Black spruce or Picea mariana is a native, coniferous small tree that is slow growing and has a pointed crown that is about 30- to 50-feet tall. Like other spruce trees, the leaves are stiff, half-inch needles on woody pegs. They are blue-green in color. Black spruce are fairly adaptable and grow well in full sun to partial shade with dry to moist conditions. They can be pruned for two reasons: ornamental and health.
Know that you can prune black spruce trees at any time of year without affecting the tree's health. Removing diseased, weak or broken branches will help it thrive.
Consider waiting until the dormant season if you want to lessen sap and resin flow from the branches you cut.
Take into account the tree's natural form--pyramidal crowns. This means the black spruce has a strong central stem and branches that come out from it laterally, in a horizontal direction.
Use a saw or pruning device to cut into the node, which is the point where one twig or branch attaches to another. Keep the branches with strong U-shaped unions intact, but cut off those that are attached to another branch in a V-shape. These are weaker joints and often have cracks.
Cut off any branches that are facing downward on the underside of the tree. They prevent an umbrella appearance and look messy.
Remove any branches that look diseased or dead. Cut them at the V-shape where they meet with healthy branches.