12.5.2008 - HIMALAYAN BALSAM – A BEAUTIFUL BUT DEADLY ENEMY TO BRITISH COUNTYSIDE.

Article by Sue Wardle.

As a resident of the beautiful Consall valley, which runs into the Churnet valley, I am writing to draw people’s attention to the existence of this extremely invasive plant which is threatening our local environment. I first saw Himalayan Balsam 20 years ago in the Cotswolds in the garden of a B&B. The owners did not know the name of this very pretty orchid-like flower. Thank heavens, I did not take a cutting. Since then, this pernicious weed has invaded every county in the UK either in gardens or in the countryside, usually both. You can see it by the roadside, by railway lines, by canals, rivers and in some areas it completely swamps fields. “What’s wrong with that?” I hear you say,” it’s very pretty!”  Well yes, but it also forms a monoculture, it grows so thickly and strongly that nothing else survives around it or underneath it, thus swamping our native vegetation.

HOWEVER, the answer is actually very simple. It reproduces by producing seeds which germinate very easily. The plant is an annual so only survives by seeding. So PULL IT OUT!! Before it seeds. It comes up very easily root and all, then needs breaking below the first leaf node. This will stop it from producing seed and no seed = no plant.  If every one would pull out this invader whenever they see it, the problem could be managed quite simply. In Consall a group of environmentally friendly folk have got together and they are determined to rid their beautiful valley of this plant. It will be hard work initially. Can you help? Gloves, secaters and some garden waste sacks are all you need. If we are not vigilant, Consall and many other areas will be completely overrun by this monster.

Look at these photos and keep them in your mind. Then pull out this plant wherever you see it. If we all do it we will defeat it!

Himalayan balsam - some factual information

Himalayan or Indian Balsam (Impatiens glandulifera) was introduced to Britain in 1839, but escaped from gardens and rapidly colonised riverbanks and areas of damp ground.  Himalayan balsam grows in dense stands that suppress the growth of native grasses and other flora.  In the autumn, the plants die back, leaving the banks bare of vegetation and vulnerable to erosion.

Facts and figures

Native range: Western Himalayas

Stem: Pinky-red colour, up to 3m tall - tallest annual plant in Britain, hollow and jointed, sappy and brittle.

Leaves: Spear-shaped with serrated edges, shiny and dark green with a dark red midrib up to 150mm long opposite or in whorls of three.

Flowers: Purplish-pink to pale pink, slipper-shaped, on long stalks, June – October

Seeds : White, brown or black, produced from July – October, 4-7mm diameter, 4 – 16 seeds per pod.

Control: Control measures should aim to prevent flowering and if this is achieved before seeds are set, eradication is possible in two to three years.

Chemical control: Can use glyphosate or 2,4-D amine. Need to be used whilst plant is actively growing in early spring for best effect.

Cutting/mowing/strimming: Cut at ground level using a scythe, before the flowering stage in June.  Do not cut earlier as this promotes greater seed production in any plants that re-grow.  Cutting should be repeated annually until no more growth occurs.

Pulling: Shallow-rooted plants can be pulled up very easily and disposed of by burning or composting, unless seeds are present.

Grazing: Grazing by cattle and sheep is effective from April throughout the growing season. It should be continued until no new growth occurs.

 Useful link: http://www.arkive.org/species/ARK/plants_and_algae/Impatiens_glandulifera/