Monitor for omnivorous leafroller, western grapeleaf skeletonizer, grape
leaffolder, orange tortrix (in coastal areas) and light brown apple moth
from bloom through veraison. Continue monitoring for western grapeleaf
skeletonizer and grape leaffolder until harvest.
Use the photos below to identify caterpillars
and their damage. Also look for natural
enemies of caterpillars. Names link to more information on identification
and management.
Click on photos to enlarge
Caterpillar |
Damage |

Omnivorous leafroller
Identification
tip: Larvae have a black or brown head capsule. Mature larvae are
cream to brownish green with whitish slightly convex tubercles on
the top of the abdomen. |

Identification tip: Omivorous leafroller and orange tortrix
both make silken nests on grape flowers. |

Orange tortrix
The larva is straw-colored
with a brown head and prothoracic shield. |

Grape leaffolder
Identification tip:
Mature larvae are translucent-greenish with small black spots located
above the second pair of legs, distinguishes later larvae from omnivorous
leafroller. |

Identification tip: Grape leaffolder larvae curl leaves and tie them
together with silk.
|
Light brown apple moth |
Damage |

Light brown apple moth
Identification tip: The mature larva is pale-to-medium green
with a light yellow-tan head.
The first segment behind the head is greenish brown with no dark
markings. However, larvae
cannot be reliably identified using morphological characters. Take
suspect larvae (preferably
alive) to the County Agricultural Commissioner’s Office for
proper identification. |
No photo available. |
Western grapeleaf skeletonizer |
Damage |

Western grapeleaf skeletonizer
Identification tip: Feeding by larvae of western grapeleaf
skeletonizer leaves the surface of foliage pale and scraped.
|

Identification tip: Whitish spots on a grape leaf caused by feeding
of first-instar
larvae. |

The fourth- and fifth-instars are yellow with two purple and several blackish
bands. |

Typical damage by first-generation western grapeleaf skeletonizer on lower shaded
leaves of grapevine. |