Salix is a fancy name for the willow tree family. Willows are a diverse family of trees with soft wood. Some willows, like the weeping willow, have drooping branches. Others, like corkscrew willow, have upright branches that curl and contort. Because willows are softwoods, pruning is vital to maintaining a willow tree's long-term health. Pruning will give a willow tree a stronger frame and will encourage thicker branch growth. Despite the varying shapes of willow trees, you should follow the same pruning practices for all willows.
Prune your tree in late winter when the tree is dormant. This will prevent the tree from going into shock and declining in health from the pruning.
Sharpen your pruning tools, including a hand saw and branch loppers before pruning willow trees. Pruning with sharp tools will help prevent bruising and other damage. Sterilise the tools by wiping them with a solution containing one part bleach and nine parts water.
Examine the tree and mark each branch that you plan to remove by tying a piece of survey tape to it. Plan your entire pruning session in advance before you cut your first limb. Never remove more than one-third of the tree’s total growth. Select branch loppers for limbs less than 3.75 cm (1 1/2 inches) in diameter. Use a hand saw for branches less than 15 cm (6 inches) in diameter. Use a chain saw for larger branches.
Remove weak and spindly branches, branches that are broken or branches that are diseased by cutting the limb just above a healthy bud that faces outward. The bud will sprout a limb that will become a new dominant leader.
Cut away tiny trees that form in the willow’s root system. These trees will steal nutrients from the large willow.
Thin the tree’s canopy by removing any branches that grow inwards or rub together, to promote circulation through the tree. Remove branches that join a tree at a weak angle before the branches can break. A limb that grows from the tree at a weak angle includes one that branches out from the trunk at less than 90-degrees. Branches such as this have a propensity to break in high winds.