Whether he's racing up a rope, leaping from limb to limb or skillfully swinging a saw, Mark Chisholm has spent his life in trees. We talk the secret to competitive tree climbing, life as an arborist and the best trees in the world. Then, it's a special sporty Top 5.Mark Chisholm: 2:00John Shull: 26:15Top 5 Obscure Sports: 34:19Contact the ShowInstagramMark Chisholm WebsiteMark Chisholm InstagramMark Chisholm Twitter Learn more about your ad choices. Visit megaphone.fm/adchoices