[Ol' Dan Tucker]

You need a permit in LA to trim trees?

You need a permit to trim city-owned trees, yes.

The sole exception is if the trees are intruding over your property line. Then, you may trim to your property line.

[Twotone]

Actually, a lot of cities are instituting rules for tree pruning & removal. Even on PRIVATE property. The city I gladly left had done that. You had to get a permit to trim your own damn trees!