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Northern Japanese Hemlock

Tsuga diversifolia

Pinaceae · coniferous tree · introduced

Last updated March 8, 2026

Data Coverage 2 of 6 dimensions
Site Data
Threats
Cultivars
Phenology
GDD Thresholds
Puget Sound

Quick Facts

Height
80 ft
Light
Full Sun to Shade
Hardiness
Zone Zones 4–5
Bloom Time
Non-flowering
Origin
Japan

Diseases (12)

Phytophthora spp. (P Phytophthora Root Rot Heterobasidion annosum (syn. Fomes annosus) Annosus Root Rot Armillaria ostoyae Armillaria Root Rot Many conifers Drought Injury Arceuthobium spp. (parasitic plant) Dwarf Mistletoe Botrytis cinerea Gray Mold Heterobasidion annosum Heterobasidion Root Disease Coniferiporia sulphurascens Laminated Root Rot Thekopsora minima and Naohidemyces vaccinii Rust Phytophthora cactorum"heeled in\" (placed in sawdust pile... Shoot Blight Rhizoctonia spp. (binucleate) Web Blight Limb and Wood Decay

Pests (7)

Hemiberlesia ithacae Hemlock scale Adelges tsugae Hemlock woolly adelgid Dioryctria spp. Coneworm Coneworm and shoot moth Chionaspis pinifoliae Pine needle scale Otiorhynchus spp. Root weevil Hemlock adelgid

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