Friday, May 16, 2014

Cool and Wet Can Only Help Cutworms

Doug Johnson, Extension Entomologist

 

Fig. 1. Black cutworm moth.
 
Capture of black cutworm moths in the IPM traps has been above the rolling five year average for the last several weeks. The activity of this insect has been notoriously difficult to predict over the years, even with years of data on its’ flight activity. Nevertheless given that the moth capture is above “normal” and we are experiencing unusually cool and damp weather, it may be that we should keep a closer check on our young corn plants.



Corn products that have the latest edition of “B.t.” traits, will be afforded quite a bit of protection from this pest. However, corn that does not contain “B.t.” or that contains only the1st generation “corn borer B.t.” traits will be at greater risk, if an economically important population occurs. Our traps are unlikely to provide a definitive warning, so scouting for the damaging caterpillars is the best way to insure that major loss will not occur.
 
Fig. 2. Black cutworm larva
Cutworm larvae are light grey to nearly black and may have a faint, narrow mid-dorsal stripe. Larvae vary from ¼” long after hatch to 1-3/4” when full grown. Larger larvae tend to curve themselves into a “C” shape around the plant and wiggle vigorously when handled. Damage symptoms are cut or wilted plants.

Scouting should begin from a randomly selected starting point. Examine 20 consecutive plants per location and record the number of cut plants. This should be done at multiple locations (at least five) in the field. Determine the percent cut plants by dividing the total number of plants cut by the total number of plants inspected and multiply by 100.
If an average of 3% cut plants and 2 or more live cutworm 1” or smaller per 100 plants examined are found, a control should be considered. Remember if you cannot find live larvae, the population may have already completed a generation and control is not warranted

3 comments:

  1. http://www.burbagssale2014.com/ Burberry Outlet
    http://www.airmaxshoesfactory.com/ Air Max Shoes
    http://www.coachblackfriday2014.com/ Coach Black Friday
    http://www.coach-storeoutletonline.com/ Coach Black Friday
    http://www.coachcoachoutlet.com/ Coach Cyber Monday
    http://www.coachxfactory.com/ Coach Factory
    http://www.coach-factoryoutletonline.net/ Coach Outlet Factory
    http://www.coach-outletonlineusa.com/ Coach Outlet USA
    http://www.coach-pursesfactory.com/ Coach Purses Factory
    http://www.coachpurseusa.com/ Coach Purses USA
    http://www.coach-storeoutlet.com/ Coach Store Outlet
    http://www.coach-pursesonline.com/ Coach Purses On Sale
    http://www.monsterbeatsbydres.com/ Monster Beats Outlet
    http://www.louis-vuittonblackfriday.com/ Louis Vuitton Outlet
    http://www.lv-guccishoesfactory.com/ Louis Vuitton Factory
    http://www.marcjacobsonsale.com/ Marc Jacobs On Sale
    http://www.mcmworldwides.com/ MCM Outlet
    http://www.mcmoutlet-jp.com/ MCM 店铺
    http://www.oakleysunglassesfactory.com/ cheap oakley sunglasses
    http://www.michaelkorsmas.com/ Michael Kors Outlet
    http://www.michaelkors.so/ Michael Kors Outlet
    http://www.michaelkorsfactory-store.com/ Michael Kors Factory
    http://www.michaelkorsoutletr.com/ Michael Kors Outlet
    http://www.michael-korsfactoryonline.com/ Michael Kors Factory Online
    http://www.newcoachfactoryoutlet.com/ Coach Factory Outlet
    http://www.north-faceoutletonlines.net/ North Face Outlet Online
    http://www.polo-outletstore.com/ Polo Outlet Store
    http://www.ralph-laurenhome.com/ Ralph Lauren UK
    http://www.saclongchamppairs.com/ Sac Longchamp Pairs
    http://www.tcoachoutletonline.com/ Coach Outlet Online
    http://www.the-coachfactoryoutlet.com/ Coach Factory Oultet
    http://www.barbour-jacketsoutlet.com/ Barbour Jackets Outlet Online
    http://www.canada-gooser.com/ Canada Goose Outlet
    http://www.guccishoesuk-2014.com/ Gucci Outlet Online
    http://www.michaelkorsstates.com/ Michael Kors Outlet
    http://www.moncler-clearance.com/ Moncler Clearance
    http://www.moncler-jacketsoutletonline.com/ Moncler Jackets Outlet Online
    http://www.northsclearance.com/ North Clearace Outlet
    http://www.polo-ralphlaurenonline.com/ Polo Ralph Lauren Outlet Online
    http://www.woolrich-clearance.com/ Woolrich Clearance
    http://www.cvshopfactory.com/ shop.coachfactory.com
    http://www.mksfactoryoutlet.com/ Michael Kors Factory Outlet
    http://www.zxcoachoutlet.com/ Coach Outlet Online USA
    http://www.thebeatsbydre.net/ Beats by Dre
    http://www.superbagsmarket.com/
    http://www.newoutletonlinemall.com/ Coach Purses Outlet Online
    http://www.clickmichaelkors.com/ Michael Kors USA

    ReplyDelete