The rhododendron blocks light, preventing other species from growing beneath it and leaving only trees that are able to grow above the level of the rhododendron canopy. Rhododendrons are an invasive plant that can grow indefinitely if not pruned seasonally (the largest Rhododendron on record currently stands at 108 ft [32.9 m] and is still growing!). Ethel Dutky, University of Maryland, Bugwood.org. There are over 900 species of Rhododendron, but only Rhododendron ponticum is invasive in Ireland. Because it is so expensive to control and physically prevents access, land has been abandoned. There are two subspecies of Rhododendron ponticum, subsp. At Kustom Landscapes & Ecology, we specialise in Rhododendron Ponticum control and removal in Dorset, Hampshire, Wiltshire, Bristol & Bath, Gloucestershire, Somerset and Devon, along with a range of other invasive plants. Rhododendron ponticum, native to southern Europe and south west Asia was introduced into the UK in the 18th Century. In its native habit, it grows as an understory plant in mixed forest or as a dwarfed form above the snowline. Allow room for plant to fill out. Notes on Taxonomy and Nomenclature Top of page The genus Rhododendron is the largest in the Ericaceae family with 1200 species. Specifically the hybrid Rhododendron x superponticum, a non-native species that has become invasive in the British countryside.. Popular for its rapid growth and abundant purple flowers, this rhododendron was bred in Victorian times and very widely planted in gardens, estates and country parks. Analogously, 3) it is assumed that growth rates of the invasive Rhododendron reach higher values than plants from the native origins. It has become what we class as a weed; an invasive species in the case of this particular rhododendron. Avoid close to trees, roots, invasive weeds, walls, hot patios, dry banks and waterlogged soils. In 2007 the area of Rhododendron ponticum within the National Park was estimated to be almost 4000ha (2% of the Park), we would expect this figure to be significantly higher today. There are around 1200 species of rhododendron. Rhododendron ponticum is thought of as a Stage V invasive species using the Colautti and Ma c Is a ac f ra m e wo rk . Use the height shown in 10 years as a guide to the distance between each plant. Rhododendron was first introduced in 1763 from the Iberian Peninsula for use in gardens, and there are now few areas of Great Britain that are not affected by this invasive plant. It is highly invasive. The organic material separates the clay molecules, creating fissures that roots and water can penetrate. More on impacts: Rhododendron forms monospecific stands with a dense and permanent canopy preventing the development of native species; it has the potential to prevent natural regeneration of native trees and to outcompete many species in wood- and heathlands.Competition is favoured by the production of allelopathic compounds. Rhododendron ponticum is an erect, evergreen Ericaceae shrub that reaches a height of 2–8 m (Tutin et al. Outside the garden, Rhododendron is a … It is a much greater […] An invasive species is a plant which is listed in the Wildlife and Countryside Act 1981. . rhododendron, once almost eradicated from killarney national park’s finest oak woods, has returned. The 30 years war: the fight against rhododendron It could swallow Ireland’s ancient woodlands, but experts disagree on how to combat it Sat, Aug 15, 2015, 05:18 The origins of rhododendron. Dozens of men’s sheds members from across the island are descending upon Killarney National Park to tackle the scourge of invasive rhododendron. Many of the bushes planted in Victorian times are still with us. Rhododendron ponticum, the common purple flowered rhododendron, thrives in the damp climate and acid soils of Snowdonia. Its native range is across Turkey, Lebanon, Bulgaria, the Caucasus, Spain and Portugal. By not allowing plants to escape from gardens and disposing of unwanted plants and weeds carefully, gardeners can help reduce the spread of invasive non-native species. Ericaceae roughly translates as heather or heath family. Peterson. This map shows where the Rhododendron ponticum appears in Ffestiniog area in purple (2011) I hate to see beautiful, mature shrubs destroyed, so I gladly took on this project. If planting closer for instant impact, be prepared to move plants after a few years. 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