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‘One beetle too many’ The emerald ash-borer threatens Fraxinus trees in Europe

Brigitta Wessels, Ernst-Jan Scholte14 December 2007

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Emerald ash borer (Agrilus plannipennis) Coleoptera: Familie Buprestidae

• Adults • length: 7.5 to 15.0 mm• Body : narrow , elongate• Colour: coppery-green• Eyes: large, kidney-shaped

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Larvae are flatheaded borers 4 larval stagescreamy white in colour

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Es (Fraxinus spp.)

Host: Es

Es (Fraxinus spp.)

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Es (Fraxinus spp.)

Female lays eggs on bark

Life cycle Agrillus planipennis

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Female lays eggs on bark

Larvae develop in wood (1-2 years)

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Female lays eggs on bark

Adults emerge, live for 2-3 weeks

Larvae develop in wood (1-2 years)

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Female lays eggs on bark

Adults emerge, live for 2-3 weeks

Larvae develop in wood (1-2 years)

Mating

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Host Range:

• Fraxinus spp. (In Dutch: es)• Fraxinus americana (white ash)• F. nigra (black ash)• F. pensylvanica (downy ash)• F. chinensis• F. lanuginosa• F. mandshurica (Japanese ash)• F. rhynchophylla• F. japonica• F. nigra• F. excelsior

• Some species of Ulmus (elm), Juglans (walnut), Pterocarya (japanese wingnut)

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Original distribution: Eastern Asia (Russian Far East, China, Japan, Korea, Mongolia, Taiwan)

Introduced into:- Canada (Ontario, 2002)- USA (Michigan 2002, Ohio 2003, Maryland 2003,

Virginia 2004, Indiana 2004, Illinois 2006, Pensylvania 2007- Russia:Moscow 2007

Distribution:

USA

Canada

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Symptoms of infestation

1) Crown dieback/chlorosis2) Epicormic shoots3) Bark deformities4) Foliage feeding5) Larval galleries6) Emergence holes

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2 3 5 6

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Different shaped exit holes

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Larvae mine in stem and twigs

disrupts transport of nutrients

weakening of the tree

trees dies after ± three years

Damage:

Affected number of ash trees:

In the USA more than 25 million.

In the Canada (Essex, Ontario): 100.000.

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Control methods:• Insecticides • Cut, chip and burn • Ash free zone around infested area • Don’t move infested wood material

Preventive measure: • preventive survey (PPS 2006,2007,2008)

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Risk for Europe

• Agrilus plannipennis not present (yet?)• The species would be able to survive and

have economic impact in many parts of Europe

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Distribution of Fraxinus excelsior (In Dutch: gewone es)

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Risk for Europe• Agrilus plannipennis not present (yet?)• The species would be able to survive and have

economic impact in many parts of Europe• Control would be very difficult to achieve• Based on these factors, Agrilus planipennis

has a quarantine status A1 for Europe• Import in Europe of packaging ash wood and

living ash trees is a minimum

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Thank you for your attention