In this Issue:
SPECIAL FEATURE
Corn Earworm Trap Catch and Sweet Corn Ear Infestations in Minnesota: Research Update
VEGETABLE NEWS
Vegetable Insect Pest Update
STRAWBERRY NEWS
The 2006 Strawberry Season: Short, Sweet and Buggy
APPLE NEWS
| Vol 3 No. 7 | June 30, 2006 |
Vegetable Insect Pest Update
Eric Burkness, Department of Entomology, University of Minnesota, St. Paul
As we approach harvest for early planted cabbage, pest pressure remains low with very light infestations of diamondback moth (DBM) and cabbage looper (CL). Scouting should intensify next week as we typically see the primary populations of CL moths migrate into Minnesota the 1st week of July.
Potato leafhopper (PLH) populations have continued to increase in the Rosemount area this week. PLH counts in alfalfa have increased from 0.4/sweep early last week to 1.3/sweep at the end of last week and were 0.8/sweep this week. This fluctuation in population is not unusual as the population can change rapidly based on weather systems moving through the area. We have also observed an increase in PLH in late planted snap bean (unifoliate stage), which can also explain some of the population change in alfalfa. The unifoliate snap beans have populations of PLH ranging from 3-5 / foot of row, which is above the treatment threshold of 2/foot. Again, for PLH, it is important to scout fields frequently because of the potential for populations to quickly increase or decrease based on weather conditions.
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Corn earworm (CEW) and European corn borer (ECB) continue to be trapped at low levels across the state. As early planted sweet corn begins to silk fields should be monitored using pheromone or black light traps. Treatment decisions should be made either before or just as silk is emerging from the ear. Once the larvae enter the ear, there are no effective treatment options available. For information on the relationship between trap catch and ear infestation for CEW see companion article this week regarding the relationship between corn earworm trap catch and sweet corn ear infestations in Minnesota. |
 Black light trap (left), Scentry trap (middle), and Hartstack trap (right). |
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Striped cucumber beetle (SCB) populations appear to have leveled off in the Rosemount area this week. This should be an indication that the beetles have stopped migrating into fields. The next generation of SCB should start emerging from the soil in July. One reminder as the cucurbit crops begin to vine and flower, is to scout fields and make final management decisions for squash bug or SCB before vine growth closes the rows.
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 Jean Ciborowski, 651-201-6217, jeanne.ciborowski@state.mn.us, MDA, 625 Robert St. North, St. Paul, MN 55155-2538. 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: http://www.mda.state.mn.us/ipm/ipmnews/
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.
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