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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
2
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?
3
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
4
Stan
d D
evelo
pm
en
t ove
r time
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
5
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?
6
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
7
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
8
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
10
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
13
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
14
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
15
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
16
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
17
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
20
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
21
Sometimes it’s not so simple.
22
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
23
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
24
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: [email protected]