Troubleshooting
Incense Cedar problems — and how to fix them
Incense Cedar (Calocedrus decurrens) 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.
Cedar-apple rust / annosus root rot
Annosus root rot (Heterobasidion annosum) can affect mature trees, causing basal decay and eventual windthrow. Remove infected stumps promptly and treat freshly cut stumps with borax in areas where the disease is present.
Flatheaded borer (Agrilus)
Agrilus beetles attack stressed or drought-weakened trees, tunnelling under bark and girdling branches. Maintain tree vigour through adequate watering and avoid physical damage to the bark.
Needle blight (Pestalotiopsis / Kabatina)
Brownish needle tips and twig dieback during wet seasons. Prune affected shoots, improve air circulation, and apply preventive copper or chlorothalonil fungicide in humid climates.
Prevent incense cedar problems before they start
Most incense cedar issues are care-mismatch, not bad luck. Dial in the basics:
Looking for incense cedar in general rather than its problems? Read the full incense cedar care guide — light, water, soil and feeding.
Incense Cedar problems — FAQ
Why is my incense cedar cedar-apple rust / annosus root rot?
Annosus root rot (Heterobasidion annosum) can affect mature trees, causing basal decay and eventual windthrow. Remove infected stumps promptly and treat freshly cut stumps with borax in areas where the disease is present.
Why is my incense cedar flatheaded borer (agrilus)?
Agrilus beetles attack stressed or drought-weakened trees, tunnelling under bark and girdling branches. Maintain tree vigour through adequate watering and avoid physical damage to the bark.
Why is my incense cedar needle blight (pestalotiopsis / kabatina)?
Brownish needle tips and twig dieback during wet seasons. Prune affected shoots, improve air circulation, and apply preventive copper or chlorothalonil fungicide in humid climates.