Tree work on massive oak

+1 (510) 715-1917. Give Doug a call. He is a licensed arborist and we and our neighbors have used him regularly for various trees small abs large. 

We used Ponderosa Tree Services for our oak tree. They came out in a few days, gave quote, and then due to our urgent need, came out and did work to meet our schedule.

Whoever you choose, you should get them to come out sooner rather than later to do the work. Oakland Fire Department goes around in May-ish to inspect homes in the hills for fire safety, and when they notify homeowners that they have to trim trees back, there will be a rush of calls to all the local tree shops. We weren't on top if it, waited until late June and didn't know about how busy the tree guys get, and two places declined to even come out to do quotes.

Elite Tree service. I used them last year for major work on my very large Live Oak and this year on a neighbor’s Chinese Elm that was grown over my roof. Matthew usually does the estimates and he is great. Much less expensive (and no superior attitude I got from B&L). Very knowledgeable about all trees and is happy to work with neighbors. 
510-523-9399

I have used Brende and Lamb for years for our huge oaks, but this year they were booked out for many months in advance (I guess we were all stuck at home looking out the window and realizing "I really need to get the trees trimmed").  I turned to Matt Bowman at Complete Tree Care, and he his crew did a beautiful job (and charged less than Brende and Lamb).  His number is 510-883-1748.  

We’ve used Mark Dill with Foresttree company for many projects, including trimming a giant sequoia in our backyard. They’re great!!

Big Chief has been great for us in Berkeley.