Instead, the modern approach is that a tree should mean anything ‘that would ordinarily be regarded as a tree’. Thus it would not include a ‘shrub, a bush or scrub’ but it ‘includes small trees’. The end result is that even the smallest sapling can be protected by a Tree Preservation Order. 



The logic of this means that a sapling becomes a ‘tree’ from the moment it first emerges from an acorn, which means there is no longer an argument about when a sapling is large enough to count as a tree.