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Rhododendron - Rhododendron ponticum

Terrestrial, the Rhododendron is prevalent throughout gardens and forested areas in Ireland.

Rhodedendron poses a threat to native ecosystems and species and negatively impacts the forestry industry. 

Rhododendron ponticum is prevalent throughout Ireland.

What does it look like?
It is readily recognised by its distinctive attractive pink flowers and large dark green oval shaped leaves. Rhododendron can grow quite tall with specimens regularly attaining 8 metres in height.

The plant invades three habitats, which are deemed internationally important under the Habitats Directive: upland oak woods, bogs, and heath. Rhododendron plants form impenetrable undergrowth that decreases daylight and reduces native plant cover. The plants also secrete toxins that reduce the regeneration of native plants. The tissues of Rhododendron contain high concentrations of phenols, which are highly toxic if ingested by herbivores, and it has few natural enemies. Rhododendron is also host to the plant fungus Phytophthora ramorum that can cause “Sudden Oak Death”, and is therefore a threat to oak forests.

Where is it originally from?
The species is native to Europe and Asia, specifically Spain and Turkey and was introduced to Ireland an ornamental garden plant.

What can you do?
Visit the Invasive Species Ireland website to find out more and to report sitings.

©2007 Department of the Environment, Heritage and Local Government