Tree doctor needed

Hello,
My street has some quite old trees on it.
Last year a Jacaranda tree died.
The bark at the base started to turn brown and flaked off.
This year a tree on the other side of the street is starting to exhibit the same symptoms.
Right now the tree seems healthy but I want to nip the problem in the bud.
Chapala tree service is unable to help.
Has anyone had any good experiences with someone knowledgeable about tree diseases?
Thanks in advance for your help.

Franciso ‭(333) 452-9843‬. Ajijic tree service.

Thanks, I'll give him a call.
I thought maybe he just does pruning but I'll ask.