Common Ash is also known as European Ash and is fairly common throughout Exeter. It is the third most common tree in the UK so you're quite likely to pass them by on a day to day basis. During the spring and summer the leaves are very showy and certainly add a splash of colour to the landscape. The flowers are also very unusual when compared to most trees and often go unnoticed which is a shame. The most interesting feature of this tree are the buds. They are a charcoal-black and very distinct - there is no tree with buds like the Common Ash. This is a great tree for beginners due to to it's distinct features all year round.
Common Ash can grow as high as 35 metres and can live up to 400 years. It's not too fussy about which soils it can grow on but it does require full sun. It is typically a very hardy tree and can withstand even the most bitter English winter. However, there is a serious threat to Common Ash which is called Ash dieback. In nearly all cases it will lead to the death of the tree. Ash dieback is a disease caused by a fungus called Chalara fraxinea. Just to give you an idea of how serious a problem this around 90% of the Common Ash trees in Denmark have been wiped out. We have around 80 million Common Ash trees in the UK, but that could soon change. Luckily we have a lot of clever people working on the case - so fingers crossed we won't lose as many as Denmark. Another problem is the larvae of the Emerald ash borer. These little critters are causing a lot of problems for Common Ash trees in North America. Millions of trees have been lost due to the destructive nature of the larvae. Touch wood (pardon the pun) we have not had any outbreaks of these insects...yet.
A photo of Ash dieback beginning to take hold. The brown patches are first signs. Credit to Food and Environment Research Agency
Although a very pretty insect, it's larvae is utter terror for Common Ash trees. Credit to U.S. Department of Agriculture
So if you do spot any Common Ash trees that are infected by Ash dieback please notify the Forestry Commission. As for the Emerald ash borer you should report it to the Forestry Commission. More details on this shiny green critter can be found here.
These are female Common Ash flowers. As you can see they are very distinct and unusual
You can see the fruit is beginning to form and the first leaves are about to open
The flowers of Common Ash are a real treat to see. They appear in the spring and are coral like formations of green and red / purple. What's interesting about this tree is that it's dioecious which means there are separate male and female trees. This is very common with the Willow or Poplar family. However, Common Ash is a little special. On some trees you can have both male and female flowers. Also, one year it could be a male tree and the next year a female tree - or vice versa. So a very diverse tree when it comes to the flowers.
Charcoal like buds make this an easy tree to spot during the winter
Flowers beginning to break out of the buds
The leaves are pinnately compound and usually have 3 to 6 pairs of opposite pairs of leaves. The leaves are light green, typically oval shaped and fairly long - normally up to 40cm. There is always a single terminal leaf at the end. The flowers always appear before the leaves - for both male and female trees. The leaves can also move in the direction of the sunlight so the entire crown of the tree can shift position - which is pretty amazing. Probably the most unusual thing about Common Ash is that it will begin to shed it's leaves when they are still green. This doesn't seem to harm the tree and is widespread for most of these trees.