It was introduced to Kew Gardens in 1839 and is thought to have mainly been spread by people passing seeds to each other.
They are highly invasive not just because they are fast growing but each plant can produce up to 800 seeds. These are dispersed widely as the ripe seedpods shoot their seeds up to 7m (22ft) away. They often grow along the edges of streams and rivers and therefore their seeds can travel even further due to the flow of the watercourse. Because of this they can easily out compete our native plants.
The species dies back over winter leaving bare river banks causing them to become susceptible to erosion.
It has been found mainly in the upper and middle catchment of the River Thame around Thame and Aylesbury. The main method of control is to pull out the plants from the root before they have a chance to seed. Due to their short roots they are relatively easy to pull out. If you would like to get involved in our annual Balsam Bashing events then please let us know.