Sign up for the daily CJR newsletter . America’s national parks are facing unprecedented political and environmental challenges. Over the past fourteen months, the Trump administration has systematically dismantled protections for protected lands, despite record-high visitation. Much of what we understand about those efforts is due to the excellent and rigorous reporting of Ashley Harrell , the national parks bureau chief for SFGate , and her team .  It appears their coverage has touched a nerve. Last week, Harrell reported that, according to internal communications she reviewed and interviews with a number of sources, the Department of the Interior has effectively blacklisted SFGate . “We have received direction to not respond in any way to any inquiries received no matter the topic from SFGate ,” an employee shared with her.…