How to Manage Pests

UC Pest Management Guidelines


Saltmarsh Caterpillar

Scientific Name: Estigmene acrea

(Reviewed 4/17, updated 4/17)

In this Guideline:


Early instars of the saltmarsh caterpillar can be found in various shades of yellow-brown with long, dark hairs. Older caterpillars are densely covered with black and red hairs and often have yellow stripes running lengthwise down their bodies. Adult moths have white wings with numerous black spots on the upper surface and yellow on the undersides.


Saltmarsh caterpillar is rare, but serious pest of lettuce and other crops in Low Desert areas of Southern California. Larvae feed on leaves and cause economic losses.


To prevent saltmarsh caterpillar infestation in lettuce:

  • Monitor adjacent fields for infestations. Saltmarsh caterpillars will increase their numbers on neighboring crops such as cotton, beans or on weeds and then move into a lettuce field.
  • Place a barrier such as a 6-inch-high strip of heavy aluminum foil set on its edge in the soil, or a shallow irrigation ditch filled with water to minimize migrating saltmarsh caterpillars.


[UC Peer Reviewed]

UC IPM Pest Management Guidelines: Lettuce
UC ANR Publication 3450

Insects and Other Arthropods

E. T. Natwick, UC Cooperative Extension, Imperial County
S. V. Joseph, UC Cooperative Extension, Monterey County
S. K. Dara, UC Cooperative Extension, Santa Barbara County

Acknowledgment for contributions to Insects and Mites:
N. C. Toscano, Entomology, UC Riverside

Top of page

Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright © 2017 The Regents of the University of California. All rights reserved.

For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See our Home page, or in the U.S., contact your local Cooperative Extension office for assistance.

Agriculture and Natural Resources, University of California

Accessibility   Contact webmaster.