Charcoal fines

The discovery of ash die back disease in the British population of ash trees has been in the news a lot lately. I hadn’t been paying too much attention, as I have had my mind on other things, and I wouldn’t recognise an ash tree if I walked past one!

But the situation is serious (and striking close to home with infected saplings being burned in Bicester) and so I thought it was time for me to learn about a tree that is very important in Britain. Ash die back affects all species of ash (which are in the Oleaceae family), but the Common (or European) Ash Fraxinus excelsior, is a native broad leaf tree that makes up around 5.5% of British woodland. The Forestry Commission also estimates there are around 12 million trees outside of woods and forests; they are at home in urban environments, with a good tolerance for pollution.

With an airy canopy, and a short season in leaf, ash trees let plenty of light through to ground level, and hence allow other woodland plants to grow – such as wild garlic and dog’s mercury. These, in turn, nurture insects and birds, so ash trees are considered to be good for wildlife.

Ash seeds (known as keys) are notorious for germinating well, and the tree can be considered to be ‘weedy’. Its timber is now considered inferior to beech and oak, but it has a long history of use and is still valued for its strength and flexibility. Ash timber is a natural shock absorber, and can be safely bent even after being seasoned. It’s still popular for use as handles on tools, and for sporting equipment such as hockey sticks and oars. Ash is also used to make furniture; more traditional uses include tent pegs and skis, coaches and carts.

Ash trees can be coppiced, on a 10-year rotation, and the straight poles are very versatile. Coppiced ash is also a good source of firewood and charcoal. There’s an ash stool in Suffolk that 18.5 feet in diameter and though to be over 1000 years old. Ash is still valued for walking sticks (known as ashplants) because of its shock absorbing properties and smooth bark, and saplings can even be grown in a special way to naturally form a curved handle.

In Northumberland, ‘creeves’ for catching crab and lobster are often made from ash, and the tree also has medicinal uses and is a source of tannin. Self-sown ash trees filled in many of the gaps left by falling trees in the great storms of 1987 and 1990, and replaced dead elms.

Mabey* notes that in Scandanavian mythology, the ash is known as Yggdrasil, the Tree of Life. In the UK it was regarded as a healing tree until the end of the 18 century.

And as if that wasn’t enough, PFAF has edible uses for ash! Apparently the immature keys can be pickled and used as a condiment (see Eat Weeds for a recipe), and the leaves can be added to tea, although it’s unclear from the reference what they would add! Leaves can also be used to produce a green dye, and the mature seeds are a source of edible oil.

So, at this point we can only hope that either the ash tree itself, or a scientist somewhere, comes up with a resistant variety that gives this disease a good run for its money. And I need to start trying to pick ash trees out in the landscape. I’m looking for a large tree, with compound leaves (although not at the moment). Flowers appear in April and look a bit like coral; at this time of year you can see bunches of ash keys, which usually hang on the tree until early spring, but given this breezy weather may have flown off…. A characteristic feature is the black, ‘hoof-shaped’ buds at the end of each twig.

*Mabey, R., Gibbons, B., Jones, G. L., & Common Ground (Organization). (1996). Flora Britannica. London: Sinclair-Stevenson.