Last year, the Confederated Tribes of Siletz Indians petitioned the Oregon State Marine Board to impose a motorized boat ban on the upper Siletz river in Lincoln County. The board is expected to issue a temporary rule at its meeting in early April, ahead of a series of public meetings.The tribe’s petition would ban motorized boats upriver from Jack Morgan Park, which is about six miles north of the town of Siletz. They say a ban would help prese…