Great adventures beckon to all of us."" Elder woodsman Sigurd Olson, who died early this year, had a knack of striking the common chord--so it is fitting that these last, brief pieces, rooted in the Quantico-Superior country but ranging far beyond, deal with the common stock of outdoor experiences. Among the Sequoias, Olson is moved, as John Muir was, ""to realize that they were mature long before the continent was discovered."" On the prairie, he thinks of the vanished buffalo; as a fisherman, he welcomes the return of the sturgeon. He calls up night sounds--a thunderstorm (""phenomenal""), animal prowlers, ""the whisper of wings overhead,"" a harmonica or banjo (""all music is more haunting then""). He catalogues ""little rivers I have known"" and rocks he's collected (""each having a story to tell""). He takes stock of trees--the cedar, the spruce, the hemlock. (On a Wisconsin farm, Olson and a grandson search out five hemlocks--each, a prize.) He remembers friends of the trail; salutes maverick naturalists; recounts, with resignation, scourges he's lived through (tent caterpillars, the Dutch elm disease). ""All catastrophes disappear and are forgotten over the years, for that is the way of life."" Reaffirmations, plainly put--for those who also responded to Reflections from the North Country and its predecessors.