Forest Pests

Forestry & Society

Fall 2003

J.G. Mexal

Forestry & Society

Trees Live A Long Time/PNW,2000

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Human PaperBirch

WhiteSpruce

PonderosaPine

SitkaSpruce

Redwood

Lifespan (yrs)

Forestry & Society

Forest Health/PNW,2000

“A healthy forest can renew itself vigorously across the landscape, recover from a wide range of disturbances, and retain its ecological resilience while meeting current and future needs of people for values, uses, products, and services.”

USDA Forest Service, 1997

Forestry & Society Pest Outbreak Triangle/PNW,2000

Forestry & Society

Forest Pests-

• Exotic Pests

• Native Pests

• NM Pests

Forestry & Society

Forest Pests-Pest Species Migration

• 1869: Gypsy moth – Asia?-- E. Hardwoods

• 1898: White pine blister rust -- Europe to Idaho to NM -SW white pine

• 1904: Chestnut blight -- Japan –

American chestnut (50% mortality by 1930)

• 1929: Dutch Elm Disease -- Europe –

American Elm (77 million killed in 20th century)

• 1980s: Asian long-horn beetle -- China – E. hardwoods

• 1990s: Pinewood nematode -- Japan -- Western conifers

American chestnut-• Occupied 25% of

Appalachian hardwood forest

• Largest DBH = 17 ft

• Japanese chestnut imported by Bronx Zoo in 1904

• Not TES because of stump sprouts

• Susceptible to P. cinnamoni

Original Distribution

Forest PestsChestnut Blight - Dryphonectria parasitica

• From Japan 1904 • Eliminated American chestnut from

eastern deciduous forests.• Annual lost timber value for 3 states of

$683.9 million (1999 dollars). • Caused declines in chestnut-dependant

wildlife and erosion where lost trees have not been replaced.

American chestnut- a comeback?Original Distribution

Forest PestsWhite Pine Blister Rust Cronartium ribicola

Late 1800’s throughout range of eastern white pine andearly 1900’s in 6 western. Killing pines in western high elevation ecosystems, eliminating wildlife forage; affecting soil stability, snowmelt.

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1935Current

Forest @ risk

Forest PestsWhite Pine Blister Rust Spread

Historic

Current

Dutch Elm Disease- Ophiostoma ulmi

• Discovered in 1930 from Europe

• Occurs in most states. Killed more than 60% of elms in urban settings.

• A more virulent U.S. strain evolved and has caused significant impacts in Europe.

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•Lymantria dispar brought to Boston, MA in 1869 for silkindustry .•Infests 15 states in NE US•Feeds on oak, sugar maple,beech and aspen

Forestry & Society

Forest Pests-Gypsy moth

Gypsy moth found in Travis Co., TX/2005

Asian gypsy moths such as this male, left, and female attack more than 500 plant species.

•In 19 states, spot infests 12 more.•Annually defoliates millions of northeastern and Midwestern forested acres; •Suppression costs tens of millions. •Record losses in 1981: 13 million acres defoliated; $3.9 billion (1998 dollars) in losses.

Forestry & Society Emerald Ash Borer (Agrilus planipennis)

Imported from AsiaInfested Canada, MI (1999) & OH & MDKilled 6kk trees in MI alone (2002-2004) David Cappaert

Could cause elimination of ash as a street, shade, and forest tree nationwide at an estimated cost of $282 billion.

Forestry & Society Emerald Ash Borer (Agrilus planipennis)

D.G. McCullough, Tree Farmer (Mar/Apr 2006)

• Discovered in 2002• All ash species susceptible• 12-15kk ash trees killed in

central MI by 2006• Threatens 8kkk forest trees

(valued @ $282 billion)• Threatens 3.8kkk urban trees

Photos by David Cappaert

Exotic Pests

• Emerald Ash borer:– Established in Michigan in 2002

– Established in Ohio in 2003

– Established in Indiana in 2004

– Established in Illinois in 2006• Area = 40,000 square miles

• 3 billion trees vulnerable

• Removal & replacement costs ~ $7 billion

Forest Pests Sudden Oak Death = Phytophthora ramorum

Joseph O'Brien

http://www.invasivespecies.gov

•Discovered in 1994 in CA•In 2005, spread to OR, WA, GA, LA, TN, SC•In 2006, found in 22 states•84 susceptible species in US

•Calif. black oak•White fir•Calif. red fir•Coastal redwoods•Coast live oak•Douglas-fir•Madrone•Tanoak

•Could devastate oak forests nationwide.

Forestry & Society Exotic Pests/Balsam Woolly Adelgid/ PNW,2000

Native to Western EuropeDiscovered on West Coastin 1929

Subalpine fir 1965

(Adelges piceae) 1908 Attacks true fir species. Caused dramatic declines in Fraser fir inGreat Smoky Mountains National Park, resulting in understory andwildlife changes.

Forestry & Society Exotic Pests/Hemlock Woolly Adelgid/

(Adelges tsugae) 1920’s from Asia. Currently in more than 4 states. Contributing to decline of eastern and Carolina hemlocks. Alters bird communities where it kills eastern hemlock.

Forestry & Society

Forest Pests-Asian Longhorned Beetle

Photos by M. Smith

Nebraska Forestry Service

Pinus sylvestris

Forestry & Society Pine Knot Nematode on Scots Pine

• Native to Japan

• Discovered in 1979 in MO

• Carried by pine sawyer beetle

• No control

SNC Aerial Survey /Greg Filip

1996 1997

Forestry & Society Exotic Pests/Weeds Science Findings 38/Oct’01

• SE

kudzu

cogongrass• NW

English ivy

Holly

Scots broom

Himalayan blackberry

Sweet cherry

Forestry & Society Exotic Pests/Weeds Science Findings 38/Oct’01

• SE

kudzu

cogongrass

• NW

English ivy

Holly

Scots broom

Himalayan blackberry

Sweet cherry

Forestry & Society Exotic Pests/Weeds Science Findings 38/Oct’01

• SEkudzucogongrass

• NWEnglish ivyHollyScots broomHimalayan

blackberrySweet cherry

Forestry & Society Exotic Pests/Weeds

Yellow starthistle competes with mariposa lily

PNW Sci. Update 9:2:Mar’05

Forestry & Society Exotic Pests/Weeds Science Findings 38/Oct’01

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Old GrowthControl

Old GrowthVDT

ThinnedControl

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NativesExotics

Cover (%) after 3 yrs

TreatmentVDT = Variable density thinning

2nd Growth Douglas-fir

VDT createsopenings forinvasion byexotics

Forestry & Society

Forest Pests-

• Exotic Pests

• Native Pests

• NM Pests

Forest Pests

Mountain Pine Beetle

British Columbia•Started in 1998

•Attacked Lodgepole pine•Area = 9 kk ha •Value = $9kkk

•2007:•Area = 15,000,000 ha•Volume = 530 kk m3

•Value = $38 kkk•40% of BC pine forest

Ministry of Forests

1 m3 = 1 telephone pole

Will climate change spell the end of forests in North America?

A warmer climate allows the beetle to migrate north and potentially east and then south!!!

Forest Pests

Mountain Pine Beetle

Spruce beetle spread in Kenai Peninsula, AK/ van Hees PNW-RP-563, ‘05

Forest Pests

Spruce Bark Beetle J. For. 104(5):254:’06

• Beetle-killed spruce in Alaska

• Over 1 million acres destroyed (90% mortality)

Bark beetle outbreaks in Texas/ SJAF 27(2):122:2003

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Managed - Controlled

Wilderness- No Control

Infested Acres

Chemical controldoes not work! It’s

too late!

Forest Pests

Billboard in Florida/ J. For. 104(5):241:2006

Forestry & Society

Forest Pests-Western Spruce Budworm

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Millions of Acres

Choristoneura occidentalis is native to Rocky Mountains.Feeds on Douglas-fir and true firs.

Forestry & Society

Forest Pests-Oak Wilt

• Oak wilt = Ceratocystis fagacearum– oaks (Quercus)-- 36 species

– chestnuts (Castanea)

– chinkapins (Castanopsis)

– tanoak (Lithocarpus)

J.For. 99(5):4:’01

Discoveredin 1995

Forestry & Society

Forest Pests-Oak Wilt

Healthy

Dead

J.For. 99(5):4:’01

Forestry & Society

Forest Pests-Oak Wilt in Texas

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J.For. 99(5):4:’01

Cost ($1,000s)

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Red-Headed Pine Sawfly

• Enemy of young pine plantations

• Usually completely defoliates a tree before crawling to the next

• Destroys trees because there is more than one generation of eggs laid

Forestry & Society

Forest Pests-USFS Expenditures

• Insects– Gypsy moth $3.8 million

– Mtn pine beetle $1.1 million

– So. pine beetle $ 315,000

– Hemlock woolly adelgid $ 116,000

– Ips beetle $ 42,000

– Spruce beetle $ 10,000

• Weeds $ 285,000

• Disease (oak wilt) $ 270,000J.For. 99(5):4:’01

Forestry & Society

Forest Pests in New Mexico• Bark beetles

– Dendroctonus – Ips – Twig beetle

• Wood borers– Roundhead – Flathead

• Mistletoe– True (Phoradendron) – Dwarf (Arceuthobium)

• Western Spruce budworm• Tent caterpillar• Cytospora canker (aspen and willows)• Douglas-fir tussock moth• White pine blister rust

• Describe the pest outbreak triangle

• Why and how do these exotic pests get introduced and started?

• What are the major forest pests in the US? In NM?

• How are they controlled? Does it make sense? Why?

Forestry & Society

Forest Pests- Review Questions