Diseases
112 diseases tracked across Western Washington landscapes, with host plants, symptoms, and management.
Data collection is ongoing. Profiles deepen as symptoms, management strategies, GDD thresholds, and regional notes are verified from extension research.
Showing 112 diseases
Alternaria Fruit Rot
Alternaria spp
Affects 12 plants
Anthracnose (Shade Trees)
Discula destructiva (dogwood), Kabatiella and Discula spp...
Affects 175 plants
Anthracnose Blotch
Ophiognomonia leptostyla (syn. Gnomonia leptostyla)
Affects 5 plants
Armillaria Root Rot
Armillaria spp. — primarily A
Affects 462 plants
Ascospora Dieback
Seimatosporium lichenicola
Affects 14 plants
Aster Yellows
Candidatus Phytoplasma asteris
Affects 2 plants
Bacterial Blight
Pseudomonas syringae pv. syringae
Affects 93 plants
Bacterial Canker
Pseudomonas syringae pv. syringae
Affects 50 plants
Bigleaf Maple Decline (Bigleaf Maple Dieback)
Affects 45 plants
Black Canker (Target Canker)
Ceratocystis fimbriata (black canker); Cytospora notastro...
Affects 11 plants
Black Knot
Apiosporina morbosa
Affects 38 plants
Black Mold
Chlaropsis thielavioides
Affects 12 plants
Black Root Rot
Thielaviopsis basicola
Affects 42 plants
Black Spot
[NOTE: Diplocarpon rosae causes black spot on roses (Rosa...
Affects 11 plants
Bleeding Canker
Phytophthora spp. (P
Affects 45 plants
Boron Deficiency
Many commercial
Affects 19 plants
Botryosphaeria Dieback
Botryosphaeria dothidea
Affects 134 plants
Botrytis cinerea (Gray Mold)
Botrytis cinerea
Affects 0 plants
Boxwood Blight
Boxwood blight
Affects 4 plants
Branch Canker
Symptom category — not a single disease
Affects 24 plants
Break Viruses
Little Cherry Virus-1 and Little Cherry Virus-2
Affects 3 plants
Brown Canker
Cryptosporella umbrina (anamorph: Diaporthe umbrina)
Affects 8 plants
Brown Rot Blossom Blight and Fruit Rot
Monilinia fructicola and M
Affects 38 plants
Bud Blight
Seifertia azaleae
Affects 132 plants
Bull's-eye Rot
Neofabraea malicorticis (anamorph: Cryptosporiopsis curvi...
Affects 0 plants
Cane and Leaf Spot
Sphaerulina westendorpii (formerly Septoria rubi) on Rubu...
Affects 2 plants
Cane Blight
Kalmusia coniothyrium
Affects 15 plants
Canker
Symptom category — not a single disease
Affects 115 plants
Cercospora Leaf Spot
Cercospora hydrangeae Ellis & Everh
Affects 1 plant
Cherry Mottle Leaf
Cherry mottle leaf virus
Affects 4 plants
Common Leaf Spot
Ramularia grevilleana
Affects 4 plants
Crown and Collar Rot
Phytophthora cactorum (primary), P
Affects 13 plants
Crown Gall
Rhizobium radiobacter (formerly Agrobacterium tumefaciens)
Affects 125 plants
Cylindrocladium Blight and Root Rot
Cylindrocladium scoparium
Affects 135 plants
Cytospora Canker
Cytospora spp. (Valsa spp., Leucostoma spp.)
Affects 137 plants
Damping-off
Several soilborne
Affects 66 plants
Decline/Collapse Syndrome
Candidatus Phytoplasma pyri
Affects 6 plants
Diplodia Canker
Diplodia seriata and D
Affects 12 plants
Downy Leaf Spot
Pseudomicrostroma juglandis (syn. Microstroma juglandis)
Affects 6 plants
Downy Mildew
Multiple obligate oomycetes (Peronosporaceae); species ar...
Affects 43 plants
Drippy Dieback
Lonsdalea quercina subsp
Affects 13 plants
Dry Cell (Dry Berry) Syndrome
Monilinia rubi
Affects 14 plants
Early Leaf Spot
Phyllosticta cotoneastri (primary); Entomosporium maculat...
Affects 13 plants
Fabraea Leaf Spot
Fabraea maculata
Affects 4 plants
Fire Blight
Erwinia amylovora
Affects 68 plants
Flower and Petal Blight
Ciborinia camelliae
Affects 2 plants
Fusarium Wilt
Fusarium oxysporum
Affects 6 plants
Fusicoccum Canker (Godronia Canker)
Godronia cassandrae
Affects 12 plants
Grapevine Trunk Disease
Eutypa lata, Botryosphaeria spp., Phaeomoniella chlamydos...
Affects 2 plants
Gray Blight
Pestalotiopsis sydowiana
Affects 132 plants
Heterobasidion Root Disease
Heterobasidion annosum
Affects 78 plants
Laminated Root Rot
Coniferiporia sulphurascens
Affects 9 plants
Leaf and Flower Gall
Exobasidium vaccinii
Affects 135 plants
Leaf Blight (Keithia Blight)
Didymascella thujina
Affects 3 plants
Leaf Blister
Taphrina spp.
Affects 109 plants
Leaf Curl
Taphrina deformans
Affects 36 plants
Leaf Scorch And Leaf Roll
Sphaerulina azaleae (formerly Septoria azaleae)
Affects 0 plants
Leaf Spot
Symptom category — not a single disease
Affects 533 plants
Leafroll
Grapevine leafroll virus
Affects 38 plants
Little Cherry
Little cherry virus-1 and Little cherry virus-2
Affects 33 plants
Mistletoe (a True Mistletoe)
Phoradendron villosum
Affects 70 plants
Mummy Berry
Monilinia vaccinii-corymbosi
Affects 13 plants
Necrotic Ringspot
Rhododendron necrotic ringspot virus
Affects 133 plants
Nectria Canker
Neonectria ditissima
Affects 135 plants
Ovulinia Petal Blight
Ovulinia azaleae
Affects 135 plants
Pear Scab
Venturia pirina
Affects 0 plants
Phytophthora Canker
Phytophthora syringae
Affects 15 plants
Phytophthora Leaf and Twig Blight
Phytophthora ilicis
Affects 2 plants
Phytophthora ramorum (Ramorum Blight / Sudden Oak Death)
Phytophthora ramorum
Affects 0 plants
Phytophthora Root Rot
Phytophthora spp. (P
Affects 256 plants
Powdery Mildew
Multiple obligate biotrophic fungi (Erysiphales: Erysipha...
Affects 601 plants
Prunus Necrotic Ringspot
Prunus necrotic ringspot virus (PNRSV)
Affects 38 plants
Red Leaf Spot
Phyllosticta cotoneastri
Affects 13 plants
Replant Disease
Pythium spp., Phytophthora spp., Rhizoctonia spp., Fusari...
Affects 62 plants
Ripe Rot (Anthracnose)
Colletotrichum spp.
Affects 12 plants
Root Rot
Symptom category — not a single disease
Affects 182 plants
Rust
Thekopsora minima and Naohidemyces vaccinii
Affects 400 plants
Scab
Venturia spp. — multiple host-specific species: V
Affects 66 plants
Sclerotinia White Mold
Sclerotinia sclerotiorum
Affects 0 plants
Scorch
Blueberry scorch virus (BlScV)
Affects 12 plants
Seiridium Canker
Seiridium cardinale
Affects 37 plants
Shock
Blueberry shock virus (BlShV)
Affects 12 plants
Shothole
Stigmina carpophila or Diaporthe spp.
Affects 36 plants
Silver Leaf
Chondrostereum purpureum
Affects 59 plants
Slime Mold
Physarum spp. or similar myxomycetes
Affects 2 plants
Sooty Mold
Fumago vagans
Affects 23 plants
Sooty Mold (Black Mold)
Saprophytic fungi
Affects 2 plants
Sour Rot
Geotrichum candidum
Affects 2 plants
Spur Blight
Xenodidymella applanata
Affects 15 plants
Stamen Blight
Anthophora dendrobii or Botryotinia fuckeliana
Affects 14 plants
Stem Canker
Botryosphaeria corticis
Affects 50 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
Sycamore Anthracnose
Apiognomonia veneta (syn. Gnomonia platani)
Affects 2 plants
Tar Spots
Rhytisma punctatum
Affects 45 plants
Twig Blight
Multiple fungal species cause twig blight on different ho...
Affects 67 plants
Twig Blight (Scab)
Venturia spp. or Fusicladium spp. (specific oak pathogen ...
Affects 11 plants
Twig Canker
Sporocadus lichenicola
Affects 12 plants
Upper and Lower Stem Canker (Phoma Blight)
Phoma eupyrena
Affects 4 plants
Verticillium Wilt
Verticillium dahliae
Affects 180 plants
Virus
Raspberry bushy dwarf virus and related viruses
Affects 99 plants
Virus Diseases
Blueberry mosaic virus and related viruses
Affects 94 plants
Virus-induced Cherry Decline
Cherry leafroll virus (CLRV); complex with prune dwarf vi...
Affects 36 plants
Volutella Leaf and Stem Blight (Canker)
Pseudonectria buxi
Affects 4 plants
Walnut Blight
Xanthomonas arboricola pv. juglandis
Affects 5 plants
Web Blight
Rhizoctonia spp. (binucleate)
Affects 5 plants
Witches' Broom
Taphrina wiesneri
Affects 163 plants
X-Disease
Candidatus Phytoplasma pruni
Affects 37 plants
Yellow Root Rot
Perreniporia subacida
Affects 3 plants
Yellow Rust
Phragmidium rubi-idaei
Affects 14 plants
Young Vine Decline
Phaeomoniella chlamydospora, Phaeoacremonium spp. (P
Affects 2 plants