In this Issue:
GUEST ARTICLES
Why Use High Tunnels in minnesota?
USDA-Farm Service Agency County Committee Election
VEGETABLE NEWS
Vegetable Insect Update
STRAWBERRY NEWS
Using Computer Models to Time Fungicide Sprays in Strawberries
APPLE NEWS
Weekly Trap Counts: June 27 - July 7, 2005
REMINDER: Apple Maggot Emergence Has Begun
| Vol 2 No.9 | July 11, 2005 |
Vegetable Insect Update
Suzanne Wold-Burkness, Eric Burkness, and Bill Hutchison, Dept. of Entomology, Univ. of Minn.
Potato Leafhopper (PLH): In late-planted snap beans, PLH nymphs are increasing (0.8/leaflet). In snap beans treated with a foliar spray, the number of PLH nymphs is considerably lower (0.1/leaflet). The threshold for PLH nymphs at this stage (blossom-pin bean) is 1/leaftlet. |
Cabbage Looper (CL): The first CL moth was caught on June 30th in our pheromone traps. CL egg lay is continuing, with 10% of the plants infested with CL eggs on July 5th. As stated in the June 20 th issue, treatment decisions should be based on 10% of the plants infested with CL larvae. Therefore, given the number of eggs found, we will continue sampling to assess the need for a treatment.
Corn Earworm (CEW): CEW moth counts are increasing in certain areas of the state. At Rosemount (Dakota Co.), CEW moth counts were at 7/trap on June 28th and 2/trap on July 5th, and Blue Earth (Faribault Co.) reported 12/trap on June 30th, and 4/trap on July 4th. As Bill Hutchison stated in last week’s “web only” CEW Alert article (http://www.vegedge.umn.edu/MNFruit&VegNews/Vol2/630CEWAlert.htm), sweet corn that is silking should be monitored for CEW eggs. For updated CEW information, visit the CEW trapping page at http://www.vegedge.umn.edu/2005/CEW.htm.
For more information on treatment thresholds and labeled insecticides, see the 2003 article at: (also check current insecticide labels prior to use) http://www.vegedge.umn.edu/mnvegnew/vol5/vol5n4.htm
European Corn Borer (ECB): The first generation flight of ECB should be nearing the end, and counts of ECB moths remain low across the state. We do not expect the 2 nd flight of ECB to begin until 1400 DD (we are currently at 1183 DD). In contrast, ECB moth counts in St. James (Watonwan Co.) are much higher (>150/night), suggesting that moths caught at this location are the univoltine strain of ECB. Based on recent years at Rosemount, if the univoltine flight continues at >20 moths/night, for several nights, there is a good possibility of egg-lay on tasseling or silking corn (i.e., >4% of plants with egg masses). These infestations can result in significant ear infestations. We will continue to monitor these flights. For updated ECB information, visit the ECB Moth Catch page at http://www.vegedge.umn.edu/2005/MNlist.htm.
ACKNOWLEDGEMENTS
Co-Editors: Bill Hutchison (hutch002@umn.edu), Department of Entomology, University of Minnesota, Jeanne Ciborowski, Minnesota Department of Agriculture, Ag. Resources Management and Development Division, and Suzanne Wold-Burkness (woldx018@umn.edu), Department of Entomology, University of Minnesota
The Newsletter is published weekly from May through August, cooperatively, by the Minnesota Department of Agriculture (MDA) and the University of Minnesota (U of MN). Reports are posted on the U of MN and MDA web sites on Fridays. If you have suggestions and/or comments, please send your contributions by 4 p.m., Wednesday to Jeanne Ciborowski, 651-297-3217, jeanne.ciborowski@state.mn.us , MDA, 90 W. Plato Blvd., St. Paul, MN 55107-2094. You can access the Newsletter at the U of MN web site in htm format at: www.vegedge.umn.edu/MNFruit&VegNews/mnindex.htm and at the MDA web site in pdf format at: www.mda.state.mn.us/biocon/fruitreports/
Partial funding for this publication is provided through partnership agreements with the Minnesota Fruit and Vegetable Growers Association (MFVGA) and the United States Department of Agriculture – Risk Management Agency (RMA). These institutions are equal opportunity providers.
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 manufacturer directions.
The University, including the Minnesota Extension Service, is an equal opportunity educator and employer. ©1999-2005 Minnesota Extension Service, University of Minnesota. All rights reserved. Contact copyright@extension.umn.edu for information on reproduction or use of this material.