HOT Downloads:

WBC
* Map of WBC trap catch by county (pdf), from July 24, 2010
* WBC damage to dry beans (pdf), with pictures of WBC leaf, pod, and bean feeding.
* Managing WBC in dry beans (pdf) with recommendations for 2010.

OTHER
* Bulletin on Soybean Defoliators (pdf).
* Scouting for spider mite (pdf)

**Spray Recommendation for Central Michigan Dry Beans**
Gratiot, Isabella, Kent, Mecosta, Montcalm, and Midland Counties
Issued July 28, 2010

I am making a spray recommendation for Western Bean Cutworm in dry bean fields in the following Michigan Counties: Gratiot, Isabella, Kent, Mecosta, Montcalm, and Midland.

I urge growers to treat fields WITH PODS as soon as practical, ideally within the next 7 days. This spray will control WBC caterpillars before they chew into pods. While I am not recommending a specific product, many pyrethroids have good efficacy against WBC, plus provide residual activity to control larvae hatching a week or more after application. The treatment will also control cloverworm, Japanese beetle, and potato leafhopper, all of which are increasing. For fields that are only flowering, delay treatment until PODS are present.

This recommendation is based on several factors. Corn is now mostly unattractive for egg laying, moth numbers remain high in traps near dry bean fields in central Michigan, and I believe that moth catch peaked last week in the state. There is no need to panic - experience from 2009 showed that in podded fields treated within 1-2 weeks after peak flight, bean damage was low or none.

As a good entomologist, I urge growers to check fields for pod feeding before spraying to confirm the presence of WBC. But the difficulty of scouting dry beans, the potential time needed to arrange for a spray, and the threat to bean quality at harvest dictate that this more general recommendation be made to deal with the reality of the situation.

WBC Trapping as of July 24

As of July 24th, there were 40,288 moths caught in Michigan milk jug traps, compared to 2,192 by the same time last year. The map below shows total trap catch by week. It only includes sites that reported catch each week since June. Unfortunately, many of our trap locations are not reporting data weekly, which is necessary to detect local peaks. But the map clearly shows that overall flight has not peaked yet and there could be 3-4 weeks more of egg laying into early August.




Below is more detailed information on overall WBC trap catch. In each county, I list the total number of moths caught, the average by trap (some counties have few traps while others like Montcalm have many), and the highest total reported at an individual site. As usual, we have a hot spot along the west coast or Michigan and in the central corn/dry bean area of Montcalm, Gratiot, and Isabella. There also appears to be hot spots along the border of Indiana, but there are fewer people trapping in these counties, which may inflate catch. To download and print a copy of the map, click here [WBC map July 24]



For other networks, click on the state or province name below.
Ontario - operated by Tracey Baute with the Ontario Ministry of Ag, Food, & Rural Affairs
Ohio     - operated by Andy Michel and Ron Hammond at OSU

Thank you to the following groups for funding WBC trapping in Michigan
 

Western bean cutworm information for 2010

In 2009, western bean cutworms moved through Ontario and Ohio into Western Pennsylvania and Quebec. Damage to corn and dry beans was reported in west and mid-Michigan. Below is a list of 1-2 page bulletins and reports generated after the field season. These provide information on results from studies, as well as recommendations for the 2010 season.

General
* Western bean cutworm trap catch maps (pdf) for Michigan and the region from previous seasons

Corn
* Managing WBC in field corn (pdf), recommendations for 2010.
* WBC biology trial (pdf) following caterpillars on infested corn plants.
* Picture guide (pdf) showing WBC caterpillars by size and location on corn
* Pictures of WBC in whorl stage corn (pdf)
* Herculex efficacy trial (pdf) for rootworm and WBC.

Dry beans
* WBC damage to dry beans (pdf), pictures of WBC leaf, pod, and bean feeding.
* Managing WBC in dry beans (pdf) with recommendations for 2010.
* Egg mass trial (pdf) infesting dry bean plots with different egg mass densities
* Larval trial (pdf) infesting dry bean plots with different caterpillar densities
* Insecticide trial (pdf) comparing a Warrior spray to Cruiser, Thimet, and Temik

For a complete list of free extension bulletins
covering WBC as well as other crops and insects,
click the 'extension' tab on the right side of this page.

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