Kirsty Brown – Conservation Project Assistant
Himalayan Balsam (Impatiens glandulifera) in the UK can be a contentious plant – some people like it and some people loathe it. From a water quality point of view, it’s bad news.
Now in the winter months the detrimental effects of the species are obvious on bare unvegetated river banks where the invasive plant has died back and where it suppressed other vegetation during the summer which could have stabalised the bank, and so the soil from the banks crumbles and slips into the water and chokes the river habitat.
A targeted top-down approach is being taken which started with the River Seph in the north, with the objective of eliminating Himalayan balsam from the uppermost reaches of the catchment by repeat control over and over again, and expanding slowly downstream and onto the River Rye. It’s this targeted concerted effort that can make a difference as it is the abundant seed released each year and carried downstream that means the balsam is so prolific and recalcitrant.
Over the last seven years contractors, land managers, volunteers and apprentice teams have been tackling the plant. Hand-pulling and strimming have been the only methods of control used, due to the proximity to the watercourse. Permission from the land owners and land managers along the banks has been vital, and the local Bilsdale Beacon newsletter has been used regularly to keep the wider local community informed.
The work is proving effective – in 2014 only a few Himalayan balsam plants were found along the River Seph and were easily hand pulled by our apprentices, at the same time the banks are becoming revegetated with native meadowsweet and willowherb. This is very encouraging and makes the aim of the project to eradicate Himalayan balsam from the Seph catchment and the stretch of the Rye catchment that lies within the National Park, seem actually possible. The efforts over the past seven years have made great inroads into achieving this aim, but there is still work to do.