BRISTOL STREET TREES
2007
Why "topping" hurts trees, often leads to decay
submitted by City of Milpitas
"Topping" is perhaps the most harmful tree pruning practice known. Yet despite its harmful effects, topping remains a common practice. Let's take a look at what is meant by topping, why topping hurts trees, and what some better pruning alternatives are. What is topping? Topping is the cutting back of tree branches to stubs or lateral branches that are not large enough to assume the terminal role. The most common reason given for topping is to reduce the size of the tree. Topping, however, is not a viable method for height reduction, and will make a tree more hazardous in the long term. Stressing trees Since the leaves are the "food factories" of the tree, and topping often removes 50 to 100 percent of the leaf-bearing crown of a tree, this can temporarily starve a tree. The severity of the pruning triggers a sort of survival mechanism. The tree needs to put out a new crop of leaves as soon as possible, and latent buds along the branch are activated, forcing rapid growth of multiple shoots below each cut. If a tree does not have the stored energy reserves to do this, it will be seriously weakened and may die. A stressed tree is more vulnerable to insect and disease infestations.
ARTICLE IN THE MILPITAS POST
02/12/2007
Following the fiasco that resulted in the removal of a line of mature Poplars in south Bristol, at least one authority knows that pruning trees needs to be done properly.