Case Studies

Sheep Grazing as a Management Tool to Control Giant Hogweed

Giant hogweed (Heracleum mantegazzianum) is a non-native invasive plant that has become widely distributed in the UK. It is especially abundant along watercourses but is also commonly found in rough pastures and…

Summary

Giant hogweed is an invasive non-native plant that is widely spread across Scotland. The Scottish Invasive Species Initiative has been managing and controlling this plant across the north of Scotland since 2018.  Whilst methods of control for giant hogweed are generally known…

Summary

The Ravenscraig to Inverugie Bridge site on the mainstem of the River Ugie was the starting point of high abundance infestations of Himalayan balsam on the river. In 2018, Himalayan balsam was well established at the site, outcompeting native flora and increasing the likelihood…

Summary

The Sheriff Burn is a small tributary of the River Don running through the village of Kintore in Aberdeenshire. 

Since 2011 Japanese knotweed has been controlled on the River Don between the villages of Strathdon and Kintore by the River Don Trust and Don District Salmon…

Summary

The Upper River Ugie mainstem site is a 7.5km double bank section of river running through farmland towards the village of Inverugie in Aberdeenshire. Japanese knotweed had formed a dense stand on the right bank in the middle of the site, shading out native vegetation and posing…

Summary

The Ury Burn is a small tributary of the River Cowie which runs through the Ury Estate by Stonehaven in Aberdeenshire. 

Several large stands of Japanese knotweed were first found on both banks of the burn along a 1.5km length in 2011.  Following this, the River Dee Trust…

Summary

The Castle Water is a significant fishing beat on the River Spey and part of the Gordon Castle Estate.  The Scottish Invasive Species Initiative identified large fields of giant hogweed behind a wall of Japanese knotweed at the site in 2018.  Whilst the Japanese knotweed along…

Summary

The Muckle Burn drains into Findhorn Bay in Moray.  Giant hogweed has been well established on the burn for many years with only limited attempts to control it. In June 2018, the Scottish Invasive Initiative identified a site on the Muckle Burn as a priority for control. This…

Summary

The Stuartfield Burn is a tributary of the South Ugie Water running through the village of Stuartfield in Aberdeenshire.  In 2018 the site was identified as the most upstream point of giant hogweed on the burn and a potentially significant seed source of giant hogweed…

Summary

The Brae Water (Beat 3) site is a significant fishing beat on the River Spey and part of the Gordon Castle Estate.  Giant hogweed present was identified as a priority for control by the Spey Fishery Board in 2012 and the Scottish Invasive Species Initiative in 2018.  The site is…

Summary

Kellas Estate, on the River Lossie in Moray, marks the upstream limit of high density invasive non-native plant species – particularly Japanese knotweed - in the catchment.  Whilst some further stands exist upstream these are sporadic, isolated and under management control.  At…

Summary

The North Ugie Water is a major tributary of the River Ugie which runs through the village of Strichen in Aberdeenshire.  Himalayan balsam, which had become established in the area around Strichen, was outcompeting native vegetation and increasing the risk of bank erosion.  As…

Summary

The Lemno Water is a tributary of the river South Esk in Angus.  In 2018 it was identified by the Scottish Invasive Species Initiative as a significant source of giant hogweed contributing to the large-scale hogweed problems experienced downstream on the South Esk as well as…

Summary

This case study looks at the project set up in Beauly to encourage the public to get involved with impromptu Himalayan balsam pulling while out and about on walks.  Informative signage and a series of large sacks (to collect pulled balsam stems) were used to inspire and support…

Summary

In response to the need to tackle invasive Himalayan balsam on the lower River Beauly catchment the Beauly Fishery Board worked with local land managers and community volunteers to set up the ‘Beauly Balsam Bashers’ – a volunteer-led group, working under the guidance of the…

Summary

The Moulin Burn is a small tributary of the River Tummel which runs through the centre of the town of Pitlochry.  In 2018 the burn was identified as the most upstream source of American skunk cabbage in the Tay catchment – the plant having infested the burn from ornamental…

Summary

The Aberfeldy site on the upper River Tay is a 1.5km single bank section of riverbank in the town where Japanese knotweed was beginning to establish in a dominant fashion along the golf course side of the river.  There was a risk of further spread which, had this been allowed to…

Summary

This study examines the community response in the crofting township of Laide in Wester Ross to the challenge of managing and controlling the invasive non-nature species Himalayan balsam which had become established along the Sand Burn.

As the catchment is made up of a…

Summary

The Inglesmaldie site is part of the larger Inglesmaldie fishing beat on the River North Esk.  The beat has been divided into sections to better facilitate the control of giant hogweed which is present throughout.  This giant hogweed infestation at Inglesmaldie has been…

Summary

Newtyle is a 1.6km river section in the middle Tay, lying between Dunkeld (upstream) and Caputh (downstream).  The section was infested with Himalayan knotweed which had reached the site from an upstream ornamental garden.  Having reached Newtyle mechanical control was used…

Summary

The Dunkeld Bridge site on the River Tay was dominated on both banks by Japanese knotweed which was impacting biodiversity, limiting public access, exacerbating bank erosion and contributing to the further spread of the plant.  …

Summary

This case study from the Rosy Burn – a small, low amenity tributary of the River Deveron in Aberdeenshire - looks at how low motivation amongst neighbouring landowners to tackle a shared Giant hogweed problem was overcome. 

Commonly, and understandably,…

Summary

White butterbur is an invasive non-native species that is particularly prevalent across the North East of Scotland and causes serious environmental impacts along riparian corridors.  To determine the best method of plant removal, two trial sites have been created…

Summary
The need to control Himalayan balsam and Japanese knotweed along the River Bervie in Aberdeenshire required the engagement and mobilisation of a community volunteering effort and partnership to be effective. The Scottish Invasive Species Initiative met with several…

Can sheep be used as a form of chemical-free, low intensity giant hogweed control?

Summary

This trial is a practical experiment to investigate how best land managers could use sheep to control substantial giant hogweed (Heracleum mantegazzianum)…