Sometimes there are young trees growing on a branch or trunk of an older tree – some people call them cuckoo trees, and some people call them air trees. Maybe a bird has carried the seed there, or maybe it’s the wind. Here are three air/cuckoo trees. The left photo is of a young rowan tree, growing in the dip of a large hollow branch. The middle photo is a Scots pine, quite well established and growing happily right in the middle of a dead oak trunk.
The right photo is a birch tree, growing in the middle of the trunk of this living tree. The trunk is dead, and is surrounded by living bark. This dead trunk stops part way up the tree, and is filled with debris and decaying wood. The birch tree’s roots will be anchored in this and will draw nourishment from it.
This last tree has a birch air/cuckoo tree growing in its short trunk. At first glance you might not notice it, and think that it’s all oak leaves that you’re seeing as you walk by. But there’s a definite difference. From one side in particular the young trunk looks different – very straight up and smooth, compared to the oak’s branches and twigs.