How to Prune Blue Oak


Blue oak or Quercus douglasii got its name for its blue-green foliage. It is also called mountain white oak, iron oak and mountain oak. The tree is usually found in California, in extensive open areas in the interior foothills. It is adaptable and grows well in loamy, dry, gravelly or rocky soils. Pruning blue oak is a good idea if you want to remove diseased or insect-infested wood or improve the appearance of the tree.

Step 1

Consider the form of the blue spruce, which is considered spherical. This means it has many lateral branches that may compete for dominance. You need to take this into account because if you try to make the tree into an unnatural form, you'll have to do continual maintenance.

Step 2

Prune blue oak when they are young to produce a strong structure. As they mature, the purpose of pruning is to maintain the tree structure, health, form and appearance.

Step 3

Plan to make cuts at the node, which is where one twig or branch meets another. Each spring, growth will start with buds, and twigs grow until there is a new node.

Step 4

Thin the crown to increase the amount of light and air that gets to the tree. During this process, you will develop and maintain the tree's form and structure. Do not remove more than one-quarter of the crown at a time or you may cause stress and excessive production of epicormic sprouts.

Step 5

Keep all branches that are attached with strong U-shaped joints. Remove those branches with narrow, V-shaped connections because they are weaker and are likely already cracked.

Step 6

Achieve crown raising by removing all the branches that are facing downward, at the bottom of the tree. This will provide clearance for pedestrians, traffic and lines of site. The tree will also have a neater appearance.

Tips and Warnings

  • Don't use a saw or pruning equipment without wearing proper safety equipment such as goggles and gloves.

Things You'll Need

  • Ladder
  • Saw or pruning equipment
  • Goggles
  • Gloves


  • USDA Forest Service
  • Forestry Resources Extension
  • Sacramento Tree Foundation
Keywords: prune, blue oak, tree

About this Author

Based in New York State, Kelly Shetsky started writing in 1999. She is a broadcast journalist-turned Director of Marketing and Public Relations and has experience researching, writing, producing and reporting. She writes for several websites, specializing in gardening, medical, health and fitness, entertainment and travel. Shetsky has a Bachelor of Arts in communications from Marist College.