This year’s walnut harvest in Glenn County got under way the third week of September, when growers began shaking Ashleys. Next up were Vinas and Serrs, followed by Tulare and Howards.
Growers are expected to wind up the season toward the end of October when they will pick up the last of the Hartleys and Chandlers.
Despite blooming about two to three weeks later than usual, due to cool temperatures in the spring, the mid-season varieties took advantage of some hot summer weather and appear to be making up some of the lost ground.
As a result, nuts reached maturity only about a week behind normal, says Bill Krueger, University of California Cooperative Extension Farm Advisor for the county.
Growers want to prevent a repeat of last year’s late harvest, when many of them got caught with nuts still on the trees when fall rains began. Consequently, he notes, a number of them have been spraying trees with ethephon to shorten the harvest period.
Applied when walnuts reach maturity, or shortly thereafter, the plant growth regulator accelerates hull cracking and separation from the shell. This advances walnut harvest by four to seven days, depending on the season and variety. Also, it can increase nut value by promoting lighter kernel color and, possibly, by reducing insect damage, Krueger says.
“Last year, quite a few growers in the county used ethephon. I think even more will be using it this year.” He advises growers to check with their hullers before treating with ethephon to insure an orderly harvest and to avoid a backup at the dehydrator.
Information on proper application and timing of ethephon is available at http://cekings.ucdavis.edu/newsletters/Nut_Crops/?newsitem=39678
Some growers were concerned by a midsummer nut drop in Howard orchards. The phenomenon, which has happened before, could be related to hot weather, following an unusually cool spring and early summer, Krueger says.
“Whatever the reason, the trees still finished the growing season bearing a good number of nuts,” says.
In fact, just prior to the start of harvesting, walnut production prospects for the county overall looked promising.
“Based on what I’ve heard and seen, it should be a really good crop,” Krueger says. “There were some limb breakage problems earlier due to the nut load, and I’ve seen numerous doubles and triples.”
While it’s too soon to assess the quality of this year’s walnuts, he’s encouraged by what hasn’t appeared on the trees.
“For the second year in a row, we had more rain than normal in the spring, and growers were watching for possible blight problems,” he says. “But, I haven’t seen a lot of blight. At this point, it looks like a pretty good quality year.
“Prices are good, and a lot of people are pretty excited about walnuts. There’s been a real boom in new walnut acres for the past few years, and it doesn’t look like it will be slowing down any time soon.”