Yellownecked Caterpillars

Denise Attaway  |  4/29/2011 12:20:18 AM

When disturbed, yellownecked caterpillars often elevate the anterior and posterior ends of their body, clinging to the substrate by only a few middle pairs of pro-legs. Photo by Jerry A. Payne, USDA/ARS,

Go to Blueberry Insect Pest Guide

Go to Blueberry Insect Pests Home Page

Click on the links above to go to the Blueberry Insect Pest Guide home page or the Blueberry Insect Pests home page.

During the larval stage, yellownecked caterpillars are colorful caterpillars that are moderately clothed with long, white hairs. Their heads are usually black, the neck is narrowly ringed with yellow or orange, and their bodies are conspicuously marked with longitudinal yellow lines against a black background. Fully grown larvae reach a length of about 2 inches. When disturbed, these insects often elevate the anterior and posterior ends of their body, clinging to the substrate by only a few middle pairs of pro-legs. Adults of these caterpillars are light brown moths with a wingspan of 1.5 inches to 2 inches. The forewings are usually banded with dark brown lines, and the hind wings are somewhat lighter in color than the forewings. Adults are seldom seen because they are active at night.


  • All of these species pass the winter as pupae in the soil.
  • Adults emerge in early summer and lay their eggs in groups of 50 to 100 on the undersides of leaves.
  • After hatching, young larvae often feed together on a single leaf for several days and then gradually disperse to nearby foliage where they continue to feed in loose aggregations.
  • Larvae complete development, drop to the ground and pupate under their host plants.
  • There is only one generation per year.

  • Young larvae skeletonize blueberry foliage.
  • Older larvae are able to consume entire leaves and may completely defoliate small plants.
  • Extensive feeding may retard growth, but plants are seldom killed because the injury occurs late in the growing season.

  • Blueberry bushes should be inspected every two weeks.
  • Clusters of older larvae are usually quite visible feeding on the terminal leaves.

  • Manually remove the caterpillars.
  • Destroy the colonies with insecticide from a small, portable sprayer.

Yellownecked Caterpillars in Blueberry. North Carolina State University Cooperative Extension Service. July 2003. Retrieved 13 July 2010.

Rate This Article:

Have a question or comment about the information on this page?

Innovate . Educate . Improve Lives

The LSU AgCenter and the LSU College of Agriculture