Control Of Himalayan Balsam On The River Sid

Sidbashers Volunteer Group

Himalayan Balsam (Impatiens glandulifera) was brought to Britain by Victorian plant hunters (or possibly earlier) and propagated as a garden plant as part of the desire to create Asian/Oriental style gardens. Subsequently seeds escaped into other areas particularly near water courses where they not only thrive in the damp conditions but spread easily through water run-off.

Over many years the plant has infested various parts along the River Sid from its source near the Hare & Hounds down to the mouth of the river as well as its tributaries such as the Snod and the Roncombe. Left unchallenged it spreads at an alarming rate through seed dispersion from August onwards (seed heads ‘pop’ and can spread several meters around each plant) until, as an annual plant, the winter weather prevents any further activity. Any seeds entering the river are transported downstream, particularly when the river is in flood, thus creating new growths the following year. Over time the river banks become infested and as the plant outcompetes the native species a mono-culture is created which gradually spreads from the river banks to adjoining land.

Landowner Responsibilities

Himalayan Balsam is designated an ‘Invasive Species’ in the Wildlife and Countryside Act 1981 and it is landowners’ responsibility to prevent its spread from their own land, including residential gardens. However, few landowners have met this obligation resulting in the situation we have across many of the rivers in our area and other parts of the country.

Activities of the Sidbashers

The Sid Bashers group was formed approximately 10 years ago by Peter Endersby and Lynnette Talbot as a Sidmouth in Bloom initiative and over those years has had numerous volunteers working along many areas of the Sid. However, the extent of the problem, the terrain involved and the falling number of volunteers has been such that eradication has been impossible. For the last few years the group has been working to contain the problem downstream from Sidbury/Sidford as far as Fortescue Farm and a reasonable level of success has been achieved. This initiative has limited the spread further downstream into areas such as Gilchrist Field, Margaret’s Meadow and beyond.

The group starts each season as soon as the plants are presenting themselves above other vegetation (usually mid to late May) working one morning each week until the seeds start to ‘pop’ in late August. Volunteers meet every Tuesday at 9.30am and finish around 1.00pm at locations determined by the greatest need.

Based on experience so far gained it is likely that the need for this work will be ongoing each season for the foreseeable future. The activity is challenging but highly rewarding and with more volunteers it would be possible not only to clear more rapidly and thoroughly the areas concentrated on so far but would enable clearance of areas further upstream. This level of control would lead to a significant reduction in re-infestation in the lower areas the following year.

This work is vital to keep indigenous species thriving along our rivers and adjoining land as well as to prevent balsam spreading even further afield which has already started along the verges of our roads. Should you have a few hours available each week from May until August and/or require any further information on the subject would you please contact Roger Woolley via email on: roger.carolwoolley@talktalk.net