Good planning begins before the locations of buildings have been fixed.
If a site has a healthy large tree, the first question should not be where to plant a new one. First we should ask whether the old tree can be retained.
A new tree symbol takes seconds to draw on a plan. Growing a large tree takes decades.
A lot can happen in that time.
A large canopy provides shade, evaporates water and affects the local microclimate. But a tree needs space both above and below ground. In a dense city, that space will not appear later simply because a tree has been marked on the plan.
The benefits of trees are local too.
Finland has plenty of forest, but a tree growing a hundred kilometres away does not shade a hot street or an apartment courtyard. The value of an urban tree comes precisely from where it grows.
That is why trees should be brought into the process while there are still choices to make.
Not only at the end, when the buildings, streets and parking have already been decided and one question remains:
where can a tree still fit?