Pruning trees to build strong structure is critical to growing a healthy mature tree and avoiding dangerous or unsightly limb loss. Taking simple steps while the tree is young can prevent costly pruning in the future. Keep in mind the 3Ds, R & C: meaning remove Dead, Damaged, Diseased, Rubbing and Crossing branches to keep your tree healthy.
Structural pruning goals:
- Remove dead or damaged branches
- Select and develop a dominant leader
- Select the lowest branches in your tree and remove branches below
- Space branches along the main trunk
- Always make your pruning cuts outside the branch collar (the thick part oat the base of the stem), never make a cut flush with the tree.
Here are a few great structural pruning resources: Tree Pruning Cue Card, Structural Pruning of Shade Trees, Structural Training of Young Shade Trees, or the University of Florida Structural Pruning Guide.
City Fruit, UW Botanic Gardens, and PlantAmnesty all offer hands-on structural pruning courses in Seattle. Learn more by visiting their webpages and contacting them about their upcoming class schedule
Improper pruning techniques seriously damage a tree. Consider hiring a professional certified arborist for the job. Check out PlantAmnesty's arborist referral service.
Street Tree Pruning
Seattle Department of Transportation (SDOT) is responsible for maintaining the approximately 35,000 SDOT-planted trees located mainly along arterial streets. Care for all other trees in the street right-of-way is the responsibility of the adjacent property owner. If you or a former occupant of your home planted a tree along the street in front of your house, it is your responsibility to take care of it. Care includes watering in the dry season, mulching to conserve water and inhibit weed growth, and pruning to reduce conflicts with human activity, as well as to sustain the health and structure of the tree.
Pruning a 2” branch or larger on a street tree requires a free tree pruning permit from SDOT. For more information about pruning trees in the right-of-way, contact the SDOT Arborist's Office at Seattle.Trees@seattle.gov or 206-684-TREE(8733).
Topping a tree is not only unsightly, it's hazardous.
Stop Tree Topping
Tree topping is an outdated pruning practice that indiscriminately removes large amounts of leaves and branches. Not only does tree topping look terrible, it will cause greater and faster regrowth. Topping a tree only stimulates growth, increasing the need for subsequent work and maintenance. Tree topping also causes serious long-term damage to a tree, increasing the hazard to people and property. Certified arborists and legitimate landscape professionals will never suggest topping a tree- there are other acceptable pruning practices for keeping a tree away from adjacent structures. Avoid tree topping, and hire an ISA certified arborist.
Don't top trees!
Pruning Guide from Seattle Department of Transportation – in 7 languages
Pruning Information from Plant Amnesty
Pruning information from the International Society of Arboriculture
PlantAmnesty's referral service for Certified Arborists
City Fruit's Guide to Pruning Fruit Trees
SDOT's Online Street Tree Map
Tree Service Companies with an SDOT Annual Permit to work on Seattle street trees