Troubleshooting
Narrow-Leaved Ash problems — and how to fix them
Narrow-Leaved Ash (Fraxinus angustifolia) is generally forgiving once you match its basics, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Emerald Ash Borer (EAB) risk
While EAB primarily affects North American ashes so far, F. angustifolia is considered highly vulnerable should EAB establish in its native range. Monitor closely in areas where EAB has been detected in Europe (it has spread into Russia and parts of central Europe).
Ash dieback (Hymenoscyphus fraxineus)
F. angustifolia is susceptible to ash dieback. Infected trees show wilting shoot tips, dark brown longitudinal streaks in sapwood, and crown dieback. Some research suggests slightly more field tolerance than F. excelsior, but the disease is still a serious threat.
Iron/manganese chlorosis
On highly alkaline or calcareous soils, interveinal chlorosis (yellowing between leaf veins) can develop due to iron or manganese lock-up. Address with chelated iron foliar feeds or soil acidification. Choose acid-tolerant rootstocks when grafting cultivars.
Prevent narrow-leaved ash problems before they start
Most narrow-leaved ash issues are care-mismatch, not bad luck. Dial in the basics:
Narrow-Leaved Ash problems — FAQ
Why is my narrow-leaved ash emerald ash borer (eab) risk?
While EAB primarily affects North American ashes so far, F. angustifolia is considered highly vulnerable should EAB establish in its native range. Monitor closely in areas where EAB has been detected in Europe (it has spread into Russia and parts of central Europe).
Why is my narrow-leaved ash ash dieback (hymenoscyphus fraxineus)?
F. angustifolia is susceptible to ash dieback. Infected trees show wilting shoot tips, dark brown longitudinal streaks in sapwood, and crown dieback. Some research suggests slightly more field tolerance than F. excelsior, but the disease is still a serious threat.
Why is my narrow-leaved ash iron/manganese chlorosis?
On highly alkaline or calcareous soils, interveinal chlorosis (yellowing between leaf veins) can develop due to iron or manganese lock-up. Address with chelated iron foliar feeds or soil acidification. Choose acid-tolerant rootstocks when grafting cultivars.