John Kabashima, Ph.D.UC Cooperative Extension

Tim Paine, Ph.D.UC Riverside, Dept. of Entomology

Regional Impact of

PSHB and

Emerging Tree Pests

Pre-entry(laws & agreements)

Port-of-entry(inspection)

Rapid-response(response crews/regional containment)

Protecting Hawai‘i

World’s Biota Arrivals Escapes

Options: -Do nothing

-Regional containment

-Protect high value areas

-Biocontrol

Widespread

Options: -Do nothing

-Eradication

-Regional containment

Port-of-entry(inspection)

Rapid-responseReduced Budget-response

(response crews/regional containment)

Protecting Hawai‘i

Arrivals Escapes

Options: -Do nothing

-Regional containment

-Protect high value areas/trees

-Biocontrol

WidespreadLos AngelesOrangeSan Diego

Options: -Do nothing

-Eradication

-Regional containment

Polyphagous Shot Hole Borer

Some species beset by strong Alleeeffects could be less successful as invaders.

Exotic and Invasive Insect Species Implications

P. Tobin et al, 2011

The frequency of the lag phenomenon in invasions implies that at least some existing non-native species that are currently having little or no impact will eventually have much greater ones.

PSHB/FD and the Lag Phenomenon

Daniel Simberloff

Generations

5 10 15 20

Num

ber o

f ent

ry h

oles

per

tree

0

20000

40000

60000

80000

100000

5 daughters per female per generation

Growth of entry hole number per tree when a single female initiates the population at generation 1 and 5 daughters/

generation/mother remain on tree

Richard Stouthamer

This is what a tree with 38,000 entry holes looks like

• Box elder at Huntington Gardens about 2.5 years after first decline was detected

Richard Stouthamer and Dan Berry

Regional Impact of

PSHB

*

Current distribution of infestation of PSHB/FD

20122013

*

Current distribution of infestation of PSHB/FD

201220132014

*

Current distribution of infestation of PSHB/FD

2012201320142015

USDA FS Distribution trapping

Tom Coleman, USDA Forest Service

Pest Vulnerability Matrix • Minor pests

– Insects or diseases that do not cause damage requiring management action, but may still be observed on trees. These pests can be safely ignored.

• Exotics under classical biological control– Ash Whitefly 100 on 1 to 1 on 100– Gonipterous Weevil

• Low – Low severity = causes little damage and only seldom requires management action in urban

landscapes • Moderate

– Moderate severity = damage is unsightly or will lead to problems over time • Severe

– Severe = almost always lethal to the tree (directly or indirectly)• Recent or Quarantine Pests

– Recently introduced or Quarantine pests that may or may not pose a threat to the landscape

• Emerging pests– Pests not yet detected in California. This category is important when adapting the planting plan

to account for likely future pests.

Greg McPherson, PhDDirector, Center for Urban Forest ResearchPSW, USDA Forest Service

Nursery•Potential to transport•Economic Impact

• Shipment Protocols

Urban Landscape•Incubator

•Threat to Urban Forest

Avocado• PSHB and Fusarium

A major threat

Polyphagous Shot Hole Borer (PSHB)

Natural/Riparian• Major threat to native trees•Important Alternate Host

•Ecological Impact

Regulatory•Pathways•Regulations•Pesticide Use•Water Runoff

2012 2015

Tree Species Attacked by Beetle 286 303

Tree Species Infected by Fungus 117 138

Agricultural Crops 13 13

California Native Tree Species 11 18

Number of Tree Families 62 64

Number of Reproductive Hosts 19 37

Host Range FD/PSHB

3. Evergreen Maple (Acer paxii)4. Trident maple (Acer buergerianum)5. Japanese maple (Acer palmatum)6. Castor bean (Ricinus communis)7. California sycamore (Platanus racemosa) *8. Red willow (Salix laevigata) *9. Avocado (Persea americana)10. Mimosa (Albizia julibrissin)11. English Oak (Quercus robur)12. Coast live oak (Quercus agrifolia)*13. London plane (Platanus x acerfolia)14.Cottonwood (Populus fremontii)*15. White Alder (Alnus rhambifolia)*16.Titoki (Alectryon excelsus)17. Engelmann oak (Quercus engelmannii))*18. Cork Oak (Quecus suber)19. Valley oak (Quercus lobata) *20. Coral tree (Erythrina corallodendon)21. Blue palo verde (Cercidium aculeata) *22. Palo verde (Parkinsonia aculeata)23. Moreton Bay Chestnut (Castanospermum australe)24. Brea (Cercidium sonorae)25. Mesquite (Prosopis articulata)*26. Weeping willow (Salix babylonica)27. Chinese holly (Ilex cornuta)28. Camelia (Camellia semiserrata)29. Acacia (Acacia spp.)30. Liquidambar (Liquidambar styraciflua)31. Red Flowering Gum (Eucalyptus ficifolia)32. Japanese wisteria (Wisteria floribunda)33.Black Cottonwood (Populus trichocarpa)*34. Goodding’s black willow (Salix gooddingii)35. Goodding's black willow (Salix gooddingii)*36. Tree of heaven (Alianthus altissima)37. Kurrajong (Brachychiton populneus) 38. Black Mission Fig (Ficus carica)

Eskalen, A., Stouthamer, R., Lynch, S.C., Rugman-Jones, P., Twizeyimana, M., Gonzalez, A., Thibault, T. 2013. Host Range of Fusarium Dieback and its Ambrosia Beetle (Coleoptera: Scolytinae) Vector in Southern California. Plant Disease.In 97:7, 938-951

Benefit Cost Ratio of Urban Forests• Urban Forest

– Private– Street and Park Trees

• Ecological Services– BMP to control stormwater– Energy savings

• Mitigate heat-island and clean air in cities– Atmospheric CO2 reduction– Air quality benefits– Aesthetics and other benefits– Ecosystem benefits

• Habitat for animals and plants• Food for animals• Cycle water and nutrients through ecosystems

Benefit Cost Ratio of Urban Forests• Structure, function and value of street and park trees in 5

cities.– Fort Collins, Co.– Cheyenne, Wy.– Bismarck, N.D.– Berkeley, CA.– Glendale, Az.

• Cities spent $13–65 annually per tree, benefits ranged from $31-89 per tree.

• For every management dollar invested, benefits returned annually ranged from $1.37-3.09

McPherson, et al. 2005

PSHB Impacts• Decrease or Loss of Ecological Services• Cost of:

– Treatment– Pruning– Removal $(650 to $1000 per tree)

• Chipping• Stump grinding• Handling and disposal

– Transport– Compost– Alternative Daily Cover– Biomass Electrical Generation

WILL HOMEOWNERS DO OR BE ABLE TO AFFORD THIS?– Injury Hazards from falling and weakened limbs

PSHB Impacts

– Municipal Tree Inventory • 29 of 34 Cities• 10 Misc (school districts, water departments, HOA)

– 83, 064 Sycamores

–APPROXIMATE VALUE = $250,176,772.10

Earth has about 3.04 trillion trees, but humans have cut down nearly that many too.

The planet loses about 15 billion trees a year, with only 5 billion of them being replaced.

Thomas Crowther, Yale School of Forestry and Environmental Studies

Tree Removal

Tree Autopsy

Tree Autopsy

Canker revealed under bark Closeup of canker

PSHB/FD Structural Damage to Branch

Falling branch hazard and to arborists when climbing trees

IPM/Plant Health/BMPs– EradicationTactics

CulturalPhysical

(detectiontraps)

Mechanical(chipping, burying)

Biological

Pest ControlTactics

Pesticides

Control OptionsCultural / Sanitation

• Tree removal• Pruning infested branches• Pruning wound protection• Chipping, Solarization/ fumigation• Restrict firewood movement

Chemical• Beetle and/or Fungal Symbionts• Trunk sprays • Systemic-Soil injection/drench, trunk injection

Attract & Kill Traps • Lure and Pesticides

Biocontrol • Natural Enemies• Use of Entomopathogen Fungi• Use of Endophytic bacteria and/or fungi

GSOB Incident Action Plan• Survey and Detection

– Delimitation– Outside of known infestations– Develop procedures and fund reporting and identifying

new infestations– Maintenance and location of data base

• Based on Pest Rating and Damage– Restrict movement of pest infested material– Develop policies and identify agencies and stakeholders– Identify how it is moving and how and who will regulate

• Develop and Implement a Management Plan• Identify Research Needs

Incident Action PlansExotic Pest Research Needs

• Identify Short, Medium and Long Term Needs– Positively identify pest

• Is it a known or undescribed species– Determine country of origin– Conduct studies on it’s biology

• Life cycle• Hosts

– Agriculture, urban forests, natural ecosystems• Flight

– Best Management Practices• Cultural, mechanical, physical, chemical, biological• BMPs for homeowners, commercial landscapes and municipalities

Akif Eskalen1, R. Stouthamer2, P. Rugman-Jones2, S. Lynch1, T, Paine2, M, Jones2, J. Morse2, F. Byrne2, T. Coleman3,

J. Kabashima4, M. Dimson4, T. Thibault5, D. Berry5, S. Drill6., F. McDonogh7, J. Mayorquin1, F. Na1, J. Carrillo1,

S. Feirer7,

1 Plant Pathology and Microbiology, UC Riverside2Entomology, UC Riverside

3USDA Forest Service4UCCE Orange County

5Huntington Botanical Garden6UCCE Los Angeles County

7UC ANR

Current studies on Polyphagous shot hole borer/Fusarium dieback

• California Avocado Commission• USDA Farm Bill• Huntington Gardens• Hofshi Foundation• USDA Forest Service• CDFA Specialty Block Grants• OC Parks• California Association of Nurseries and Garden Centers• Nursery Growers Association• University of California Irvine

Work Funded By

• RPW Services, Inc.• West Coast Arborists• Great Scott Tree Services, Inc.• Target Specialty Products• NuFarm/Valent• ArborJet• Mauget• FMC

Donations and Collaborators

? Questions?

Elephant WeevilOrthorhinus cylindrirostris