Almond Update: Navel Orangeworm Challenges Took a Toll in 2023

Brian GermanAlmond Update, Almonds, News from our Sponsors

The almond industry endured a tough year for navel orangeworm challenges in 2023 for a variety of reasons. During The Almond Conference, UC Cooperative Extension Entomology and Pest Management Advisor, David Haviland explained some key factors that made 2023 an abnormal year for pest pressures. One critical aspect for effective management of navel orangeworm is a timely harvest. Haviland explained that ideally, growers can harvest nonpareils before the third flight begins and get the nuts fumigated before worms become adults. However, that was not the case in 2023 and many growers saw what happens when it is not a timely harvest.

Navel Orangeworm Challenges

“All of the worms in the nonpareils, which this year was above normal, all emerge. They all become the third flight. They lay eggs back on your nonpareils, that becomes your pinhole damage, and they lay eggs in your pollinators,” Haviland noted. “So, your pollinators are all above normal to start with, in the month of August. And then if you don’t get those pollinators off before that generation completes, let’s say in the middle of September, you now have an even greater fourth flight that’s reinvesting your pollinators.”

The situation of what Haviland described as a “nightmare scenario” originated through abnormal weather patterns. Many of the navel orangeworm challenges came from insecticide applications not lining up with the optimal timing in the pest’s lifecycle. In an average year, hull split will be synchronized in early July, right about the start of the second flight of navel orangeworm.

“We’ll spray at that timing and a couple weeks later. A beautiful system, works fairly well. Well, what did we get in 2023? We got this really long bloom that led to a hull split that was not synchronized,” said Haviland. “It wasn’t synchronized with the start of the second flight and all the timings were messed up. In fact, when the hull split came, it was kind of in the middle of the flight instead of at the start of the flight.”

Listen to the segment below.

Brian German
Ag News Director / AgNet West