In this issue:

Corn Earworm Migration Continues

CEW - Frequently Asked Questions

How to Monitor for CEW

Cabbage Looper Still Active

Pesticide Residues and IPM

Email Access and Pest Info

Cabbage Looper Still Active

Cabbage looper and imported cabbageworm (white butterflies active during the day) are still very active. Any cabbage, broccoli or cauliflower will still be attractive for egg-lay; this can continue throughout much of September. Like corn earworm, cabbage looper initially migrates into the state and cannot overwinter in MN. Looper moths have been coming in since early July. Cabbageworm does overwinter in MN, and typically goes through 2-4 generations/yr. Both pests have been active this year in our research plots at Rosemount (Dakota Co.). Action thresholds for both pests are based on minimizing contaminant damage to the heads (or final marketable produce). Thresholds are approx. 30% of the plants infested with one or more larvae of either species during vegetative growth stages. Once plants are producing heads, the threshold reduces to 10%. Results from our research with a variety of new 'biologically-based' insecticides will be summarize in future newsletter issues.

For more information on IPM for cole crops, including the biology, color photographs, etc.,see the VegEdge Fact Sheets at: http://www.vegedge.umn.edu/intro/pestfact.htm

Co-Editors: Bill Hutchison, Department of Entomology, University of Minnesota
Jeanne Ciborowski, IPM Program, Minnesota Department of Agriculture
Production Editor: Rebecca Hines, Research Associate, University of Minnesota

Disclaimer
Reference to products in this publication is not intended to be an endorsement to the exclusion of others which may have similar uses. Any person using products listed in this publication assumes full responsibility for their use in accordance with current directions of the manufacturer

Last Revised November 11, 1999.
The University, including the Minnesota Extension Service, is an equal opportunity educator and employer.©1999 Minnesota Extension Service, University of Minnesota. All rights reserved. Contact copyright@extension.umn.edu for information on reproduction or use of this material.