Aspirations for aspen 

By Jos Milner, East Cairngorms Moorland Partnership Officer

Aspen are one of our most beautiful trees, turning a spectacular golden colour in autumn with leaves that shimmer on their long stalks in the lightest of breezes.  They only flower occasionally in Scotland, mostly spreading by suckers which pop up from the roots of mature trees, forming clones.  But these suckers are high on the menu for deer, livestock and other herbivores. 

The Cairngorms National Park is home to significant remnants of Scottish aspen populations. These trees are an important but relatively rare element of Caledonian pinewoods and support a host of even rarer species that depend on them. These include the aspen hoverfly, the dark bordered beauty moth and very rare mosses and lichens. The rarity of these species mean they are conservation priorities for the Park Authority and we are working with landowners and partners across the National Park to create a thriving network of aspen habitats. 

Work has been taking place to map over 3,000 existing aspen stands across the National Park, where the trees are, their age, condition and any priority species. In partnership with Trees for Life and landowners such as Cairngorms Connect and members of the East Cairngorms Moorland Partnership, work is taking place to improve the aspen population – increasing the number of trees and better connecting the existing ones.  This includes new planting to fill gaps in aspen corridors, fencing to reduce browsing pressure and managing existing stands of trees. 

Speyside is home to some of the Park’s largest aspen stands which are particularly important for the aspen hoverfly which lay their eggs under the rotting bark of large, dead aspen trees.  This species relies on a continuous supply of dead aspen wood so owners of these aspen sites are urged not to tidy up any fallen dead wood. In other parts of the Strath some mature trees have recently been fenced to protect them from beavers and the aspen population for the future is being expanded – with help from the National Park’s award-winning Junior Ranger team, 400 aspen saplings have been planted on Wildland. This continues the aspen planting efforts on Speyside which has seen over 15,000 saplings being planted in the last 20 years, including over 10,000 at RSPB’s Abernethy. 

In Deeside, on Balmoral Estate, a partner of the East Cairngorms Moorland Partnership and home to the dark bordered beauty moth, rangers and volunteers have been hard at work. Hundreds of young aspen have been planted and areas where suckers were being heavily browsed have been fenced. The moths have responded well, with 27 being counted in one night alone in one of the fenced plots. Elsewhere in the Partnership both deer reduction and fencing have proved effective in promoting regeneration in mature stands on National Trust for Scotland’s Mar Lodge Estate. Similarly, a two hectare enclosure has recently been built on Mar Estate to encourage regeneration of an old aspen woodland and stock-fenced plots and sucker protection guards within livestock-grazed fields are helping to connect smaller, fragmented stands.  

It is this on-going conservation work by a wide range of partners across the National Park that will ensure the shared futures of aspen and the species it hosts. For more information visit  https://treesforlife.org.uk/about-us/cairngorms-aspen-network/.