Japanese Alder
Alnus japonica
Betulaceae · broadleaf deciduous tree · introduced
Last updated
Quick Facts
Height
80 ft
Spread
8-12 ft
Growth Rate
Fast
Light
Full Sun to Part Shade
Soil
Wet Tolerant
Water
High
Hardiness
Zone Zones 5a–8b
Bloom Time
March
Origin
far eastern Russia, China (Anhui
Watch for this season
Nectria CankerHigh
Spore Release (Fall & Spring Rains)
RustHigh
Aecial Stage (Alternate Host)
Tent caterpillarHigh
Larval Feeding
Armillaria Root RotModerate
Active Below-ground Growth
+ 4 more — see full disease and pest lists below
Diseases: Regionally Documented (11)
Armillaria spp. — primarily A Armillaria Root Rot Brown Leaf Blotch [VERIFY] Canker and Stem Diseases Viral agents Catkin Hypertrophy and Leaf Curl Collar Rot Lonsdalea quercina subsp Drippy Dieback Symptom category — not a single disease Leaf Spot Neonectria ditissima Nectria Canker Phytophthora spp. (P Phytophthora Root Rot Multiple obligate biotrophic fungi (Erysiphales: Erysipha... Powdery Mildew Multiple genera (Melampsoridium, Thekopsora, Naohidemyces... Rust
Pests: Regionally Documented (7)
Data Maturity Structured Multiple sources. Expert review underway.