Gypsy Moth in Toronto, 2007 by 9WvuL0lX

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									Gypsy Moth in Toronto, 2007
World distribution of gypsy moth
Gypsy Moth Distribution in Canada:
  CFIA Quarantine Zones 2005

     Gypsy Moth in Canada
Gypsy Moth in Ontario: 1981-2006
             (Moderate-to-Severe defoliation)

             400,000
             350,000
             300,000
  Hectares




             250,000
             200,000
             150,000
             100,000
              50,000
                  0
                 81

                 83

                 85

                 87

                 89

                 91

                 93

                 95

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                 99

                 01

                 03

                 05
               19

               19

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               20

               20
                               Year
Adults (July/Aug.)

            The female is creamy
             white and does not fly
             but emits a pheromone
             to attract the males. A
             single male can mate
             with many females
Egg masses (July – April)

                Egg masses contain
                 between 50 and 1000
                 eggs. The egg masses
                 are covered with hairs
                 from the female’s
                 abdomen and can
                 survive temperatures as
                 low as -30oC.
          New and Old Egg Masses
   New:
     Firm to touch

     Eggs pop when
      squeezed
     Dark beige colour

   Old
     May be soft to touch

     Exit holes present

     Ragged bleached
      appearance
Small Larvae (May)
            This stage lasts 7-10
             days after eggs hatch in
             May. They linger
             around the egg mass for
             several days if weather
             is cool or rainy, then
             climb trees where they
             can drop on silken
             threads and disperse in
             the wind.
          Mature larva (May/June)
   Large larvae feed at night for 4 to 6 weeks and
    generally rest during the day or wander when
    populations are high.
              GM Larval feeding
   During the caterpillar stage, each gypsy moth eats
    about one square meter of foliage
Pupa (June/July)

           Larvae are changing to
            moths, generally late
            July to early August.
            After about 10 days the
            adults emerge from the
            pupal case.
Natural Control
           Favoured host trees
   All oaks
   All aspen and poplar
   White birch
   All willow
   White pine
   Beech
   Basswood
   All apple
         Impacts: Environment
   Reduced tree vigor;
   Tree crown dieback and mortality;
   Damage to other trees (bark);
   +ve and –ve impacts on wildlife;
   Reduced shade, dry soils;
   Increased stream temperatures and reduced
    water quality;
   Increased water fluctuations.
        Impacts: Human Health
   Allergic reactions to hairs, wing scales;
   Rashes and skin irritations;
   Respiratory tract irritations;
   Eye irritations;
   Psychological reactions;
   Slippery sidewalks and roadways;
   Hazard trees – dead branches and trees.
           Impacts: Economic
   Costs to homeowners:
       Pesticide treatments;
       Cleanup of insect body parts;
       Egg mass removal;
       Pruning dead branches;
       Dead tree removal and replacement
       Liability for damage to property and personal
        injury.
              Impacts: Economic
   Costs to the Municipality:
       Tree removal and replacement;
       Reduced use of damaged parklands and
        recreational facilities;
       Increased tree inspections;
       Tree pruning and maintenance;
       Liability for damage to property and personal
        injury;
       Tourism: First impressions.
       Good decisions are based on good
                information!
   Delineate the outbreak
   Assess egg mass densities
   Assess egg mass size
   Assess egg mass
    distribution
   New/old egg mass ratio
   Pathogen status
   Management options
   Management constraints
   Available resources
                 Action Thresholds
                100
                90
                80
Defoliation %   70
                60
                50
                40
                30
                20
                10
                 0
                      25     125   250   1250   2500   5000   12000   18500   25000

                                         Egg masses per ha



                          Nuisance abatement
                          Foliage protection
                          Prevention of tree mortality
                          Urban vs. natural forest
      Management Options: IPM
   Do nothing
   Maintain or enhance
    tree health (PHC)
   Destroy Egg masses
   Barrier bands
   Burlap skirts
   Homeowner sprays
   Property maintenance
   Ground/Aerial spraying
    The Insecticide: Foray 48B
BioForest recommends the biological insecticide
  Bacillus thuringiensis var. kurstaki (Btk):
   Naturally occurring bacteria

   Harmless to fish, birds, mammals and most

    non-target insects
   Approved by PMRA, EPA, WHO, OPAC

   Biodegradable

   Must be ingested – delayed mortality
              What's in Bt?
Mostly water (about 75%)
About 3% Bt
Inerts are added to maintain product quality
 and microbial purity:
   All are food grade materials (EPA List 4)

   E.g. Alfalfa, acetic acid, beer, bread crumbs,
    decanol, glycerin, lactose…
Rachel Carson described Btk in
Silent Spring as an “… important
answer to the problems of such
forest insects as the budworms
and the gypsy moth.”
     Has Bt been sprayed over inhabited
               areas before?
   Gypsy moth programs in USA and Canada
   Victoria B.C. 1999
       Ministry of Environment 1999
   Auckland N.Z. 1998 (up to 32 appl.)
       Ministry of Ag and Forestry 2001
   Waskesiu, Prince Albert National Park, 2003-2005
   Village of Candle Lake, Saskatchewan – 2003 + 2004
   U.S. gypsy moth programs
   Mississauga, 2006
Factors influencing spray
     effectiveness:

 Pest population density
 Insecticide, dose and applications

 Aircraft and navigation

 Weather (oC, RH, wind)

 Block size

 Insect and host development
What can you expect for results?
   Greener trees
   Fewer caterpillars

   Fewer egg masses

   Some gypsy moth will survive

   Some defoliation will occur

   Some trees will die.
Treated vs. Untreated
       Potential Constraints
   Technical: Aircraft availability
   Financial: Cost share arrangement
   Operational: Pearson & major highways
   Time: Delays in acquiring permits
   Legal: Transport Canada exemption
    and actions initiated by opponents
   Political:?

								
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