Tree of the week | Common Ash – Fraxinus Excelsior

July 9, 2010 0 By Richard

I thought it would be fun and interesting to pick one tree a week and publish a quick article about it. To start off I have decided on my favourite (for no particular reason) tree at the moment, the Common Ash or Fraxinus excelsior by its botanical name.

Ancient Ash Tree

Ancient Ash Tree on flickr

The Ash family of trees are part of the Oleaceae family which also includes olive trees, lilacs an jasmines. There are 600 species in the Oleaceae family which includes 60 different species of ash.

Most Ash trees will have leaves opposite each other and the leaves will originate from a long central stem or axis. This type of arrangement is known as  Pinnate, latin for feather or wing. Common Ash trees will have a black bud making them easy to identify in the spring. Just remember, ash from a fire is black and so are the buds of the Ash tree. Another distinguishing feature is the fruit which hang in bunches of single aerodynamic ‘keys’. Maple trees also have ‘keys’ which occur in pairs. Luckily maple trees have completely different leaves making it difficult to confuse the two species.

Ash trees have many uses and are one of the best sources for firewood. Ash trees contain more oil and burn better than other trees because of their oil content. This is because they are closely related to olive trees, known for their olive oil, and Ash can be burnt even when green (freshly cut/unseasoned timber).

Ash trees are also used for making electric guitars, parts of cars and interior wood work. Ash is a very tough wood whilst it is also elastic. It used to be common to use Ash wood in the structure of cars because of the elasticity, now it is less common but some cars still use wood over modern alternatives. The elasticity of the wood also makes it great for making bows (the weapons) and the wood has also been used to make walking sticks.

Riverside Ash

Ash tree typically have leaves in an opposite arrangement

Unfortunately Ash does not last very long outdoors, it will normally decay and be useless within five years.

If you have been out and about in the UK this summer then you will have seen an Ash tree. The Common Ash also called European Ash is, as the name suggest, common across Europe  although it does not fair to well in the cold and hot extremes such as northern Scandinavia and southern Iberia.

The Common Ash used to reach heights of 45 meters but now 30 meters is a good height for an Ash Tree to reach. They have smooth curving branches and airy canopies which does little to suppress Ivy, which is why they are usually Ivy clad.

Younger trees have a smooth bark which slowly turns into the criss-cross pattern found on older  specimens which can have a  trunk up to 2 meters in diameter. There are a few Ash trees older than 250 years but these should be considered an exception rather than the rule. The largest known Ash tree is in  Clapton Court which has a staggering 9m girth. Many trees of different ages are disfigured by black erupting bacterial cankers, a sign the tree has some degree of decay.

Ash tree in bud

Ash tree with its distinctive black buds

You may have heard of Mountain Ash which is not really an Ash tree unless (you are in Texas and are referring to Fraxinus texensis). Mountain Ash is usually used when talking about a different family of tree the Sorbus genus. In the UK Rowan trees (Sorbus aucuparia) are refered to as Mountain Ash. The leaf arrangement is similar to that of Fraxinus trees, however Sorbus aucuparia have toothed (serrated) leaves along with green fruits which turn bright red in late summer.