And now tonight's Brief But Spectacular explores old growth trees and the natural history of Wisconsin's Northwoods.Author and naturalist John Bates takes us there. He's worked in the area for more than 30 yearshelping people understand the diversity and the beauty of nature and our place within it.Bates' most recent book is titled Our Living Ancestors.My interest in old growth took off in, oh, about 2003.I'd been walking in older forests, and found that they were quite rare and wondered why.Why did we cut so many down? They're a filter for air. They're a storage of carbon. They provide shade to our streams.I felt humility walking into these sites in a place where trees are 400 or 500 years old.I found myself feeling a deep gratitude that these trees were resilient enough to still be here.My job, as a naturalist, is to help people gain environmental literacy,so that they have a deeper understanding of place based on this enriched understanding of where they are.If you're standing under an old white pine here in Wisconsin that's 400 or 500 years old,you are standing underneath a tree that Native Americans had stood under.The trees are living tissue. They're not hardened amber. They're not footprints.They're not stories people have told with all the biases that we have as human beings. They're travelers through time.