First Detectors

European Gypsy Moth(Lymantria dispar)

First Detectors

Why be Concerned about Gypsy Moth?

Tree defoliator

Attacks more than 300 species of woody plants

Increases host susceptibility to secondary pests and diseases

Greatest damage occurs at first introduction Appears as an outbreak pest in its native range

and established areas Over 1 million acres defoliated in the U.S. in

2010

First Detectors

Jul

y !

Local Impacts

Leaves are stripped

Trees are stressed, susceptible to other

pests and diseases

Each caterpillar consumes 9 ft2 of

foliage!

Photo courtesy of Garrett (MD) County extension Office Garrett Co., MDRocky Arbor State Park, WI

First Detectors Landscape Impacts

Photo courtesy of Garrett (MD) County Extension Office

Garrett County, MD 2007

First Detectors Human Nuisance

First Detectors Where is Gypsy Moth Established?

Europe and north Africa (native) U.S. and Canada (invasive)

First Detectors Identifying Gypsy Moth

Egg Masses Caterpillars Pupae Adults (males vs. females)

First Detectors Gypsy Moth Life Cycle

First Detectors

Emergence

Each female lays one egg mass containing 500-

1000 eggs Overwinter in a protected

spot

Egg Masses(laid in late summer, hatch in late spring)

First Detectors

Spot the Egg

Mass

First Detectors

6 pairs of red spots

5 pairs of blue spots

Caterpillar (late spring through early summer)

First stage larvae

Larger caterpillars rest by day, feed at night

First Detectors

Gypsy moth 2”

Fall webworm

1”

Whitemarked tussock moth

1 1/3”

Yellownecked caterpillar

1 3/4”

Eastern tent caterpillar

1 3/4”

Forest tent caterpillar

1 3/4”

Spiny elm caterpillar

2”

Whi

tney

Cra

nsha

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MN

Dep

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Caterpillar Look-alikes

[full grown length in inches]

First Detectors Feeding Damage

Random feeding Entire leaf to midrib Can cover acres of woody habitat

First Detectors Host Preference

Preferredeaten by all stages of larvae

Oak, aspen, willow, white and river birch, basswood, larch, mountain-ash, alder and apple

Hawthorn, hazelnut, hophornbeam, hornbeam, serviceberry, witch-hazel

Less-preferredeaten only by older larvae

Yellow birch, boxelder, butternut, black walnut, cherry, eastern cottonwood, elm, hackberry, hickory, red and sugar maple, pine, and spruce

Blueberries, pin cherry, chokecherry, sweet fern

Avoidedrarely fed upon

ash, cedar, fir, silver maple, catalpa, mulberry and many urban species

Dogwood, elderberry, grape, greenbrier, juniper, raspberry, viburnum, and buckthorn!!

First Detectors

Pupa (Cocoon)(summer months)

Males smaller than females Attach by silken threads Found in protected spots

Bark crevices Duff layer

2 weeks

First Detectors

Adult(mid-summer to early fall)

Female(does not fly)

Male (daytime flier)

Distinct “commas” on top and underside of wings

Feathered antennae

First Detectors Mating Behavior

Females do not fly Pheromone attracts males Females lay one egg mass Adults die, eggs overwinter

First Detectors

Pheromone-baited traps Delta: sticky interior, trap holds ~10 males

Early Detection

Milk carton: kill strip, trap holds ~1000 males Male moths lured in as they try to find females

First Detectors

Trapping, Treatment and Regulations

Minnesota Dept. of Agriculture uses trends in moth numbers over time and space to determine treatment locations and where moths are established

First Detectors Gypsy Moth Trends in Minnesota

Main population is closer Mating success increasing

2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 20130

10000

20000

30000

40000

50000

60000

70000

535 391 1310 4123608

12255

27870

4242 565910445

71262

First Detectors

Larval ballooning

Populations expand 1¼ miles per year due to larval dispersal

Natural Artificial

Tourism

Nursery stock

Household moves

How Does Gypsy Moth Spread?

Life stages are transported by humans 13-16 miles per year