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Western Washington Forest Health

Amy Ramsey

Forest Pathologist, Forest Health

Olympia, WA

Forest Health at DNR

Provide technical assistance, monitoring, education, and research.

Forest Pathology – tree diseasesIncludes fungi, bacteria, viruses

Forest Entomology – tree insectsIncludes bark beetles, weevils, defoliating caterpillars, sucking insects (like aphids)

The Forest Health

program is

involved with

organisms and

events that:

Kill trees

Slow tree growth

Damage wood

products

Photo by G. Kohler

Photo by K. Zobrist

• Provide technical assistance on tree and forest health care for public and private landowners– State

– Farm

– County

– Woodland

– Municipal

– Urban managers

– Industrial

– Residential owners

Forest Health Program

Forest Health Program Services

• Forest health workshops• On-site prescriptions• Applied research• Cooperative studies• Demonstration sites• Annual detection

– Aerial survey– Ground surveys

• Annual Forest Health Highlights report

Forest Health at DNR

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Agenda

Forest Health and general tree healthconcepts

Identification & Management Foliar insects and diseases Weather related damage Dwarf mistletoes Bark beetles Root diseases Invasives

Where to get help with identification

What is a healthy forest?

• Well, it can be really simple and very complicated

Factors influencing Forest Health

1) Forest Ecosystem Processes

1) Nutrient cycling

2) Water transport and filtering

3) Wildlife habitat

2) Tree and forest resiliency to insects and diseases

3) Landowner objectives

What does a healthy forest

look like?

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Factors influencing Forest Health

1) Forest Ecosystem Processes

1) Nutrient cycling

2) Water transport and filtering

3) Wildlife habitat

2) Tree and forest resiliency to insects and diseases

3) Landowner objectives

Forest Ecosystem Processes

• Diseases and insects are a natural part of ecosystem; at low levels act as

– thinning agents

– recyclers

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Stan

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Forest Ecosystem Processes

• Diseases and insects are a natural part of ecosystem; at low levels act as

– thinning agents

– recyclers

• Diseases and insects cause structural and functional changes

– in individual trees

– in forest areas

Factors influencing Forest Health

1) Forest Ecosystem Processes

2) Tree and forest resiliency to insects and diseases

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1. living tissue

2. fine root and leaf production

3. flower and seed production

4. height, branch, root growth; scar tissue

5. diameter growth and resistance to insects

and disease

Priorities for Tree Growth Vigorous trees can resist insects and pathogens

Vigorous trees can recover from damage or disease

Adventitious root growth

Fire scorched

ponderosa

pine

What might caused a tree to be stressed?

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Factors influencing Forest Health

1) Forest Ecosystem Processes

2) Tree and forest resiliency to insects and diseases

3) Landowner objectives

Landowner Objectives

• What are they?

• They drive decisions for management of diseases, insects and abiotic damaging agents

Factors influencing Forest Health

1) Forest Ecosystem Processes

2) Tree and forest resiliency to insects and diseases

3) Landowner objectives

What are the clues?

Note damage and trees affected.

Note signs and symptoms.

Look for pattern to damage development.

Look at the big picture over the site.

Incorporate personal or local knowledge.

Steps to Diagnosis:

Root disease

Needle Cast

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Symptoms and Signs• Symptom: effect of the organism causing

damage

• Sign: the actual organism

White pine blister rust

Symptoms and Signs

• Symptom: effect of the organism causing damage

• Sign: the actual organism

Laminated Root Rot

Thinning crown (left)

Ectotrophic mycelium

(white on root)

The disease triangle is integral for understanding tree diseases.

Different diseases and insects can affect different parts of the tree.

Foliar

diseases

Root and

butt

diseases

Bark Beetle MortalityBark Beetle MortalityBark Beetles

• Attack trees weakened by competition, defoliation, drought, root disease, and fire

• Are generally tree host and size specific

• Damage occurs rapidly, but is not immediately APPARENT

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Recent attack: dead

Current attack: essentially deadBark Beetles – general biology

• Focus initial attack on weak or injured trees

• Can switch to a coordinated mass-attack of nearby vigorous trees

Bark Beetles – general biology

• Feed on phloem

• Locate and attack susceptible trees (host volatiles)

• Use complex pheromone communication

Bark beetle adults

• Hard-bodied, cylindrical beetles• Brown to black• 1-9 mm in length• Elbowed, clubbed antennae

Ecological Roles of Bark Beetles

• Affect plant succession

– kill mature, weakened or damaged trees

• Influence nutrient turnover

• Create wildlife habitat

– Snags - cavity nesting birds, bats, etc.

– Openings – browse for big game animals

• Effects on stand structure and composition

• Increase potential for wildfire

Mountain pine beetle outbreak in Canada. Cumulative affected area is 52,000 square miles or 73% of Washington State.

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Douglas-fir Beetle

• Hosts: Douglas-fir, may kill western larch

• Breeds in felled, injured or diseased trees, resulting in widely scattered mortality

• Epidemic populations kill apparently healthy trees over extensive areas

Douglas-fir beetle

• Early symptoms

– Boring dust

– Pitch streams

• Late Symptoms

– Red crown

– Pouch fungus

Douglas-fir beetle Douglas-fir beetle management

• Maintain tree vigor

• Don’t injure stems or roots

Douglas-fir beetle management

• Salvage blowdown and any infested trees before two springs pass

Douglas-fir beetle management

• MCH repellant can be used to protect high-value trees

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Root Diseases Root diseases are

commonly caused by

fungi

Not all fungi cause root

diseases

Water and

mineral uptake

from soil

Water and minerals

up the tree

Light

Sugars formed

from photosynthesis

Sugars

down the tree

into roots

• Eliminates

maladapted trees

• Creates openings for

regeneration and

succession

• Decomposes organic

matter and recycles

nutrients

In natural forests, even pathogenic species can

play a beneficial role.

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Compromise structural integrity of roots and base of tree

Reduce growth

Cause mortality

Increase tree susceptibility to windthrow and insect damage

Root Diseases: Pathogenic fungi kill single trees or large pockets of trees many hectares in size

• Root disease centers are usually localized.

• All sizes of susceptible trees can be affected.

Diffuse or scattereddistribution

Discrete pocket

If a visual assessment indicates more than 5% occurrence, conduct a formal survey to determine its distribution and severity.

Root Disease Symptoms – Landscape Scale

Root disease patches have trees in

various stages of decline next to

seemingly healthy trees.

• Snags

• Trees with no

fine branches, no

foliage

• Trees with fine

branches, no

foliage

• Trees with

thinning foliage

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Other forest level

symptoms may include:

Openings are

invaded by brush

and non-host species

Other stand level symptoms may include:

• Trees with chlorotic foliage• Trees with stress cone crops• Trees with thinning foliage• Rounded tops of crowns

Other forest or site level symptoms may

include:

Dead trees next to stumps

Other site level symptoms may include:

Trees broken at the stem• Basal resinosus

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Armillaria root disease

Laminated root rot

Annosus root disease

Schweinitzii root disease

The Most Common Root Diseases

Phytophthora root diseases

Next steps for identification

– Obtain root disease reference materials from misc. resources (see handout)

– Look around at stumps and/or fallen trees

– Excavate major root and base of tree

Excavating tree

roots and

looking for root

disease fungi

Above ground

Below ground

Schweinitzii root disease

Phaeolus schweinitzii

– Velvet top fungus

Old Douglas-fir & Sitka spruce, most common hosts

Armillaria root disease

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White mycelial fansBasal

resinosus

Rhizomorphs

Laminated Root

Rot

Fungus:

Phellinus

sulphurascens

(Phellinus weirii)

Host: most

commonly

Douglas-fir

Landscape level

symptoms:

Forest unit with

laminated root rot.

Notice dead trees in

overstory.

Understory

development of

resistant or immune

species.

Western red

cedar

Bigleaf maple

Tree host

susceptibility

to laminated

root rot:

Highly susceptible:

Douglas-fir

Grand fir

Mountain hemlock

Intermediately susceptible:

Western hemlock

Western larch

Tolerant:

Lodgepole pine

Western white pine

Resistant:

Ponderosa pine

Western redcedar

Immune:

All hardwoods are immune

Alder

Bigleaf maple

Laminated root rot

affected areas will

likely have some

downed trees

present.

Few to no roots

present. No fine

roots

Delamination

decay pattern in

remaining roots

Setal hyphae,

red whiskers

Ecotrophic

mycelium

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Ectotrophic mycelium

Hollow stumps

Laminated Root Rot Signs

Hollow, decayed stumps

Laminated Root Rot

Signs – Setal hyphae,

red whiskers

• Staining in stumps

Fungus spreads primarily through and along roots.

Annosus Root Disease

Fungi: Heterobasidion occidentale

Heterobasidion parviporum

(Heterobasidion annosum)

Hosts:

• Coniferous– True firs– Douglas-fir– Western hemlock– Sitka spruce– Western red cedar

• Hardwoods– Bigleaf maple– Alder

Characteristics of Fungus

• Fruiting bodies

– Bracket-type fungus

– Dark upper surface with white to cream margin

– Porous lower surface

• Irregular pores

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Heterobasidion Infection

• Fruiting body spores

– Distributed by wind

– Cause new infections on freshly cut stumps

Stump staining White decay with black flecks Hollow stumps

General management recommendations for root diseases

Right tree in the right place

Avoid damaging roots or stem

of tree:

- soil compaction

- construction damage

- landscaping equipment

damage

- severing roots

Learn to recognize the disease

Survey- where is it?

Keep records on it’s location

Maintaining high tree vigor

Root disease management options

Replant non-susceptible species

– Alternative species: plant or encourage least susceptible species

• Match seed zone of stock to site

• Expect some mortality unless planting completely resistant or immune species

• Plant right tree in the right place

Cut buffer around root-rot pocket

Stump removal or push-over logging

Apply Borax based stump treatment

Do nothing

Root Rot management options – in a

forestry setting

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Dead and dying trees

Asymptomatic trees –may or may not

be infected

Defoliators and

Needle Casts

Defoliators of Deciduous Trees

Forest tent caterpillar defoliation of red alder, July 2009

Same stand, October 2009Photos: Mike Johnson, WADNR

Tent caterpillars

• Native

• Cyclical

Forest tent caterpillar.Photo: Mike Johnson, WADNR

Foliar damage:Disease or

something else?

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Look close. What are the clues?

Needle Casts

Dothistroma Lophodermella Lophodermium

Dothistroma

LophodermiumLophodermella

Swiss Needle Cast

• Native foliar disease• Host: Douglas-fir• Chlorosis (yellowing) and premature “casting”

of older needles• Starts in lower branches and works its way up

• Severely infected trees may have only current year needles

• Most visible in young plantations (tree farms, etc.)

Swiss Needle CastPhaeocryptopus gäumannii

Pseudothecia (fruiting bodies) erupting from stomates of Douglas-fir needles

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Keithia Blight

Fungus:

Didymascella

thujina

Host: western red

cedar (Thuja

plicata) and

cultivars

Management strategies for foliar diseases

Fungicides can buy protection on a yearly application

basis

product and timing depend on pathogen (lifecycle,

weather conditions)

Prune or thin to keep airflow at a maximum if foliar

issues occurring

If pruning, prune in late fall or winter to avoid other

disease and insect issues

Right tree in right place

avoid planting offsite species (offsite seed source

or offsite species in wet or drainage areas)

Cedar Flagging• Western red cedars

• Usually visible in late summer and fall

Fall Yellowing• Older needle drop

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Red Belt/Parch Blight Needles damaged uniform distance on

tip. No fruiting bodies. Position that is exposed to dry or cold

winds.

Drought

• Many species affected, but some more susceptible than others

• Injury from the top-down and outside-in

• Needles and softest tissue appear shrunken

• Roots dry but healthy looking

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Sometimes it’s not so simple.

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Exotic pests are bad

White pine blister rust

Dutch elm disease

(photo from Britannica web)

Port Orford Cedar root disease

Phytophthora’s as root diseases

Host: Port Orford Cedar

(Chamaecyparis lawsoniana)

Fungus: Phytophthora lateralis

Fungus: Cronartium ribicola J. C. Fisch.Division: Basidiomycota

Non-native

Aecial

host

Ribes

Castilleja

Pedicularis

*

Aecial Host, 5 needle Pinus:

◦ Bristlecone pine (P. aristata)◦ Eastern white pine (P.

strobus)◦ Foxtail pine (P. balfouriana)◦ Great basin mountain

bristlecone pine (P. longaeva)

◦ Limber pine (P. flexilis)◦ Southwestern white

pine (P. strobiformis)◦ Sugar pine (P. lambertiana)◦ Western white pine (P.

monticola)◦ Whitebark pine (P. albicaulis)

Western White Pine (Pinus monticola Dougl.)

◦ 5-needle pine- foliage bluish green

with whitish tinge- 5 to 10 cm long

◦ Seed cones- cylindrical- 10 to 25 cm long

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Programs evaluating natural genetic resistance and

developing resistant seed:

◦ USDA Forest Service Pacific NW Region

- Dorena Genetic Resource Center

- began 1960’s

Short-term artificial

inoculation trials

Multi-site field trials

Western white pine, WPBR, field trials in western Washington:

◦ Established in winter 2006/2007 (~ 5 yrs old)

◦ 6 sites

◦ ~ 3 acres in size

◦ 1269 – 1365 trees at each site

Origin of seedlots:

◦ Washington- Gifford Pinchot NF- Mt. Baker/Snoqualmie NF- Olympic NF- Wenatchee NF- Colville NF

◦ Oregon- Mt. Hood NF- Umpqua NF- Confederated Tribes of

Warm Springs◦ British Columbia◦ Idaho

- Bingham seed orchard

The parent trees for the seedlots originated

from wide geographic sources, including the

Gifford Pinchot, Mt. Baker/Snoqualmie

Olympic, Wenatchee, and Colville National

Forests in WA; the Mt. Hood and Umpqua

National Forests in OR; the Confederated

Tribes of Warm Springs (OR); British

Columbia; and Idaho (a F2 orchard lot from

Bingham seed orchard). The seedlots planted

include some with major gene resistance

(from Cr2 gene), some with partial resistance,

and a susceptible control.

◦ Vigor - Alive and vigorous- Alive and sickly- Recently dead

◦ Number of bole infections

◦ Total number of cankers- Normal- Partial bark reaction- Bark reaction

White pine blister rustmanagement options

• Pruning

• Planting genetically enhanced seedlings

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Tree diseases may be working in concert with other disturbance agents. Factors influencing Forest Health

1) Forest Ecosystem Processes

2) Tree and forest resiliency to insects and diseases

3) Landowner objectives

-Right tree in the right site

-water

-sunlight

-growing space

-Generally greater stress

on trees moving forward

- consider species

-more water needed

-less water available

General Tree Disease Management Recommendations

-Develop vegetation

management plants for

moving forward

-Individual trees

-Urban forests

-Green belts

Conclusions

Lot’s of biotic and abiotic tree damaging agents

Know the common ones and know where to

report the unusual

-Get help with identification if unsure

-Get help with agent specific management

options

Overall tree stress is likely to increase with

warmer, drier conditions

-Likely increase in root

disease damage

Expect the unexpected

moving forward

Please feel

free to contact

me with

questions.

Amy Ramsey

Phone: 360-902-1309

Email: amy.ramsey@dnr.wa.gov