Himalayan Balsam (HB) removal experience 2024
Now the season has finished for 2024, I thought it would be a good idea on looking back at what we have learnt from this year’s volunteer effort at trying to tackle this invasive species.
First off however a very big thank you to all who have been involved so far in helping out. We have made a start but we should be under no illusion, it is going to take quite a few years to try and irradicate the plant from the whole River Lim Catchment. Our programme this year involved five, four hour plus, weekend sessions between May and September. Our numbers of volunteers varied from 9 -18 individuals turning up on one of the days. We are going to need two or three times that number if we are going to get on top of the problem. However, for a first year’s effort thousands of plants were successfully removed.
We started in May which normally would be ok but as the weather had been colder than usual the HB was showing but only as very small plants. Sitting in wet fields picking out literally thousands of tiny plants is hard work. June proved to be slightly better where plants were up to 50cm but still in vast numbers. By July most plants were well over a meter in height and starting to flower and easy to pull up completely. The ground where they flourish is often very soft and slippery and this last year was no exception. As the plants get bigger the mass of material being removed becomes enormous. It is important to remember that HB comprises mostly of water and once deprived of water very quickly shrinks and decomposes.
We had lots of rain over the summer and the HB plants responded well to the climatic conditions with mega plants over three meters tall appearing in some areas. The seeds were beginning to set in August and it was observed as likely to be a bumper crop. A HB plant can have dozens of seed pods with each containing up to 16 seeds, multiply this by the number of flower heads on just one plant and 800 seeds per plant can be produced. The seed release mechanism can project the seeds up to seven meters from the plant. If this is adjacent to a water course it is easy to see how quickly it can get established within a river catchment. The seeds can remain viable in the soil if they reach it for up to at least two years.
Our last volunteer day was in September on a near perfect sunny day following very heavy rain for the four days previous. As much care as possible was taken in capturing the heads separately before pulling up the plant. We were astonished also to find many smaller HB plants growing and trying to flower.
This has made me think that for next year we need to approach things differently. First off, I do hope the wonderful volunteers who turned up this year will come along next year and bring others. Depending on the Spring weather will determine when we actually get started. I also think that one session a month is nowhere near enough. Currently I am proposing two sessions in June 2025 and three sessions per month in July and August. We will be more flexible on days hopefully organising some sessions at weekends and others in the week. Hopefully we can engage more landowners, together with their own families to come and help to boost numbers. If anyone knows of any local organisations or businesses which may like to hold “team building days” I am sure we can arrange sites and back up.
What I can reflect on from this last year is how enjoyable working as a team can be. A mixture of people, all from different backgrounds and interests, provides a really wonderful, outdoor healthy, social experience. Engaging in worthwhile community projects, that ultimately will benefit hugely our local environment must be a good thing . Please consider joining up next year, we would love to welcome you. Graham Roberts -co-ordinator gbroberts51@gmail.com
