Updated July 10, 2013 - link at bottom
Preston looks at the very tallest trees on our planet and the people who seek them out, climb them and study them. This was a very engaging trip into a very unfamiliar territory. One amazing thing was that knowledge of the whereabouts of earth’s wooden giants is held by a very few individuals. The people on whom Preston reports range from Phd biologists to obsessives with no particular scientific background. He looks closely at tree-climbing methodologies (being a tree-climber himself) at the technologies extant that support such endeavors. I learned things here, and got a far greater sense of what is lost when land is clear cut. Well worthwhile, educational and engaging.
I first saw the article here, Lofty Aspirations
, in Smithsonian Magazine back in 2002. But when I searched for it on that site, it was a nogo. Thankfully it still lives on the author's site.