Tremendous support, a lot of hard work and community participation has made massive in -roads into eradicating the invasive plant species Himalayan Balsam from a 32 acre site on Cemaes Head in North Pembrokeshire.
Building on previous success at tackling another invasive plant species (Japanese Knotweed), St Dogmael’s Community Association received £22,650 of SDF funding over two successive plant growing seasons to remove, prevent the spread and contain the over-whelming growth of Himalayan Balsam on the challenging terrain at Cemaes Head.
Techniques employed were site dependent and included flailing, chain sawing, brush cutting and hand pulling as appropriate. All the hard work and unbreakable determination has successfully reduced the occurrence of the plant from a density of 350 plants per m2 in places to just occasional rogue plants and isolated occurrences.
Photo: Himalayan Balsam in flower and with seed heads
Each plant can generate anywhere between 600-2,500 seeds. It might look pretty but it colonises quickly; displacing native plants and consequently adversely affecting biodiversity, soil stability and water quality.
Photos: Field before and after flail mowing by contractors.
This was necessary because the terrain in places is very difficult, with steep slopes and decades of bramble and blackthorn growth.
Photo: Volunteers brushcutting
After the first year of the project, surveying the area revealed the density of Himalayan Balsam had reduced significantly per m2 of land area covered, from a density of between 249 – 350 plants per m2 in June 2012 to a plant density of between 4 -10 per m2 in June 2013. This improved yet further in the second year to leave isolated plants that will require follow up in 2014.
June 2012 June 2013
The positive results observed over both years have demonstrated the effectiveness of using a combination of different approaches dependent upon the different habitats, slope of the land, density of Himalayan Balsam and amount of bramble, blackthorn and bracken growth.
During the two years of funding, training was given to local/young people in the practical management of invasive species but also in brush cutting (eight people), chainsaw work (two people), first aid (ten people). In return the trained individuals donated many hours of volunteer time to the project. This aspect of the project delivered unexpected socio-economic benefits in addition to the anticipated environmental benefits. It greatly improved the confidence, well-being and employability of participants and has led to three of the volunteers securing full time occupations using the skills they learned during the project.
The long term aim is to completely eradicate the species from the area. This will however require further follow up and extension work to include the adoption of conservation land practices by land owners. Follow up is required to clear late germinating seeds as well as rogue and isolated germinating plants that were missed by the project. It is hoped that some landowners will enter into land management agreements with Pembrokeshire Coast National Park Authority. Ultimately the cleared land will either be returned to productive agricultural land or be allowed to regrow into a more natural habitat supporting native species of plants with much improved biodiversity.
Those involved will continue to share best practice and hopefully inspire others to take action.