Red Dogwood (Cornus sp.), hardy in USDA zones 5 to 8, grows 20 to 35 feet tall, and you may choose to train it to grow with one central trunk or allow it to grow into several trunks. You won't need to worry about pruning this tree often because its pruning needs are minimal. Prune red dogwoods primarily for aesthetic reasons and to prevent spreading disease when it is present.
Prune shrubby dogwoods with colorful bark such as red osier dogwood down to the ground every three to four years to encourage new colorful growth. Clip off branches with a pair of clean, sharp lopper shears until you have removed every branch.
Prune dead branches on dogwoods whenever you spot them. Clip the dead branch from the tree at its base.
Prune crowded and low-hanging branches as necessary. Clip crowded branches at their base where they connect with a larger branch. Complete these pruning tasks in late winter or early spring before the new growth emerges.