has ramifications for water management as the season moves on.

“You may be able to get into and out of the orchards earlier and be hunting in October,” Doll said.



A hot spell the first couple weeks of March could result in smaller nut sizes, he said.

He said tattered leaves on a Padre could be an indicator of shot hole damage. Some Padre nuts are showing “early suture development,” he said. “I don’t know if they will split early, but you need to keep an eye on it,” he said. “You could get some egg laying in that area.”

A willowy branch appearance may be an indicator of a boron or potassium deficiency, Doll said. He recommends a hull analysis and warned against applying boron “if you are importing well water” until you know test results.

Sampling for potassium is best done in mid-July, Doll said.


Want the latest agricultural news each day? Click here for the Western Farm Press Daily e-mail newsletter.


There’s little doubt that the drought could cut yields. But there are ways to stretch water use to maximize yield, said Gurreet Brar, UC Fresno County farm advisor.

And owners of the orchard where the field day was held say they have no choice. Though the orchard is loaded with nuts at this stage, owners Eric and Gina Rushing know they face a challenge.

As to the need to stretch water, Gina Rushing says, “we have to; we have no choice.”

Brar said regulated deficit irrigation, pioneered in Australia, can work; that it can even improve fruit quality and yield. Still better, he said, rather than cutting irrigation at certain stages, is cutting by a given percentage with each application of water and maintaining uniformity and tuning up irrigation efficiencies while taking into account formulas for evapotranspiration.

Brar warned that cutting back on post-harvest irrigation affects yields in the following year. Across the San Joaquin Valley, there are concerns about lingering drought effects that could cut yields in 2015.

If water to trees is cut at each watering, Brar said, “trees adjust to available water. They are living things that adjust.”

He recommends using pressure bombs to measure water stress.