Spotlight on... Himalayan Balsam

Indian Balsam (Impatiens glandulifera) © Rod Trevaskus

What is Himalayan Balsam?

Himalayan, or Indian, Balsam (Impatiens glandulifera) is one of the most severe invasive species in the UK. Originating from the Himalayas, where it shows none of the same damaging effects, it was introduced in the 19th century as an ornamental plant, and it does have beautiful purple/pink flowers. However it quickly spread throughout the UK during the two world wars due to the lack of mechanical management of the waterways, and the shortage of labour.

It primarily inhabits the riparian zone, the habitat adjacent to a waterway, and will grow in dense strands containing almost exclusively balsam. It emerges early and has the highest rate of growth of any plant in the herb layer, and rapidly grows up to 3m in height, allowing it to outcompete other species for light. The explosive seed dispersal which gives the plant its name, Impatiens meaning impatient, glandulifera meaning bearer of glands, allows the plant to expel its seeds up to 6m away, often into the nearby water source, where it will spread downstream.  

It is difficult to control, due to its efficient dispersal and ability to maintain a seedbank for up to 2 years,  but pulling up all individuals and snapping the stem just above the roots is a cheap and effective way to control individual populations, and “balsam bashing” events are frequently put on by various conservation organisations. However to control the spread across the country, detailed distribution data is required, and we need your help to gather this data. 

Where is Himalayan Balsam?

According to our database, Balsam is found throughout Oxfordshire and Berkshire, mainly along watercourses. However, our database only includes information which people have provided to us (and we have collected), so a lack of records doesn’t mean that Balsam isn’t present in the area. All it means is that no-one has told TVERC they’ve spotted them… yet!

Have you seen any Balsam?

If you spot any wildlife when you’re out and about, share your records and photos with TVERC. By letting TVERC know what you have seen you will help protect and improve your local environment by increasing the quality and quantity of data we hold. Photographs are always helpful too, as we keep an image gallery of species found in Oxfordshire and Berkshire.

Absence records are also very useful, so also let us know if you’ve been out and haven’t seen anything!

Your records can inform a variety of exciting biodiversity projects and help people make informed decisions about how to develop and manage land sustainably. We are a ‘not for profit’ organisation so rely on valuable help from skilled volunteers to improve our database.

Identification help

Balsam is pretty easy to spot, and the excellent guide by the GB Non Native Species Secretariat shown below should allow for easy identification!

There is a useful app that is free to download called “PlantNet”. PlantNet allows you to take a picture of the plant and it will attempt to identify it for you. This is not 100% accurate, so you should always double check with other ID guides, but it’s often a good place to start in the identification of a difficult plant, and compare other app users’ images of that species with your own specimen.

Find out more

Check out the links below for more information on Balsam and how to identify it!

http://www.nonnativespecies.org/downloadDocument.cfm?id=33

https://www.rhs.org.uk/advice/profile?pid=480

Where should we direct our spotlight next?

If you are a recorder, a local recording group or just have an interest in a species, send us your suggestion for a species, along with some facts and a photo (if possible) to tverc@oxfordshire.gov.uk.