Example:
External and Internal View
First picture to the right shows external view of twin leaders with included bark.
Second picture shows internal view of included bark. There is no connection from one branch to the other between the two arrows. These unions will fail. The weaker they are the more swelling can be seen at the base of the inclusion.
Example:
External view
The picture to the right shows a very weak branch with extensive reaction tissue at the base of the union and at the sides of the trunk. Red arrows.
Trees such as this are extremely close to failure with or without the increased load provided by storms.
We know these trees will fail – it is only the time and day that is unknown. Such trees are not suitable in an urban environment and must be removed. Maintenance pruning, the removal of one of these stems within a few years of occurring will prevent this hazard occurring and allow the tree to fulfil its full life expectancy.
