Living Bark

One of my favourite native trees here in Scotland is the Aspen (Populus tremula). With its gleaming pale branches and tembling leaves this is a beautiful species. Ecologically, aspen are considered a keystone woodland species and in Scotland they have been found to host at least 100 species of fungi and a further 130 species of lichens (see EADHA ffi) as well as a noted food of beaver. Sadly aspen have suffered heavily from deforestation and grazing pressure, often limited to inaccessible cleuchs and cliffs where the sheep and deer cannot reach.

Thank goodness then, there are wonderful people out there working hard on helping this species with great conservation work being carried out across Scotland by amazing organsiations such as Affric Highlands, Allerdale Rewinding, Borders Forest Trust, and Trees for Life. 

As well as lots of replanting, Trees for Life have recently made a major breakthroughfor the future biodiversity of Scotland's forests through a pioneering technique to induce aspen to flower. The resultant seed will help with future reforesting as well as ensuring greater genetic diversity across Scotland where aspen rarely if ever flower.

On a recent visit to the Dundreggan Rewinding Centre our guide told us about the amazing photosynthetic properties of the aspen bark. The very next day on tree recording excursion for the Woodland Trust's Ancient Tree Inventory, we spotted these fabulous specimens, clearly showing green photosynthetic bark on some of the trees. I'd never seen this before and it was mostly on the younger ones although I wish we'd recorded more details about which side of the tree this was on as I think there was a bias.

Already the leaves had gone so here is a taste of what they can look like earlier in the autumn. Lots of the more mature trees there also have fungi around their root bases and as we measured trees and took photos we discovered the UK Champion tree was a champion no longer, only a stump covered in fungi remained. This is sad however these trees are no long-lived, sure as a clonal colony they can be very long lived, but individual trees only live to around 100 years. 

One of the nearby trees may now hold the title or maybe the true champion is growing quietly somewhere in another valley? Let the tree hunting continue!