Naked Man writes: "BTW, I've noticed the authorities have put up several new red CLOSED trail markers on the mountainside off JF3 or 4 (?) where dirtbikers have blazed yet another trail up the side of a mountian."
This practice was utilized by BLM after the Willow Fire, and distribution of red carsonite markers was made to key locals who assisted in the effort. However, BLM discontinued the practice after realizing that closure signs attract defiant dirt bikers. BLM now signs only the open routes, and so the signage effort you are seeing is not likely by BLM authority.
BLM has been frustrated in their attempts to maintain open route signage on JF3 and JF4, and that vandalism is likely contributing to trail proliferation.
Mojave