Sunnyvale Urban Forest Advocates recommends consulting an arborist with tree related questions.
The International Society of Arboriculture provides a “find an arborist” link which can be used to locate local certified arborists for tree trimming and advice.
The American Society of Consulting Arborists provides a link to locate consulting arborists.  Consulting Arborists provide advice, but do not generally provide tree trimming services, and therefore may be more objective about a tree’s health.
Fees for services will vary.


International Society of Arboriculture: 

American Society of Consulting Arborists: