Thomson Rhododendron

Rhododendron thomsonii subsp. thomsonii

Ericaceae · broadleaf · introduced

Quick Facts

Height

5 ft

Origin

the Himalaya --- Nepal, India (Sikkim

Diseases (28)

Root Rot (Phytophthora spp.)

Podosphaera aphanis var. aphanis Powdery Mildew

Ovulinia azaleae Ovulinia Petal Blight

Non-pathogenic (iron deficiency) Lime-induced Chlorosis

Various fungi (Phyllosticta spp., Septoria spp., Cercospo... Leaf Spot

Exobasidium vaccinii Leaf and Flower Gall

Cylindrocladium scoparium Cylindrocladium Blight and Root Rot

Botrytis cinerea Botrytis Petal Blight

Marginal leaf necrosis

Rhododendron and Cutting Rots

Non-pathogenic (abiotic stress) Leaf Burn

abiotic (drought, heat stress) or bacterial (Xylella fast... Leaf Scorch

Phytophthora Root Rot and Wilt

Ramorum Leaf Blight

Botryosphaeria dothidea Botryosphaeria Dieback

Seifertia azaleae Bud Blight

A potexvirus, rhododendron necrotic ringspot virus, has b... Necrotic Ringspot

Many different Phytophthora Blight and Dieback

Phytophthora ramorum"filthy five\" genera are inc Ramorum Leaf Blight and Shoot Dieback

Thekopsora minima and Naohidemyces vaccinii Rust

Taphrina wiesneri Witches' Broom

Armillaria ostoyae Armillaria Root Rot

Botrytis cinerea Botrytis Shoot Blight

Pestalotiopsis sydowiana Gray Blight

Non-pathogenic (physiological disorder) Physiological leaf spot

Phytophthora spp. Phytophthora Blight

Phytophthora spp. (P Phytophthora Root Rot

Phytophthora ramorum Ramorum leaf and shoot blight (Sudden oak death)