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THURSDAY

When Jordan Fisher Smith was a young hiker, he recalls in his new memoir Nature Noir: A Park Ranger’s Patrol in the Sierra, he tried in vain to keep two men from hacking away at a protected tree to stoke their “already overfed campfire.” But even later, when an older Smith was equipped with a ranger’s uniform, rule book, and sidearm, his efforts seemed futile: The area of the Sierra Nevadas that he spent 14 years safeguarding was itself slated to be flooded by a slow-moving dam project. “And so,” he writes, “you contented yourself with saving things, if not forever, for now.” Even on borrowed time, the area around the American River offers stories of all stripes, from the time Smith saved the life of a kidnapped baby tossed into a moving car, to the drudgery of park-ranger work (sweating over paperwork; sweating off 5 to 7 pounds during a stretch of on-duty days), to the occasional parachuting chicken. It’s usually compelling stuff, but the last chapter is particularly chilling: After heeding a doctor’s bad-in-hindsight advice (don’t sweat it, that tick probably wasn’t positive, and if so, you probably won’t catch anything) he suffers for years from Lyme disease, complete with fatigue and memory loss. Though he’s recovering, he essentially concludes that he’s shifted from park ranger to mine-shaft canary: “Environmentalists have been saying for years that as the land goes, so will we go,” he writes. “It should be no surprise to learn that rangers may be the first to know how true that really is.” Smith speaks at 7 p.m. Thursday, July 21, at Olsson’s Books and Records, 418 7th St. NW. Free. (202) 638-7610. (Joe Dempsey)