Russian Hawthorn
Crataegus ambigua
Rosaceae · broadleaf deciduous tree · introduced
Last updated
Plant Profile
Size & Form
Height
15–40 ft
Spread
15-25 ft
Growth Rate
Moderate
Site Requirements
Light
Full Sun
Soil Drainage
Adaptable
Soil pH
5.0-8.5 (moderately acidic to strongly alkaline)
Water
Low
Drought Tolerance
High
Hardiness
Zones 5a–8b
Ornamental Interest
Bloom Time
Spring
Fall Color
Yes
Origin
southern Russia ambigua: uncertain, doubtful (an apparent
Watch for this season
Fire BlightHigh
Bloom Infection Window
Powdery MildewHigh
Active Conidial Spread
RustHigh
Uredinial Stage (Summer)
Adult Flight
+ 3 more — see full disease and pest lists below
Diseases: Regionally Documented (6)
Venturia spp. — multiple host-specific species: V Scab Multiple genera (Melampsoridium, Thekopsora, Naohidemyces... Rust Symptom category — not a single disease Leaf Spot Erwinia amylovora Fire Blight Symptom category — not a single disease Canker Multiple obligate biotrophic fungi (Erysiphales: Erysipha... Powdery Mildew
Pests: Regionally Documented (10)
Tetranychidae Spider mite Coccoidea Scale insect Caliroa cerasi Pear slug Dysaphis crataegi Hawthorn aphid Choreutis pariana Apple-and-thorn skeletonizer Acanthococcus azaleae Azalea bark scale Enarmonia formosana Cherry bark tortrix Hyphantria cunea Fall webworm Tortricidae Leafroller Malacosoma spp. Tent caterpillar
Data Maturity Structured Multiple sources. Expert review underway.