Traditionally, wound dressing or pruning paint is used only on cuts larger than an inch in diameter.  However, scientists have found that wound dressings are strictly cosmetic and have little to do with preventing insect or disease damage to the wound area.  Pruning paint may, in fact, slow down the healing process.  In general, wound dressings are not recommended or necessary, with one exception.  On oak trees from the end of February until the end of June when the oak wilt disease is prevalent, wound dressing should be used to help prevent the bark beetle from spreading the disease through the pruned surface on a tree.