Try offering the property owner some form of bargain to access their land. For example - offer to hunt or trap ground squirrels for the property owner. This personally worked for us down in socal at a disclosed DH trail. The drop-off point of the shuttle is technically on a "private drive," meaning the county does not maintain several hundred yards of paved road. When a disgruntled property owner tried to shut down a day of shuttle runs for "trespassing," I ask him if he had a ground squirrel problem. He replied, "everyone does around here" in a surprised tone. He further declined my offer to shoot his squirrels and ended up carrying on a pleasant conversation after that. We assured him that we respect the community and continued on with runs. Situation dissolved. Good read though and good luck with further trail access.