Himalayan Balsam Pulling Trial

Himalayan balsam pink flower

In summer you may often come across the pink ‘policemen’s helmet’ shaped flowers of Himalayan balsam (Impatiens glandulifera) on Exmoor. Native to Western and Central Himalaya, Himalayan balsam  was first introduced into the wild in 1855 and has become widespread mainly along riverbanks and in damp woodlands.

Its explosive seed dispersal, ejecting as many as 800 seeds up to seven metres from the parent plant, means that it can travel with ease both up and downstream. It grows very quickly and can reach heights of up to three metres crowding and shading out our native species. It produces high levels of nectar which means pollinators love it; however, this possibly attracts them away from our native plant species. Once dominant the shallow root system can promote erosion of riverbanks leading to increased flooding. It can also block out huge stretches of our riverbanks making areas inaccessible.

The Trial

Since 2014, we have been working with a dedicated team of volunteers to clear Himalayan balsam in our trial area on the River Barle, between Withypool and Tarr Steps.

Himalayan balsam has very shallow roots which means it can easily be pulled by hand. Once pulled the plant can be left on site, away from the river bank to decompose.  This should occur before the plants set seed and often requires several visits in one season to have the greatest impact. Like many invasive species in the UK, there is no quick solution, and control can take several years.

Himalayan balsam flower

Although we are currently unable to help with the control of Himalayan balsam elsewhere within the National Park we would be very interested to hear from you if you have Himalayan balsam on your property or have seen any while exploring the National Park.

We need your help!

We are working closely with volunteers and local communities to survey and map invasive species within the National Park which will help guide our work controlling them in the future. Please visit our Get Involved page if you would like to report an invasive species you have seen while exploring the National Park or you are interested in volunteering with us.

We can also give advice, so if you have an invasive species on your land that you are looking to control please do not hesitate to get in touch by email or phone.