Tree Identification – Top Tips
This article is part of a new series of posts about tree identification. A journey that often begins with the casual question “what kind of tree is this?”, a question that can lead to a surprising new hobby or a lifelong passion.
The journey into tree identification
At first, there are some easy species to identify – like ash, holly, oak, hazel – each with their own unique leaf shapes and characteristics. The next step is often to learn the different native species of tree within a genus (a grouping of similar tree species), for example learning our two native oak trees: the English oak (Quercus robur) and sessile oak (Quercus petraea). You then find an oak in your local park that doesn’t match at all, try to look it up and discover there are over 600 species!
A few good things to know
It is not the aim of this article to go through how to identify any particular species of tree, more to provide a bit of further reading, tips and tricks for those who find themselves captivated by this peculiar and at times confusing passtime.
With this in mind, below are a few things to remember which will hopefully help ease any potential confusion:
Diversity within a species
Individual specimens of a particular species can vary quite a lot in leaf shape, size and colour. That is not to say there aren’t defining characteristics that will always be true – there definitely are – just that you will see some natural variation which can at first be confusing.
Differences on any one tree
Identifiable features such as leaf shape can also vary on a single tree. A good example of this is the European holly tree (Ilex aquifolium), which often has its stereotypically prickly leaves give way to smoother leaves with fewer or even no prickles higher up the tree. This is thought to be a response to animals browsing on the lower branches, whereas higher up the protection is less needed.
Habitat
The immediate habitat greatly affects a tree’s growth, shape and size. The tree responds to factors like wind, nutrients and amount of available light. Trees that you usually associate with being small and understated can become quite large given the right conditions. If a tree has lots of room it will often branch out and have a broad round shape, conversely the same tree in a crowded woodland will then grow tall and appear more narrow. It is also worth noting the habitat they grow in can go against the usual trend for their kind; the ‘typical’ habitat is not always the case, more a rough guideline (for instance not all willows grow by the side of streams!).
Common hawthorn (Crataegus monogyna). sometimes a more shrub-like tree, these hawthorns are all competing for light so have grown really tall. 
A pedunculate oak (Q. robur) growing on top of a windy tor on Dartmoor. It has plenty of light to stretch out into but the wind has kept it from growing tall.
Unique identifiers
Species often have telltale characteristics that help enormously to narrow things down and let you know you are in the right area or genus of trees. A good example of this are the small glands at the base of cherry leaves, whilst these aren’t unique to cherries, they definitely help narrow it down and let you know you are likely dealing with a cherry or some other trees in the prunus genus that also have this trait.
Reference books are rarely complete
Just because the book or app you have has four possible species, it doesn’t mean it is complete, though conversely sometimes it is. If things don’t quite fit try looking in other books and searching online.
Our cities are arboretums
It’s amazing the variety of trees you can see in urban areas, roadsides and parks. From rare elms to narrow leaved ash and pin oaks, it definitely pays to think beyond the usual natives. It’s also worth noting that some cities have publicly available records of tree plantings, Bristol being one of them: https://www.bristoltrees.space/
Turkish hazel (Corylus colurna) 
Purple Beech (Fagus Sylvatica Purpurea) 
Ulmus ‘New Horizon’, a hybrid cultivar resistant to Dutch Elm Disease. Turkey Oak (Quercus cerris) 
Deodar cedar (Cedrus deodara)
Naming
A tree’s common name isn’t always accurate in terms of it’s true categorisation, an example being western red cedar (Thuja plicata), which isn’t actually a cedar. Common names are also sometimes different in other countries, which can get quite confusing, especially when searching online. An example of this would be the trees in the Tilia genus, which we call lime trees, whilst they are often known as linden in Europe and basswood in North America.
Hybridisation
This is something which isn’t often talked about but worth remembering, particularly for certain species (like limes and whitebeams). For example it can be hard to find a true large or small leaved lime, particularly in urban areas, with most trees you encounter being a common lime, a hybrid of the two.
The list is endless
It is important to remember that there are many, many different species and variations between species, plus factors like hybridisation that need to be taken into account. For this reason you are always learning and there are always surprises in store! As with a lot of life, it’s all about enjoying the process.
In the upcoming months we will be writing more about tree identification and also featuring some of the exotic species we have in our woodland – so more coming soon!
Recommended resources:
Look-up any tree in Bristol!
https://www.bristoltrees.space/Tree/
A thorough and comprehensive collection of web pages covering the most common British trees:
https://www.woodlandtrust.org.uk/trees-woods-and-wildlife/british-trees/
My personal favourite tree ID book, great for exotic species and natives:
https://www.waterstones.com/book/collins-tree-guide/owen-johnson/david-more/9780007207718