Navel Orangeworm


The navel orangeworm (NOW) is the primary insect pest of almonds in California. It poses a high risk to an almond crop because the worms bore into the nut and feed on the nutmeat. Not only is the nut damaged, but the feeding opens the door to Aspergillus molds, which can produce aflatoxin contamination. Aflatoxins are considered a serious food safety issue and are regulated throughout the world.

Growers must take four critical steps in their IPM program to minimize navel orangeworm damage and risk of aflatoxin:

  • Winter sanitation to remove and destroy mummy nuts
  • Monitoring of NOW populations and timing of adult NOW moth flights
  • In-season control of NOW with insecticides or biological control agents
  • Prompt harvest before a third generation of NOW develops

In addition to navel orangeworm, almonds are subject to an array of insect and mite pests, including peach twig borer, San Jose scale and web-spinning mites. Information on these pests is included in the above resources.



In June 2019, the Almond Board of California, in collaboration with the Pistachio and Walnut Research Boards, hosted the first Navel Orangeworm (NOW) Summit. The event provided growers, processors, shippers and government agencies an opportunity to discuss the continued economic impact of Navel Orangeworm (NOW) on almond, pistachio and walnut production and marketing. Solutions to NOW pest management were discussed and on-site vendors proved additional information about their management products.

Session One - How much does NOW damage cost?

Session Two - Join the Less than 1% (Damage) Club!

Session Three - Won't you be my neighbor?

Session Four - What do we do next?