Dry Edible Beans: Mexican Bean Beetle (Epilachna varivestis)

Excerpt from Field Crop Protection Guide (Chapter 5)

Table of Contents

1. Description
2. Integrated Pest Management Options
   • dimethoate – Cygon 4 E, Lagon 480 EC
   • endosulfan – Thiodan 4 EC, Thionex EC, Thionex 50 WP
3. Related links...

Description

This is the only member of the lady beetle family in Ontario that eats plants. All the other lady beetles are beneficial predacious insects. The adult beetles are oval in shape, approximately 6 mm (1/4 in.) in length with 16 small black spots on their coppery-red backs, resembling a lady beetle. The heads of the Mexican bean beetle, however, are the same coppery-red colour as their backs, whereas lady beetlesí heads are typically black and white. Adults will darken with age to an orange-brown colour. The larvae are yellow and have six rows of long, branching, black-tipped spines along their backs.

Image 1. Mexican bean beetle adult and larva. The beetles have 16 small black spots on their coppery-red back. Larva have black-tipped spines along back.

Integrated Pest Management Options

Less of a problem in very hot, dry summers. Early-maturing bean varieties and fall plantings may be grown with little or no injury. Several natural enemies help keep populations below action thresholds. Insecticides are only recommended if populations are extremely high, as they will also kill the natural enemy population.

Comments
Do not feed treated threshings or crop refuse to livestock. 7 days to harvest.

Comments
Do not feed treated threshings or crop refuse to livestock. 2 days to harvest. Do not use on lima beans.

Related links...