Rhododendron Eradication – Stem Injection – Difficult

Date published: 29 November, 2023

For recent changes to this guidance, please see the bottom of the page.

This is for the chemical treatment method of stem injection for the eradication of rhododendron on ground with slopes greater than 33 per cent. This is the preferred method of treatment.

For the Woodland Improvement Grant – Habitats and Species option, this capital item will be targeted at those priority areas identified as red and orange in the ‘Rhododendron Control Target Areas’ as shown in the ‘FGS (2014-20) Target Areas’ folder on the Scottish Forestry Map Viewer.

Applications for areas outwith these areas will need to make the case for being funded (e.g. by being in a priority rainforest area or including a letter of support from NatureScot). If you think you meet this eligibility criteria please discuss with your local Conservancy office.

These exceptional cases would include any designated site that is in unfavourable condition because of rhododendron, or which needs rhododendron control to maintain it in favourable condition, or is in a priority rainforest area.

The latter could include small areas of rhododendron on a site, which are not in themselves sufficient to make it unfavourable – five per cent cover is required for unfavourable – but since it spreads, any small amounts should be controlled as soon as possible to prevent future problems.

We might also consider there to be an exceptional case if there was rhododendron on adjacent land, which hadn’t spread onto a designated site yet.

Support for rhododendron control will be dependent on the applicant producing a 10 year Rhododendron Control Plan for the property (and ideally collaborating with adjacent neighbours) which will demonstrate a long-term strategy to eradicate and control invasive rhododendron including monitoring and follow up treatment.

The plan should draw on the current advice and guidance given on the Scottish Forestry website, and should reflect the structured and co-ordinated approach promoted in the new national rhododendron control strategy.

The plan must also, wherever needed, commit the applicant to working collaboratively with adjacent neighbours (Scottish Forestry woodland officers may need to verify if collaborative work is required).

This plan must be attached to your application.

The plan must include:

  • a map that details the extent and percentage cover of the rhododendron (to evidence the net area of hectares you will be claiming grant on), and categorises the rhododendron by grant type (for example: stem injection – difficult)
  • details on the control method and follow-up for five years

For the Tree Health option, this capital item is only available within Statutory Plant Health Notice areas and as dictated by the terms of the Statutory Plant Health Notice – therefore a Rhododendron Control Plan is not required.

This treatment is recommended on stems that have a greater than three centimetre diameter and can be individually accessed.

A blade or drill should be used to make a reservoir in the stem. Herbicide solution should then be injected. If a further follow-up is required this can be applied for separately.

Once the intial clearance works have been completed a capital cliam can be submitted. If follow-up works are carried out within the first 5 years of clearance then one further captial claim may be submitted. However, should any further follow-up operations be required to eradicate rhododendron beyond the first 5 years, then a separate FGS application for the Rhododendron Eradication - Follow up capital grant should be submitted.

The site must be monitored and surveyed at year four to make sure that all mature bushes have been treated and control has been achieved. Please provide the survey results and photographic evidence to your woodland officer.

The site may be inspected by Scottish Forestry at this time.

Please refer to the guidance in the Health and Safety Executive application of pesticides by handheld equipment document.

Guidance on what constitutes best practice rhododendron control can be found in the Practice Guide ‘Managing and controlling invasive rhododendron’ published on the Scottish Foretry website.

A Critical Review of Work Undertaken to Control Invasive Rhododendron in Scotland

There is also information to assist you on the Forest Research website on reducing pesticide use in forestry.

Please make sure you abide by conditions set out in the Forestry Grant Scheme claim form and guidance.

Section Changes
Main section We've replaced the spatial prioritisation map with the Forestry Commission Scotland Map Viewer.
Whole page Extending the rhododendron control target areas to include priority rainforest catchments, enabling clearance and initial follow-up control in one application

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