How to Manage Pests
UC Pest Management Guidelines
DESCRIPTION OF THE PEST
Saltmarsh caterpillar larvae are hairy and gray when first hatched, then darken to yellow, brownish, or almost black with yellow lines. They are covered with reddish or black hairs, and can be up to 2 inches long when fully grown. Eggs are spherical, whitish, somewhat flattened, about 0.03 inch in diameter, and found in clusters on the undersurface of leaves.
In the southern San Joaquin Valley, saltmarsh caterpillars are occasional pests that feed on foliage. They are primarily a problem in fall when neighboring cotton fields are defoliated.
Ditch or trench around the edges of fields that border cotton.
Organically Acceptable Methods
Cultural control and sprays of the Entrust formulation of spinosad are acceptable for use on organically grown produce.
Monitoring and Treatment Decisions
In fall, if saltmarsh caterpillars are migrating into carrots, a treatment may be necessary.
UC IPM Pest Management Guidelines:
E. T. Natwick, UC Cooperative
Extension, Imperial County