Introduction

First introduced as an ornamental plant, Rhododendron Ponticum, by using its abundant seed production, has become invasive species. Rhododendron thrives in temperate and wet climatic conditions and prefers acidic soils with poor nutrients levels.

Description

It can grow as a shrub or a tree to a height of up to 10 metres at maturity.

It has dark-green waxy leaves of 6cm to 12 cm and pink to mauve flowers of up to 6 cm diameter.

Even if it may look attractive, Rhododendron has the ability to seed in abundance – a large plant may produce about a million of wind-dispersed seeds per year. Some bacteria help it to absorb nutrients from infertile soils which make it stronger and enable it to implant more rapidly

Impacts

Rhododendron Ponticum causes many ecological problems. Indeed, with a height of over 10 m and a covering upwards of up to 100 m² of ground for just an individual plant, it becomes considerably difficult for the natural flora to grow and Rhododendron quickly out-competes most native plants.

Rhododendron Ponticum deprives its local ecosystem of herbivorous invertebrates and the animals which feed on them to thrive in their own environment.

On riversides, even the water seems lifeless as there is no light for aquatic plants and consequently, little food for fish.

Even when Rhododendron is cleared from an area, rhododendron-derived materials, through allelopathy, remain which make it impossible for other species to grow.

Rhododendron is also a host for diseases of coniferous and hardwood trees.

It is also of note, even if it is very rare, that the nectar of this plant can cause poisoning to people.

Control Methods

To remove Rhododendron, mechanical diggers and chain-saws can be used nevertheless such techniques are not often practical and can accelerate re-growth.

The recommended method eliminating Rhododendron is a stem injection with Glyphosate.

 

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