Winter tree pruning provides many benefits that summer pruning does not offer. When pruning trees in the summer, it is necessary to drive on grass areas to access the tree with a boom lift. If the ground is soft, the ground can easily be rutted during pruning. During winter tree pruning, the ground is frozen, which reduces or eliminates ruts all together. It is also easier to access the branches of the tree during winter tree pruning. When the foliage is off of the tree, any damaged branches are more visible. It is easier to spot dead or dying branches or branches that have suffered disease, insect, mite, animal or storm damage. Some of this damage might not be visible during the summer when the tree is fully leafed out. Since trees are dormant during the winter, wounding will be reduced. Winter tree pruning will only expose a wound for a short period of time as opposed to summer pruning when the tree is actively growing. When the tree comes out of dormancy, it can concentrate on healing as opposed to maintaining the health of the foliage. The resources used to feed the foliage can be better put to use healing the tree from winter tree pruning.
Approximately 90% of deciduous trees can be pruned during the winter when they are dormant. As soon as the trees lose their foliage and go into dormancy, you can begin to prune. Winter tree pruning can be done all the way through winter up until spring. Just before the buds on the branches of the trees start to expand and leaf out for the year, pruning should be halted. Evergreens on the other hand should be pruned when they are actively growing, since they never fully go dormant. If you prune evergreen trees in the winter, you may notice tip burn on the branches.
Winter tree pruning reduces insect damage.
In the winter when your trees are dormant, so are the insects that damage them. If you perform winter tree pruning, you will most likely not have to worry about insect damage occurring to the wounded area of the tree. Insects will be more apt to feed on these wounded areas of the tree. So by pruning in the winter, you will not have to worry about insects attacking these areas as the insects will not be active at this time. Disease in the winter will be almost non-existent as well. Cooler temperatures will keep most diseases from being active or spreading.