Invasive Species Ireland is supporting Himalayan Balsam Bash 2012. This is an initiative designed and run by Inland Fisheries Ireland as part of Fisheries Awareness Week.
When is Fisheries Awareness Week? 12 May to 20 May 2012
Where can I find out more and how to get involved? http://www.faw.ie/himalayan-balsalm-bash/
Why Himalayan Balsam Bashing?
It is possible to eradicate Himalayan balsam (not an option with most invasive plant species) from infested river catchments because its morphology and life cycle display a number of weaknesses that are uncharacteristic of such high profile invasive species. These include:
- the plant has an annual life cycle, meaning it germinates, grows, flowers, seeds and dies in the one year;
- the tall plant has a shallow root ball so easily removed by pulling;
- the plant has no natural defence mechanisms, such as thorns or bristles, to make pulling difficult or hazardous;
- the majority of the seeds germinate after one year and
- seeds are the only propagation method of this species.
The combination of Himalayan balsam attributes described above means it is possible for large, well organised groups to physically remove the plants from long sections of river corridor. This over a two year period will deplete the seed reserve within the catchment. This represents an enormous conservation advantage to the aquatic and riparian ecosystem that will preserve the river banks from erosive effects of winter floods.
How to successfully remove Himalayan Balsam from your river bank
The following procedure should apply:
- Balsam bashing programmes should be scheduled before the plant flowers and, certainly, before any seed pods are set. The ideal time is from about mid-May to the end of June.
- On river banks, plant removal should commence at the farthest upstream site from which the plant was recorded and work progressively downstream.
- The teams of balsam ‘bashers’ should be alerted to any risks or hazards that may exist in the targeted area (e.g. uneven banks, steep-sided banks, animal burrows, dense nettle or bramble beds, etc.) before pulling starts.
- Each balsam ‘basher’ should be equipped with strong boots or wellies, long robust trousers or leggings (to ward off the unwelcome attention of nettles or brambles), long sleeved upper garments and long durable gloves (for the same reason).
- As the plants have a very shallow root ball, they are easily removed from the soil by gently pulling. However, in order to ensure the plant does not break when pressure is exerted on it, it is recommended that the ‘basher’ bends and grips the stem about 1 metre above the ground. Here, the stem is relatively thick and should not break when pulled. As the plants tend to grow in dense patches, it is often possible to remove two or more plants in the one go. The minimum of pressure is normally required to remove the root in its entirety from the ground.
- Having removed the balsam plant from the ground, it should be thrown landward, away from the river, where another team will gather the plants into large piles
- The piles of Himalayan balsam plants may be left in situ beyond the bankside, if permission from the landowner is granted. Covered with a layer of jute or hession material in order to eliminate light will hasten the demise of the plant and ensure that it will not flower and set seed (it is not uncommon for plants that have been removed fully from the soil to put all of their remaining energy into flower and seed production before they die.) The jute will rot down with the composting balsam plants. Where it is not possible to leave the plant piles in situ, they will be transported to suitable licensed composting facilities.
- The day should end with a hearty barbeque, some cold drinks and a rousing sing-song.
- As the seeds of the Himalayan balsam can remain viable for two years, it will be important that all participants put the date for the next balsam bash in their diary and bring a friend along to the same site in 2013.