The entire post can be found at ArborScape Services website. 
Thanks go out to Matt Johnson and Arbor Scape Services for the excellent information and services they provide.
Unlike most major cities, in Denver, property owners are responsible for the care of “their” street trees even though they’re technically owned by the People of Denver.
That means you are responsible for obeying city tree pruning ordinances. Private trees, such as those in your backyard, have fewer restrictions, but you still are required by city ordinance to maintain and prune trees to ISA standards.
Here are the top 10 rules and guidelines you need to know if you’re pruning a tree in Denver.

  1. A permit is required to trim or remove any street tree, even if you do it yourself. There is no charge for a permit.
  2. If you have a dispute with a neighbor over a tree, it is a negotiated civil matter.  City arborists can not intervene unless a tree is a legitimate structural hazard.
  3. Right of way trees abutting your property are you’re responsibility. That includes removing diseased trees.

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