Monitor for omnivorous leafroller, western grapeleaf skeletonizer, grape
leaffolder, and orange tortrix (in coastal areas) 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
| Omnivorous leafroller
and orange tortrix |
Bloom damage |
Veraison 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.
|
Identification tip: Rotting and raisining (drying up) of Thompson
seedless grapes following chewing damage by omnivorous leafroller larvae. |
Orange tortrix
The larva is straw-colored
with a brown head and prothoracic shield.
|
Identification tip: Berries and stems damaged by orange tortrix
have dry-calloused surfaces. |
| Grape leaffolder |
Bloom damage |
Veraison damage |
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.
|
No photo available. |
| Western grapeleaf skeletonizer |
Bloom damage |
Veraison damage |
Western grapeleaf skeletonizer
Identification tip: Feeding by larvae of western grapeleaf
skeletonizer leaves the surface of foliage pale and scraped. 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.
|
Continued feeding by western grapeleaf skeletonizer leaves the surface
of foliage pale and scraped. |
