Tree work is dangerous

Warning

If you have to get onto a ladder to carry out the work, the tree is too large for you to prune.
If the branch is over 2" in diameter, you are advised not to attempt to carry out the work.
Never work on trees in close proximity to power lines.
Never use a chainsaw.
Never attempt to carry out work on storm damaged, decaying or dangerous trees.
The elements of height, fall and use of cutting tools make any tree work potentially hazardous and there are many areas of tree work which require professional tree contractors.
Finally - Know you limitations and the limitations of your equipment.
You are always advised to employ a competent, experienced / qualified, fully insured arboriculturalist / tree contractor.