Navel orangeworm damage in almonds

Navel orangeworm (NOW) flights have arrived as expected across tree nut territory. And while producers may already have completed their “mummy spray,” more treatments could be needed this summer, depending on degree days and what’s found in field traps.

NOW is the primary pest found in CA almonds and pistachios, but is seen more and more in walnuts. NOW is a pervasive pest that can do great damage to the nuts. That’s why entomologists recommend producers monitor traps in their fields and evaluate egg and moth counts to identify potential next flights. Three to 4 adult flight periods can occur per season, and sprays should be timed according to degree-days and again at harvest, as needed.

An effective management plan for NOW can also help with peach twig borer (PTB) control. PTB is mainly a concern in Northern CA during the early part of the season in smaller orchards. PTB settles into fresh shoots in young trees but can delve into nuts in older orchards at harvest. PTB may not be recognized, however, if NOW are feeding.

Hull split is a crucial time to get a handle on both insects. The good news is that with the right treatment program, producers can cover multiple pest life stages throughout the season.

We recommend Minecto Pro® and Besiege® insecticides to do just that. Minecto Pro is a broad-spectrum insecticide that helps reduce damage that contributes to mummy nuts which become a food source for NOW in May and June. Its 2 active ingredients, cyantraniliprole and abamectin, protect against multiple overlapping pest populations, including mites. Minecto Pro is effective on NOW larvae.

But NOW is not managed with a single treatment; NOW requires multiple treatments. For a second treatment, Besiege provides egg-to-adult-moth control and is ideal for use at hull split. Besiege delivers outstanding knockdown and also provides long-lasting residual control for PTB, codling moth, leaffooted plant bug and walnut husk fly.

Additionally, Besiege is a wise choice for managing resistance because it contains 2 active ingredients. As a Group 28, 3 insecticide, the chlorantraniliprole and lambda-cyhalothrin combo provides a safety net for resistance management when more than 1 generation of pests is present.

NOW is the time to protect your crop. Watch for pest flights in orchards and be prepared with a solid treatment plan.

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