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.