Heather Beaton, RSPB Scotland Uists Warden, sheds some light on non-native plant removal and why it is so important for protecting our wildlife and unique habitats.

Rhododendron removal: Restoring Uist's rare woodland

Non-native plant removals can sometimes be controversial. Questions are asked as to why certain species need to be removed, and whether they’re actually causing harm.

Now, I am no scientist, but today’s work was one of discovery. We were clearing an area of Rhododendron ponticum at Loch Druidibeg, on South Uist. Rhododendron is a non-native tree from the Middle East, and it swaths many of the coastal regions of Scotland and Ireland in purple flowers.

Photo: Heather Beaton

The plant was incredibly popular in Victorian times, which is when many large estates planted it, thinking it was good for pheasant and woodcock cover. However, rhododendron is toxic to many animals and without any herbivore able to keep it in check, it spread and spread and now huge areas of land are suffering due to its presence.

Here on South Uist, it was a similar story, as it was planted as part of an ornamental woodland. Now we’re working to remove non-natives in order to give the (very rare) Uist woodland a chance, and so the ‘rhodie’ must go.

This project has been going on for over five years, and the original rhododendron were dispatched using stem injection. This method puts pesticide straight into the heart of the tree, with no further contamination beyond the target plant. These newly dead trees were left, and we’re now working to clear these dead plants to access and remove the regrowth that’s sprung up from the roots – no one ever said rhododendron was easy to get rid of!

This small patch has been needling away at our conscious for a while, as it was the main source of seed at the eastern end of Loch Druidibeg. But no longer. It has been (almost) vanquished.

Removing the 'rhodie'. Photo: Jamie Boyle

Two days of dedicated rhodie-removal, using brute force with the back-up of tools, got the bulk of the trees out. In the middle of the thicket we found some treasure: an ancient rowan tree and two hazels. These are the first hazels we’ve discovered in this area which signify a major turn up for the Uist woodland. To protect these trees, we left a border of dead rhododendron around the edge of the area, to prevent deer gaining access and causing harm. But I also found some interesting things.

The rhododendron plants were dead, but so too was the land around them. There was very little decay, even though the trees had been dead for over five years, and there were no bird’s nests, not even any insects in the leaf litter.

All under the rhododendron was preserved in time: without decomposers – worms, millipedes, wood louse – time had frozen. Pulling together piles of leaf litter, I didn’t even see a spider.

The lack of evidence of bird’s presence becomes clear: there’s no food. Rhododendron, dead or alive, does not support other life here in the UK. It creates un-woodland, where the shade and the toxicity of the plant itself discourages other creatures from making it their home.

Photo: Heather Beaton

The rowan and the two hazels have been freed from this, but there was evidence of other individual trees that have succumbed. Their deaths are probably due to lack of light and increased competition with the Rhododendron, but we’re paving the way to make it easier for these native species in future.

It was essential for us to burn the rhododendron: without burning we’d be left with huge piles of dead wood that wouldn’t decay, and wouldn’t support any life in the meantime. Without burning, we wouldn’t be able to reclaim the land for native woodland, and we’d have to leave the dead stems in situ, allowing the fresh regrowth to mature and continue to seed.

To conclude, non-native removals are not always simple. In fact, it can be extremely difficult to remove plants that have gotten a foothold, and the reasons for eradication are not always as clear cut as it has been here, at Loch Druidibeg. The non-native removal is ongoing here, but the positive impact we’ve had so far is incredibly inspiring, and gives me real hope for the future. One day, this will no longer be dead woodland. One day soon this woodland will be rich in flora and fauna and it will make all this struggle worthwhile.