The Scottish Invasive Species Initiative has tackled invasive plants along rivers and watercourses in northern Scotland since 2018. Working across 43 major river catchments and over a third of mainland Scotland, it is the largest invasive non-native species management and control project in the British Isles. The project operates on a landscape scale and targets key invasive plants species including: giant hogweed, Japanese knotweed, Himalayan knotweed, Himalayan balsam and American skunk cabbage.
To operate successfully on this scale we must be systematic and organised in our approach to plant control. Most obviously we need to identify the uppermost source (or sources) of each species in the river catchment and begin from there. Invasive plants in the wider environment, often introduced via escapees from ornamental gardens or in discarded plant materials, can readily spread downstream by seeds or rhizome fragments carried in the water flow. In this way, they can become widespread in a catchment using the river as their distribution highway and have detrimental impacts on biodiversity, local communities and economies. Starting control at the upstream sources and moving downstream from that point helps prevent reinfestation of cleared sites and enables us to work toward eradication.
This all sounds fantastic in theory – but how do we put it into practice? The realities of implementing this basic strategy can seem overwhelming when faced with multiple species infestations in multiple tributaries – and when accumulations of species in lower rivers are very visible and scream for attention. To get the job done successfully we need to harness and coordinate input from a wide variety of people. This year for Invasive Species Week we thought that, rather than talk about the invasive plants themselves, it would be useful to work through our approach to harnessing the most important asset we have in the battle against these species – people!
Here’s how we approach things….
1. Our partners: the fishery boards and trusts
We are a partnership project led by NatureScot but with 10 different fishery and rivers trusts as delivery partners (and not forgetting the University of Aberdeen as our academic partner). The trusts employ our team of Project Officers and provide essential local support and knowledge of the catchments in which we operate – and of the people who live and work there too. Some partner trusts have controlled invasive plants in predecessor projects and made good progress in identifying the sources and controlling the upper infestations. Partner staff assist with our hands on control work and provide invaluable support at the height of the plant control season.
So, first things first, we have established and reliable local partners with local connections and knowledge of the catchments we work in.
2. The project team
The next step is to add a team of dedicated Project Officers. Our team identify and confirm sources of infestations; develop a management strategy and plan of action for each catchment; collaborate effectively with relevant stakeholders; organise training courses for volunteers and landowners; ensure all intended control work is completed and, essentially, be the eyes, ears and mouth (!) of the project on the ground!
Our Officers coordinate and carry out much of the practical control work themselves or alongside other individuals and organisations, and ensure our work is strategic and effective. They keep records of chemical use, time spent on control work and survey for abundance of invasive plant species at control sites – all of which allow us to monitor progress over time and, crucially, demonstrate progress across years and by species.
Step two then – hire a great team and add to your local partners!
3. Contractors
Each year our Project Officers identify the worst infestations and any sites where specialist skills are required before we can move towards community-based control. In these areas, we bring in the contractors.
Contractors are often the go-to option for invasive plant control, for private landowners, organisations and projects. However, we use the contractor option sparingly. There are a number of reasons for this including:
- The need to stretch our budget as far as possible and make each £ work hard. Contractor skills cost money and so if grant funding were to run out we have no fall back option if all work is completed using these groups.
- There often aren’t enough contractors around to do the work needed! Therefore, we use contractors tactically and sparingly on the worst of sites in initial control years.
- Our desire to build capacity in communities and with volunteers (local individuals and landowners and managers) so that we have a sustainable control programme delivered by those most invested in each area and catchment. We can do this when the worst of sites have been initially tackled by expert contractors.
We also use contractors when access to a site is difficult or dangerous. For example, we have several control sites on the Rivers North, South Esk and Findhorn where giant hogweed has managed to establish itself on cliff sides, which are only accessible by top roping. Our fantastic top-roping contractors (‘Bloke’s on Ropes!’) are deployed on these sites to ensure nowhere on the river is left untreated.
Next ingredient in the mix then is expert contractors deployed to the worst or most technically challenging of sites.
4. Collaborate with other organisations
Our catchments cover large areas and within each are different landowners and stakeholders to collaborate with. By working with organisations such as the Scottish Wildlife Trust, National Trust for Scotland, Abernethy Trust, the RSPB, Forestry and Land, NatureScot and local councils, we are able to make progress more rapidly than we would do on our own.
Organisations such as these own and manage land and are invaluable allies in the fight against invasive species. Our team works with local organisation staff to carry out control work annually and, once the problem has improved, look to them to maintain and take responsibility for on-going management. To support this handover process we can, for example, provide training which enables staff to carry out control work independently of the project or lend equipment or supply chemicals to remove barriers to participation.
In recent years, we have also collaborated with Perth and Kinross Council and Moray Council to tackle infestations of invasive plants on the Almond, Findhorn, Lossie and Spey rivers. For example, the River Almond control project, which began in 2023, is funded by Perth and Kinross Council and jointly managed by the Council and Scottish Invasive Species Initiative staff. There has been a fantastic response within the local community with many enthusiastic volunteers joining to help with control work – you can find out more about this project here.
So, after partners, staff and contractors we add local organisation collaboration to the mix – and then add communities!
5. Work with communities
Community groups are an integral part of the Initiative, helping to control invasive plant species in their local area. Such groups do not normally own the land they help to manage but take ownership of their local environment and give their time, passion and enthusiasm to the cause.
Similarly to land-owning organisations, we provide training, advice, practical support and, where possible, look to hand over responsibility of sites for groups to manage independently. Some of the groups we work with include Green Hive in Nairn, the Upper Tay Paths Group and the Fearnan community group in Perthshire, various local angling clubs, the educational charity Wild Things, and the ‘Beauly Balsam Bashers’ and ‘Bolland’s Balsam Bashers’ on the River Dee. The enthusiasm and commitment for local places within such groups, we believe, exists in many communities and groups and so our role is to support such groups and to translate and harness their goodwill and passion to contributions within a wider control programme.
So having now added community groups we turn to individuals committed to making a difference – volunteers.
6. Volunteers
We consider anyone giving up their time for the project to be a volunteer. However, we give special recognition here to everyone who has signed up with the project and given up their time to help tackle invasive plants. Hundreds of people from across the project area join us every season to help with plant control – their contributions allow us to control larger areas than would otherwise be possible and help us to push control operations further downstream and work towards eradication.
Volunteers come in all forms – students and early stage careerists looking for experience to enhance employment prospects, people with time on their hands wishing to make a difference in their local area, retirees giving something back locally or enjoying the social interactions of volunteering – and many more besides. We look to provide safe and enjoyable volunteering activities with a purpose and are happy to have supported many to gain employment (with the project and elsewhere) and secure formal qualifications and skills for use in the future.
The final people ingredient to our plant control programme mix is that of landowners and land managers.
7. Landowners
Last but certainly not least – landowners. We work with landowners all the time as we need their permission to undertake any work but they are also integral to our long-term sustainable control strategy.
We aim to identify problem areas in a catchment then control infestations with a mix of staff, contractor and volunteer contributions (see all of the above) to improve the sites sufficiently to handover responsibility for future management back to landowners. By providing training, equipment, advice and practical support in the early years, we provide landowners with the tools they need to control and, ultimately, eradicate invasive species on and from their land.
There is no legal obligation on a landowner to remove invasive plants from their land – only to prevent the spread elsewhere. The reality is that often infestations are large and expensive to control and landowners may simply have neither the resources nor technical expertise or skills to complete control. By reducing the scale of the problem, removing barriers to action and simply asking landowners to participate and contribute, we have made significant progress.
We already have a number of landowners contributing to the project – including estates, organisations, farmers and businesses. Currently, over 60 voluntary landowner agreements are in place where landowners have agreed to take on responsibility for ongoing management of invasive plants on their land after initial support from the project. This approach has already allowed the project to move resources to new (downstream) sites with future management on early control locations delegated to landowners.
The key to success
And that’s our approach to people engagement within our landscape scale invasive plant control project. Identify the key elements, groups and individuals and look to bring them into a coordinated overall programme where they can see that their contributions are valuable and valued.
Controlling invasive plants at this scale can seem an impossible and overwhelming task but we know that real progress is possible when you have clear goals, priorities, a proper plan and, most importantly, a collaborative effort. There are many different stakeholders involved in the project and this collective effort is what allows us to make progress.
Volunteers, in all their different forms, have contributed an incredible 23,750 hours to our plant control project so far – the equivalent of >16 staff working with us for one year! However, it’s not simply just about the time – it’s important to recognise what that time is achieving in terms of invasive plant control. This collective effort has helped us to bring 1,580km of riverbank under management for our target invasive species – the large majority of this total on an annual basis. To give some context, Edinburgh to London (in a straight line by air) is 534km – so, each year, we are managing a riverbank length equivalent to three trips between Edinburgh and London!
Thank you to everyone who has helped us so far – we hope you will continue to be involved in the future.
