When Bristol City Council (BCC) decides to plant a new tree in a public space they use a structured process when deciding what sort of tree to plant.
This is based on right-tree-in-the-right-place principles which aim to ensure a balanced, bio-diversity of trees across both the local and the overall urban tree population – BCC curates over 52,000 trees in the Bristol urban area.
The Council also uses a 30:20:10 guide when selecting a tree species -choosing no more than 30% from any family, 20% from any genus and 10% of any species. Their tree planting guide aims to discourage thinking first about what species to plant – but poses the question What do you want the tree to do? They aim to promote a structured and sequential selection process that follows a logical decision path:
Function? => Diversity? => Design? => Species? => Support? => Placement?
Using these principles, the Council’s tree officers generally try to steer local communities away from choosing a tree species in the first instance, but instead seek to encourage them to decide where trees are to be planted and why. BCC can then match the species to the need, based on their extensive experience of what grows best where, what the likely cost will be (not just the cost of the tree, but also the costs involved in protecting and caring for it once it has been planted) and how the chosen tree will perform over its lifetime.
Looking at the 4,880 trees planted by BCC since 2008, this is what the species/genus/family distribution looks like:
You can also take a look at these links if you would like to learn more: