Diseases
302 diseases tracked across Western Washington landscapes, with host plants, symptoms, and management.
Showing 302 diseases
Alkali Yellows
Alkali yellows
Affects 2 plants
Alternaria Fruit Rot
Alternaria spp
Affects 12 plants
Angular leaf spot
Pseudomonas syringae pv. lachrymans
Affects 1 plant
Annosus Root Rot
Heterobasidion annosum (syn. Fomes annosus)
Affects 20 plants
Anthracnose
Various species including Colletotrichum acutatum, C
Affects 180 plants
Anthracnose (Bull's-eye Rot)
Cryptosporiopsis curvispora
Affects 16 plants
Anthracnose and Bull's-eye rot
Neofabraea spp. (N
Affects 14 plants
Anthracnose Blotch
Ophiognomonia leptostyla (syn. Gnomonia leptostyla)
Affects 5 plants
Apple Mosaic
Apple mosaic
Affects 12 plants
Apple Proliferation
Apple proliferation
Affects 12 plants
Armillaria Crown and Root Rot
Armillaria mellea
Affects 36 plants
Armillaria Root Rot
Armillaria ostoyae
Affects 466 plants
Ascospora Dieback
Seimatosporium lichenicola
Affects 14 plants
Bacterial Blight
Pseudomonas syringae pv. syringae
Affects 124 plants
Bacterial blight (Leaf spot)
Pseudomonas syringae pv. viburni or Xanthomonas spp.
Affects 30 plants
Bacterial Blights
Pseudomonas syringae
Affects 0 plants
Bacterial Cane Blight
Affects 8 plants
Bacterial Canker
Pseudomonas syringae pv. syringae
Affects 51 plants
Bacterial Leaf Spot and Blast
Pseudomonas syringae
Affects 8 plants
Bacterial Leaf Spot and Dieback
Pseudomonas syringae
Affects 45 plants
Bacterial Leaf Spots
The OSU Plant Clinic has found many leaf spots due to the...
Affects 0 plants
Bacterial twig blight
Pseudomonas syringae (bacterial)
Affects 14 plants
Bacterial Wetwood Slime Flux
Affects 8 plants
Berckmann's Blight
Affects 3 plants
Bigleaf Maple Decline (Bigleaf Maple Dieback)
Affects 45 plants
Bitter Pit
Non-pathogenic (calcium deficiency)
Affects 14 plants
Black Canker
An uncharacterized
Affects 36 plants
Black Knot
Apiosporina morbosa
Affects 38 plants
Black Mold
Chlaropsis thielavioides
Affects 12 plants
Black Root Rot
Affects 42 plants
Black Root Rot Complex
Complex of Rhizoctonia fragariae, Cylindrocarpon spp., Py...
Affects 2 plants
Black Spot
Diplocarpon rosae
Affects 11 plants
Black-Stain Root Disease
Leptographium wageneri
Affects 4 plants
Blackline
Affects 6 plants
Bleeding Canker
Phytophthora spp. (P
Affects 45 plants
Boron Deficiency
Many commercial
Affects 19 plants
Botryosphaeria Dieback
Botryosphaeria dothidea
Affects 134 plants
Botrytis Blight
Botrytis cinerea
Affects 48 plants
Botrytis Bud and Twig Blight
Botrytis cinerea
Affects 19 plants
Botrytis Bunch Rot Gray Mold
Botrytis cinerea
Affects 4 plants
Botrytis Petal Blight
Botrytis cinerea
Affects 137 plants
Botrytis Shoot Blight
Botrytis cinerea
Affects 164 plants
Box Blight
Affects 6 plants
Boxwood Blight
Boxwood blight
Affects 4 plants
Branch Canker
Various fungi (Phoma spp., Phomopsis spp., Cytospora spp....
Affects 69 plants
Brand and Common Canker
Two fungi
Affects 8 plants
Brand canker
Affects 10 plants
Break Viruses
Multiple viruses: Little Cherry Virus-1 (LChV-1), Little ...
Affects 3 plants
Brittle Decay
Kretzschmaria deusta
Affects 45 plants
Broom Rust
Gymnosporangium libocedri
Affects 16 plants
Brown Canker
Cryptosporella umbrina (anamorph: Diaporthe umbrina)
Affects 8 plants
Brown Rot
Monilinia fructicola and M
Affects 37 plants
Brown Rot Blossom Blight and Fruit Rot
The fungi
Affects 38 plants
Bud Blight
Seifertia azaleae
Affects 132 plants
Bull's-eye Rot
Affects 12 plants
Bullhead
Non-pathogenic (physiological — cold damage during flower...
Affects 14 plants
Burrknot
Non-pathogenic (genetic/physiological)
Affects 14 plants
Cane Blight
Kalmusia coniothyrium
Affects 14 plants
Canker
Cytospora spp. (synonyms: Leucostoma, Valsa)
Affects 122 plants
Cedar Flagging
Evergreen plants
Affects 17 plants
Charcoal Rot
Macrophomina phaseolina
Affects 2 plants
Chemical Injury
Affects 22 plants
Cherry Mottle Leaf
The cherry
Affects 36 plants
Cherry Twisted Leaf
Cherry twisted
Affects 36 plants
Cold Injury
Affects 3 plants
Collar Rot
Phytophthora cactorum
Affects 37 plants
Common And Yellow Mosaics
Affects 3 plants
Common canker
Coniothyrium wernsdorffiae and Paraconiothyrium fuckelii
Affects 10 plants
Common Leaf Spot
Ramularia grevilleana
Affects 4 plants
Coniophora Growth
Fungal growth
Affects 3 plants
Cork Spot
Non-pathogenic (calcium deficiency)
Affects 4 plants
Crinkle Leaf and Deep Suture
Believed to
Affects 36 plants
Crown and Cane Gall
Agrobacterium tumefaciens
Affects 14 plants
Crown and Collar Rot
Phytophthora cactorum (primary), P
Affects 14 plants
Crown Gall
Rhizobium radiobacter (formerly Agrobacterium tumefaciens)
Affects 126 plants
Crown Rot
The fungal
Affects 3 plants
Crumbly Fruit
Raspberry bushy dwarf virus (RBDV) + raspberry leaf mottl...
Affects 14 plants
Cucumber mosaic virus
Affects 1 plant
Curly top (Beet curly top virus)
Affects 4 plants
Current-season Needle Necrosis
Affects 15 plants
Cutting Rots
Rhododendron and
Affects 141 plants
Cylindrocladium Blight and Root Rot
Cylindrocladium scoparium
Affects 135 plants
Cytospora Canker
Cytospora canker
Affects 137 plants
Damping-off
Several soilborne
Affects 66 plants
Dead Bud
Affects 33 plants
Dead Spur
Apple dead
Affects 12 plants
Decline
Pear decline
Affects 5 plants
Diplodia Canker
Several Diplodia spp. can cause branch cankers on apple b...
Affects 12 plants
Downy Mildew
Peronospora sparsa
Affects 40 plants
Drought Injury
Many conifers
Affects 37 plants
Dry Berry
Described as
Affects 14 plants
Dutch Elm Disease
Affects 8 plants
Dwarf Mistletoe
Arceuthobium spp. (parasitic plant)
Affects 64 plants
Eastern Filbert Blight
Affects 6 plants
Elytroderma Needle Cast
Affects 53 plants
Eola Rasp Leaf (Yellow Bud Mosaic)
Eola rasp
Affects 36 plants
European Canker Nectria Canker
Nectria cinnabarina (asexual: Tubercularia vulgaris) and ...
Affects 2 plants
Fabraea Leaf Spot
Affects 4 plants
Failure to bloom
Affects 5 plants
Fasciation
Multiple possible causes (see Disease Cycle section)
Affects 45 plants
Fire Blight
Erwinia amylovora
Affects 64 plants
Flat Apple Disease
Apple flat
Affects 12 plants
Flower and Petal Blight
Ciborinia camelliae
Affects 2 plants
Frosty Mildew
Microstroma album
Affects 50 plants
Fruit Rot
Phytophthora cactorum
Affects 29 plants
Fruit Rot and Cane Botrytis
Botrytis cinerea
Affects 14 plants
Fruit Rot, Phytophthora
Phytophthora cactorum
Affects 12 plants
Fruit Russeting
Fruit russet
Affects 18 plants
Fungal Cankers
Although bacterial
Affects 36 plants
Fungal leaf spots
Phyllosticta sp. and Dothiorella candollei (formerly Macr...
Affects 5 plants
Fusarium Root Rot
Fusarium spp.
Affects 3 plants
Fusicoccum Canker (Godronia Canker)
Godronia cassandrae
Affects 12 plants
Ganoderma Root and Butt Rot
Ganoderma applanatum
Affects 50 plants
Gray Blight
Pestalotiopsis sydowiana
Affects 132 plants
Gray Mold
Botrytis cinerea
Affects 79 plants
Green Algae
Green algae
Affects 15 plants
Green Crinkle Disease
This disease
Affects 12 plants
Grovesiella Canker
Affects 15 plants
Gumming
Mechanical injury
Affects 36 plants
Gumming (Gummosis)
Non-pathogenic (physiological response to injury/stress)
Affects 33 plants
Hail damage
Affects 5 plants
Herbicide damage
Affects 5 plants
Hypocotyl Rot and Root Rot
In most
Affects 42 plants
Incorrect soil pH
Non-pathogenic (abiotic — soil pH imbalance)
Affects 12 plants
Inonotus Root and Butt Rot
Pseudoinonotus dryadeus
Affects 50 plants
Interior Needle Blight
Multiple fungi (Rhizosphaera spp., Stigmina spp., Lirula ...
Affects 15 plants
June Drop
The normal
Affects 36 plants
Laminated Root Rot
Coniferiporia sulphurascens
Affects 9 plants
Latent Virus Diseases
Three viruses
Affects 12 plants
Leaf And Cane Spot
Affects 5 plants
Leaf and Flower Gall
Exobasidium vaccinii
Affects 135 plants
Leaf and Shoot Blight
Affects 11 plants
Leaf Blight
Affects 46 plants
Leaf Blight (Keithia Blight)
Didymascella thujina
Affects 3 plants
Leaf Blister
Taphrina spp.
Affects 109 plants
Leaf Burn
Non-pathogenic (abiotic stress)
Affects 132 plants
Leaf Curl
Affects 36 plants
Leaf Gall
Affects 40 plants
Leaf Rust
Affects 11 plants
Leaf Scorch
abiotic (drought, heat stress) or bacterial (Xylella fast...
Affects 325 plants
Leaf scorch (marginal leaf necrosis)
Sphaerulina azaleae (formerly Septoria azaleae)
Affects 7 plants
Leaf Scorch And Leaf Roll
Sphaerulina azaleae (formerly Septoria azaleae)
Affects 22 plants
Leaf Spot
Various fungi (Phyllosticta spp., Septoria spp., Cercospo...
Affects 545 plants
Leaf spot (Diplocarpon)
Diplocarpon spp.
Affects 6 plants
Leaf Spots and Blights
Phyllosticta sp. and Dothiorella candollei (formerly Macr...
Affects 2 plants
Leaf Spots, Miscellaneous
Several fungal
Affects 8 plants
Leafroll
Affects 38 plants
Leather Rot
The fungal
Affects 2 plants
Lilac Ring Mottle
Lilac ring
Affects 13 plants
Lime-induced Chlorosis
Non-pathogenic (iron deficiency)
Affects 143 plants
Little Cherry
Little cherry
Affects 33 plants
Lophodermella Needle Cast
Affects 53 plants
Lophodermium Needle Cast
Affects 53 plants
Lower Stem Canker
Affects 4 plants
Madrone Canker
Affects 1 plant
Magnesium Deficiency
Affects 20 plants
Marginal leaf necrosis
Affects 140 plants
Marssonina leaf and twig spot
Affects 14 plants
Marssonina Leaf Spot
Marssonina spp.
Affects 11 plants
Mistletoe
Arceuthobium spp. (parasitic plant)
Affects 56 plants
Mistletoe (a True Mistletoe)
Phoradendron villosum
Affects 70 plants
Moldy Core and Core Rots
Several different
Affects 12 plants
Mosses and Lichens
Affects 12 plants
Mottle leaf
Cherry mottle leaf virus
Affects 38 plants
Mummy Berry
Monilinia vaccinii-corymbosi
Affects 13 plants
Necrotic Leaf Blotch (Golden Leaf Drop)
Non-pathogenic (physiological)
Affects 12 plants
Necrotic Leaf Spot
Isolation attempts
Affects 12 plants
Necrotic Ringspot
A potexvirus, rhododendron necrotic ringspot virus, has b...
Affects 133 plants
Necrotic rusty mottle
Uncharacterized graft
Affects 38 plants
Necrotic Rusty Mottle (Lambert Mottle) and Rusty Mottle
Uncharacterized graft
Affects 36 plants
Nectria Canker
Neonectria ditissima
Affects 135 plants
Nectria Canker (European Canker)
Neonectria ditissima
Affects 18 plants
Nectria Twig Blight (Coral Spot)
Nectria cinnabarina
Affects 14 plants
Needle Blight
The fungi
Affects 16 plants
Needle Cast
Rhabdocline spp. including R
Affects 63 plants
Needle Cast, Rhabdocline
Rhabdocline spp
Affects 4 plants
Needle Cast, Swiss
Nothophaeocryptopus gaeumannii
Affects 4 plants
Nematode, Dagger
Xiphinema americanum
Affects 8 plants
Nematode, Foliar
Aphelenchoides fragariae
Affects 0 plants
Nematode, Ring
Mesocriconema spp
Affects 2 plants
Nematode, Root-knot
Meloidogyne hapla
Affects 3 plants
Nematode, Root-lesion
Pratylenchus penetrans
Affects 7 plants
Nematode, Stem and Bulb
Ditylenchus dipsaci
Affects 0 plants
Nematode, Stubby-root
Paratrichodorus renifer
Affects 7 plants
Nematode, Stunt
Tylenchorhynchus claytoni
Affects 0 plants
Nematodes
Nematodes are
Affects 7 plants
Oedema
Non-pathogenic (physiological — water imbalance)
Affects 5 plants
Oil Discoloration of Foliage
abiotic (spray oil residue)
Affects 15 plants
Orange Rust
Affects 14 plants
Orford-cedar (Chamaecyparis lawsoniana)
Affects 1 plant
Ovulinia Petal Blight
Ovulinia azaleae
Affects 135 plants
Pacific Coast Pear Rust
Gymnosporangium libocedri
Affects 4 plants
Pear Trellis Rust
Affects 23 plants
Pecky Rot
Postia amara
Affects 1 plant
Pencil Rot (Brown Pocket Rot)
Stem decay
Affects 3 plants
Perennial Canker (Bull's-eye Rot)
Cryptosporiopsis perennans
Affects 19 plants
Phomopsis Twig Blight
Diaporthe vaccinii
Affects 20 plants
Phyllosticta Leaf Spot
Phyllosticta spp.
Affects 45 plants
Physiological leaf spot
Non-pathogenic (physiological disorder)
Affects 138 plants
Physiological shothole
Affects 6 plants
Phytophthora Blight
Phytophthora spp.
Affects 133 plants
Phytophthora Blight and Dieback
Many different
Affects 132 plants
Phytophthora Canker
Phytophthora syringae
Affects 16 plants
Phytophthora Canker and Shoot Blight
Phytophthora spp. (P
Affects 13 plants
Phytophthora fruit rot
Phytophthora spp
Affects 14 plants
Phytophthora leaf & twig blight
Phytophthora spp.
Affects 0 plants
Phytophthora Leaf and Twig Blight
Phytophthora ilicis
Affects 10 plants
Phytophthora Root and Crown Rot
Phytophthora cinnamomi
Affects 4 plants
Phytophthora Root Rot
Phytophthora spp. (P
Affects 395 plants
Phytophthora Root Rot and Wilt
Affects 132 plants
Pitting
Affects 36 plants
Plum Pockets
Affects 36 plants
Pollination failure
Affects 1 plant
Postharvest Rots
Many fungi
Affects 36 plants
Powdery Mildew
Podosphaera aphanis var. aphanis
Affects 598 plants
Prune Dwarf
Prune dwarf
Affects 36 plants
Prunus Necrotic Ringspot
Prunus necrotic
Affects 38 plants
Pseudomonas Blight
A bacterium, Pseudomonas syringae pv. syringae
Affects 14 plants
Pseudomonas Blossom Blast and Dieback
Pseudomonas syringae
Affects 4 plants
Ramorum leaf and shoot blight (Sudden oak death)
Phytophthora ramorum
Affects 167 plants
Ramorum Leaf Blight
Affects 132 plants
Ramorum Leaf Blight and Shoot Dieback
Phytophthora ramorum"filthy five\" genera are inc
Affects 185 plants
Ramorum Shoot Dieback
Phytophthora ramorum
Affects 0 plants
Rasp Leaf
Cherry rasp
Affects 36 plants
Red Leaf Spotting
Several factors
Affects 15 plants
Red Stele
Phytophthora fragariae var. fragariae
Affects 3 plants
Replant Disease
Complex of Pythium spp., Phytophthora spp., Rhizoctonia s...
Affects 62 plants
Rhizosphaera Needle Cast
Affects 16 plants
Ringspot
Tomato ringspot
Affects 19 plants
Ringspot Disease
Affects 2 plants
Ripe Rot (Anthracnose)
Colletotrichum spp.
Affects 12 plants
Root Rot
Phytophthora rubi
Affects 200 plants
Root Rot (Armillaria)
Affects 1 plant
Root Rot, Phytophthora
Phytophthora spp.
Affects 15 plants
Rose Mosaic
Several viruses
Affects 8 plants
Rosette
This problem
Affects 36 plants
Rubbery Wood and Flat Limb
These diseases
Affects 12 plants
Rugose
Affects 36 plants
Russeting
Non-pathogenic (physiological disorder — epidermal cell d...
Affects 36 plants
Rust
Thekopsora minima and Naohidemyces vaccinii
Affects 400 plants
Salt injury
Affects 1 plant
Scab
Venturia inaequalis
Affects 66 plants
Scar Skin and Dapple Apple
These diseases
Affects 12 plants
Scorch
The blueberry
Affects 12 plants
Seiridium Canker
Affects 37 plants
Shock
The blueberry
Affects 12 plants
Shoot Tip Dieback
Multiple causes (Phomopsis spp., Kabatina spp., Pestaloti...
Affects 3 plants
Shothole
Affects 36 plants
Shothole (Coryneum Blight)
Affects 35 plants
Silver Leaf
Chondrostereum purpureum
Affects 59 plants
Slime Mold
Affects 2 plants
Sooty Bark Disease
Cryptostroma corticale
Affects 45 plants
Sooty Mold
Fumago vagans
Affects 23 plants
Sooty Mold (Black Mold)
Saprophytic fungi
Affects 2 plants
Sour Cherry Yellows
Prune dwarf
Affects 36 plants
Sprinkler Rot (Phytophthora Fruit Rot)
Phytophthora spp
Affects 40 plants
Spur Blight
Xenodidymella applanata
Affects 14 plants
Stamen Blight
Affects 14 plants
Stem Canker
Botryosphaeria corticis
Affects 50 plants
Stem Decay
Stem decay
Affects 61 plants
Stem Pitting
Several causes
Affects 36 plants
Stem Rot
Phytophthora syringae (primary), P
Affects 18 plants
Stigmina Blight
Pseudocercospora thujina
Affects 4 plants
Stony Pit
Graft-transmissible virus (causal virus not definitively ...
Affects 4 plants
Storage Problems
Affects 12 plants
Storage Rots
Affects 4 plants
Sudden Oak Death
Phytophthora ramorum
Affects 54 plants
Sunburn
Non-pathogenic (abiotic — solar radiation damage)
Affects 10 plants
Sycamore Anthracnose
Apiognomonia veneta (syn. Gnomonia platani)
Affects 4 plants
Tar Spots
Rhytisma punctatum
Affects 45 plants
Thousand Cankers Disease
Geosmithia morbida (vectored by Pityophthorus juglandis)
Affects 7 plants
Tissue Proliferation
Non-pathogenic; genetic/physiological abnormality from ti...
Affects 1 plant
Trellis Rust (European Pear Rust)
Gymnosporangium sabinae
Affects 4 plants
Twig Blight
Diaporthe vaccinii
Affects 87 plants
Twig blight (Venturia)
Venturia spp.
Affects 14 plants
Twig Canker
Sporocadus lichenicola
Affects 12 plants
Twig Dieback and Canker
Phacidiopycnis washingtonensis
Affects 12 plants
Union Necrosis and Decline
Tomato ringspot
Affects 12 plants
Upper and Lower Stem Canker (Phoma Blight)
Phoma spp.
Affects 4 plants
Variegation
Both a
Affects 2 plants
Vein Yellows (Red Mottle and Sooty Ringspot of Quince)
Vein yellows
Affects 4 plants
Verticillium Wilt
Verticillium dahliae
Affects 179 plants
Virus
Various plant viruses (Raspberry bushy dwarf virus, Straw...
Affects 100 plants
Virus and Virus-like Diseases
Affects 4 plants
Virus Diseases
Various plant viruses (Blueberry mosaic virus, Blueberry ...
Affects 95 plants
Virus-induced Cherry Decline
One of
Affects 36 plants
Volutella Leaf and Stem Blight (Canker)
Pseudonectria buxi
Affects 4 plants
Web Blight
Rhizoctonia spp. (binucleate)
Affects 5 plants
Western Gall Rust
Affects 53 plants
White mold
Affects 2 plants
White Mold Sclerotinia Rot
Affects 3 plants
White Pine Blister Rust
Cronartium ribicola
Affects 53 plants
White Pocket Rot (Piped Rot)
Inonotus dryophilus
Affects 50 plants
Winter Injury
Cold and
Affects 9 plants
Witches' Broom
Taphrina wiesneri
Affects 195 plants
Witches' Broom Rust
Affects 13 plants
Witches'-broom (Cherry leaf curl)
Taphrina wiesneri
Affects 38 plants
Wood Decay
Limb and
Affects 125 plants
X-Disease
Candidatus Phytoplasma pruni
Affects 36 plants
Yellow Root Rot
Perreniporia subacida
Affects 3 plants
Yellow Rust
Phragmidium rubi
Affects 14 plants
Yellow-green Mottle Syndrome
Affects 4 plants