Air Date: Week of July 18, 1997

Most of us walk through the woods and see trees. But for ecologist and author Tom Wessel, a stroll through the forest is an historical journey; one that tells the story of fires, logging, settlements and storms. Producer Nina Keck recently spent an afternoon with Wessel and learned some ways to read the story of a forest. Tom Wessels'book "Reading the Forested Landscape: A Natural History of New England" is published by Countryman Press.

Transcript

CURWOOD: It's Living on Earth. I'm Steve Curwood. Most of us walk through the woods and see -- well, trees. But for ecologist and author Tom Wessel, a stroll through the forest is an historical journey. One that tells a story of fire, logging, settlement, or storms. His new book is called Reading the Forested Landscape: A Natural History of New England. Producer Nina Keck recently spent an afternoon with Tom Wessel.

(Bird song)

KECK: I met Tom Wessel at the entrance to New Hampshire's Wontasticat State Forest. Within minutes of shaking hands, he points to the hillside above us and begins describing what he sees.

WESSEL: You know, it's really neat to be out at this time of year, because you can see the different colors of green. The broad-leafed trees, which are just leafing out, are sort of a very light yellow green. And then sticking up through them and quite a bit higher are the pines, which are much darker. And that real difference in size, looking at these very tall pines scattered opening through this lower canopy, is telling me at last that something dramatic's happened on that mountainside over there. There's been some major disturbance, which has left these much older, bigger pines, but taken out many, many trees. I think we'll have to get in there and look around to figure out what happened.

(Footfalls)

KECK: Tom Wessel is director of the Environmental Biology Program at Antioch New England Graduate School in Keane, New Hampshire. He's a forest ecologist with a bushy beard and a warm smile. He says it was his students who convinced him to write the book. For almost 20 years he's been trekking through the underbrush and along winding trails, teaching people how to interpret the history of woodlands.

(Footfalls)

KECK: When you talk about reading a forest, it's kind of an interesting way to think about it. What exactly do you mean?

WESSEL: Well, I mean reading it the way you'd read a history book, although it's even more maybe like reading a mystery novel, I think. In my book I tell you about it being similar to being, to reading Sherlock Holmes, because you see that possibly something's happened to a forest. And then you start looking for the clues to try to figure out what has happened there.

(Footfalls)

KECK: Professor Wessel begins to unravel the puzzle of this place as we work our way up the hill. He points out various trees and stumps and explains that this forest was either logged, burned by a very hot fire, or hit by a hurricane or other strong wind storm.

WESSEL: This is a good place to stop because now we're starting to get some good clues here. If you look up here we see some huge white pines. Those trees have to be, you know, 3 feet in diameter or more.

KECK: Those are big.

WESSEL: Oh yeah.

KECK: How old would you say those are?

WESSEL: Well, these trees are well over 100 years of age. And actually these are small for the way white pine used to be around here. We used to have white pine that could get up to 8-foot diameters and 230 feet in height. These were giant trees that are similar to those found out in the Pacific Northwest. We don't have any more like that in New England because they're all clear-cut. But those trees, those really big ones, would have been about 400 years. These are probably 100, 150 years. And then if we look around us, most of the other trees are quite small and all about the same age. And what becomes noticeable is we're missing trees of sort of intermediate size. And we'd have to start to think about, well, what would probably take out medium-sized trees? Probably wouldn't be a wind event. The trees most liable to go down in a strong wind would be the really big trees that are left here. So we can probably already start removing a blow-down or a hurricane as the factor here. We sort of have to start looking maybe toward fire or logging possibly as what has happened on this slope.

(Footfalls)

KECK: Tom Wessel points to another important clue. Several red maples and white birch with more than one trunk. He says multiple trunk trees were either cut and the stump then sprouted, or they were heat-killed by a fire and the root system survived. So, how do you decide which it was? Well, if it was a fire, the author says, we'll find telltale scars at the bottom of the trees.

WESSEL: Oh, look at this. Right over here, there's a white oak and a red oak next to it. Both of them have scars, we can see those nice triangular-shaped wounds at the very base of the tree. And on both trees those wounds are on the uphill side. And that's really good, because when you find uphill basal scars like that, it's a sure sign of fire.

(Footfalls)

KECK: Dry sticks and leaves roll downward, and gather on the uphill sides of trees. During a fire, those piles of litter burn longer, and leave definite scars on the tree trunks.

WESSEL: So this is quite good. We're really seeing here the classic signs of fire.

KECK: It's not always so easy to figure out what happened. Professor Wessel says sometimes so many things have altered a landscape that it's hard to pinpoint one particular event. But even without the author to guide you, Tom Wessel's book makes doing your own sleuthing fairly easy. Each chapter begins with a detailed etching of a particular landscape, and those drawings are packed with clues. I found myself constantly flipping back and forth between the pictures and the text, trying to decode the signs of fire, agriculture, and disease in the forest before they were completely explained.

WESSEL: Most of us may know piecemeal fragments of the woods. We might know how to identify individual trees or wildflowers or birds. Or maybe we don't even know that and just enjoy the woods' beauty. But people really haven't, I don't think, learned generally to see things in an integrated whole.

KECK: The Vermont author says his readers often tell him that their experience of the woods changes dramatically as they learn to see patterns in the landscape.

WESSEL: Most people I find get really excited, because all of a sudden they see that the woods has history. It has stories that you can literally read. And that process becomes actually a dialogue. You go out and you start noticing changes in forest composition, say what happened here? You'll ask questions and the forest answers back. It provides the clues. You really all of a sudden start having a dialogue with your landscape.

KECK: In his book, Tom Wessel writes about New England. But he says the techniques he describes can be used anywhere. And he's already thinking about writing a second book on the forests of the southern Rockies. For Living on Earth, I'm Nina Keck.