Are all trees regulated and exactly what defines a “tree?”
In general, only trees that have a diameter at breast height (DBH) – i.e., a trunk diameter at 4.5 feet above the ground – of 6 inches or greater are regulated as trees in the City of Issaquah. Anything with a DBH smaller than 6 inches can be removed, pruned or altered – as long as it is not located in a critical area or buffer. There are a few exceptions to this rule that you should be aware of. First, when small trees (trees with DBHs smaller than 6 inches) are planted as part of mitigation for tree removal, these trees cannot be removed or altered until they have grown enough to meet criteria to be defined as a tree (i.e., until they reach 6 inches DBH). The City wants trees that are planted as mitigation to be protected until they actually become a regulated tree. Second, trees with multiple leaders at breast height (4.5 feet above the ground) may have a leader that is smaller than 6 inches and yet still be regulated as a tree. This is because trees with multiple leaders use the average leader diameter – the additive total diameter of all leaders divided by the number of leaders – measured at 6 inches above the point where the leaders digress. (And while we are discussing DBH and trees, please remember that all Landmark Trees – trees with a DBH greater than 30 inches – require an approved tree removal permit for removal or alteration.)

Show All Answers

1. Do I need a permit to remove a tree?
2. Is there a tree removal fee?
3. Can any tree be removed from my property?
4. How do I know if a tree is located within a critical area, buffer or NGPE or if the tree is otherwise protected?
5. Are all trees regulated and exactly what defines a “tree?”
6. What about hazard trees?
7. Can hazard trees be removed from critical areas?
8. What about emergency situations?
9. Do hazard trees count toward my one and five year tree allowances?
10. How is tree removal on non-single family properties handled?
11. What if I need to remove trees to make way for a home expansion or other development project?
12. What if I want a tree removed from a City ROW or public property?
13. What if I want a tree removed from my neighbor’s property?
14. Are there other regulations pertaining to trees aside from tree removal restrictions?
15. What should I do if I think trees are being removed illegally?
16. What are the penalties for illegally removing trees?
17. What if a tree in or near a power line needs to be trimmed?
18. Do I need a permit to prune a tree?