Tree surgery adviceI thought it might be useful this time to describe some of the commonly used tree pruning techniques and the terminology used by tree surgeons. Most people with gardens in this area will find they have to employ a tree surgeon at some time, and this will often be at a stressful time, in an emergency situation, such as after a storm, with a tree leaning dangerously, a branch fallen off , etc.
Raised root - plate or root-pad. A tree's roots normally spread out from the trunk quite shallowly under the soil, and a tree blown crooked by a high wind may show this circular plate or pad of roots lifted on one side under the turf or soil. A tree in this condition will usually be dangerous and liable to fall completely.
Crown reduction
This means cutting back all of the branches in the crown or canopy of the tree, resulting in an overall reduction of the lenght of all branches, making the crown of the tree smaller, and usually 'tidier' , but not necessarily less dense. Indeed, over time, the new growth encouraged by this pruning will often result in a crown that is more dense.
Crown thinning
This is the removal of some of the smaller secondary branches in the crown, while retaining the main framework of branches at its original size. This technique 'opens up' the tree to let in more light, and reduce wind resistance.
Crown cleaning/clearing
This means the removal of dead, dying,damaged or diseased or overcrowded branches.Crown lifting.This is the trimming of all lowest branches in order to raise the height of lowest parts of the tree, for example to ease walking under low branches.
Crown balancing
Pruning the canopy to remove excess bulk from one side of the tree, to correct top-heavy or uneven growth.
Pollarding
The removal of all branches leaving just the trunk. New growth in response to this is in the form of a spray of young straight branches, giving a brush - like appearance. The treatment must be repeated at regular intervals to maintain shape.
Topping
The removal of all smaller branches from ends of main branches-rather like pollarding, but at ends of big main branches , instead of main trunk. A popular technique in recent years used by councils for control of street trees. Freshly done, it can appear drastic, but new growth is usually rapid.
Felling
The complete removal of the tree, usually followed by treatment of stump to prevent regrowth.
Stump grinding
The use of a special (and big) machine to grind up the remaining tree stump in site, deep into the ground allowing ground to be used again immediately. Often very useful in a small garden, but of course denying valuable wildlife habitat. Finally, a word about dead wood management.
As mentioned earlier, leaving a tree stump to rot away naturally is much better for wildlife, providing homes for literally hundreds of species over sometimes decades if the stump is big. Likewise, the removal of dead and dying wood from the crown of the tree is seen as essential management in a street or urban tree, for obvious health and safety reasons, but removes a valuable resource from the tree.
If you have the space, ask your tree man to leave all the larger cut trunks and branches, in longish lengths, in a pile at bottom of the garden. This will become a wildlife heaven for years to come.
