For conservationists in Vermont, “Wetland, Woodland, Wildland: a Guide to the Natural Communities of Vermont” is akin to the Bible. And with its plain language and detailed illustrations from Libby Davidson, it’s accessible to anyone interested in learning more about the natural world around them in the Green Mountain State.
Liz Thompson, an ecologist then working for the state Department of Fish and Wildlife, came across a guide to Missouri natural communities — recurring groups of plants and animals found in similar physical settings — at a conference in 1988. “For every natural community, there was a page long description and these beautiful black and white photos and I just sort of decided that we should copy it.”
Thompson and Eric Sorenson, a biologist with the department, did just that with a field guide published in 2000. The duo — joined by state lands ecologist Robert Zaino as the third author — released a new edition of the book last month.
VTDigger recently spoke to Thompson, Sorenson and Zaino about the new version and conservation efforts in Vermont. The interview has been edited for length and clarity.
VTDigger: What prompted you to originally write this book back in 2000?
Thompson: In 1988, I went to a conference … and there was a guide to the natural communities of Missouri. Their Department of Natural Resources has tons of money. So I saw this book and it was more … of a technical manual. But for every natural community, there was a page long description, and these beautiful black and white photos and I just sort of decided that we should copy it.
I began working on this myself, but soon after, Eric came on to the Natural Heritage Program as the community ecologist and so we immediately started to collaborate on it together. We hired a photographer to take black and white photographs because I thought that was the direction that we were going to go. But as time went on, we decided to provide illustrations … because we think we can convey more information with those and … color photography. So it morphed into more of a field guide rather than a technical document.
Sorenson: I think the underlying reason was that nature is really complicated … and if you can narrow it down to a set of natural community types that reflects what’s out there on the landscape, it’s easier for all of us to comprehend that complexity.
I think more traditional field guides are about trees, or plants, or birds … and there’s usually not much dispute about whether it’s a bluejay or chickadee. But natural communities are explaining the huge amount of variation we see across our 6 million acres in Vermont. And it’s a way to bring it down to now 97 types that explain that full variation.
Thompson: We felt also that it’s really important for people to use natural communities as a land management tool. And the only way to get people to grasp that or go with it, we felt, was to create a guide that would help people understand the concept and the natural communities.
The natural community concept was developed by The Nature Conservancy in the late 1970s and ’80s. The chief scientist … came up with this idea of a coarse filter approach to biological diversity: if you protect good examples of each natural community type throughout its range, you will also capture a lot of the native species.
VTDigger: In the introduction, you talk about a three-pronged approach to conservation. Could you explain that?
Zaino: When we think about all of the species that are here, and there’s estimates that there’s 20 to 30,000 different species in Vermont, we know almost nothing about most of them. And their natural habitat is somewhere in these 97 different communities.
But species don’t just persist in these single places. And so we have to think about giving them the space to move over time. And that means thinking about maintaining big chunks of forest, having connections between forests and (conserving) riparian areas for the species that live there. That’s kind of that landscape scale, thinking big.
Then within that, there’s places … where maybe there’s a more focused conservation need, because it’s a place driven by very particular factors. That helps build your confidence that you’re conserving many different species.
And then there’s some species where we can protect their habitat and it’s not enough. A good example is the softshell turtle that nests on these tiny little beaches — their natural communities — but these turtles are threatened by people trampling their nests, by predators. And if there weren’t people going out and making a concerted effort to protect those species, they wouldn’t persist here.
VTDigger: What are the main ways you have updated this book in the two decades since it first came out?
Thompson: We got Bob (Zaino). Bob’s contributions have been really important in improving the quality of work because he’s been working on this for 10 years now.
Zaino: So one of the things that’s been neat about the trajectory of this book is that I think it did really embed the concept of natural communities in conservation work and in people who are thinking about land management.
And so here at the Agency of Natural Resources and the Fish and Wildlife Department, Eric and I are both ecologists going out in the field, studying natural communities. Using that information, Eric is helping private landowners understand what they have. And I’ve been working on lands owned by the state, we use the natural communities (concept) to understand what’s on places like Camel’s Hump … to make good decisions to protect those different natural communities.
So I’ve been able to go out and try to figure out where these (communities) are all over the state. And then of course, you go out and you start looking at them, and you will find things that don’t quite fit the book. Then you say, well, how does that fit in?
There’s a bunch of stuff that doesn’t really fit what was in that first edition.
VTDigger: So you’re adding some new community types?
Sorenson: Part of this has been a fairly systematic approach to conducting inventories across the state, say of northern white cedar swamps or … all montane spruce fir forests and collecting data and analyzing that to see how they fall apart or fit together as types. So the differences in species composition and structure and soils, and elevation, all those kinds of things fit together.
And some communities fall out and we say, well, we have called that one type and now we’ve decided that it really should be two types. And those differences make the natural community classification more accurate and more useful both as a management planning tool and a conservation tool.
A good example that I think about is swamps, like hemlock swamp, we called it before. And now we’ve separated that into two types. One that is a basin hemlock swamp where it gets very little water from groundwater and one that gets a lot of groundwater discharge. They’re vastly different as far as two swamps can be in terms of species composition.
Thompson: And we added a new biophysical region.
Sorenson: Champlain Hills is the new one.
VTDigger: What’s a biophysical region?
Zaino: They’re areas that hang together because they have similar climate, similar topography, places where you tend to have similar geology. And all of those things lead to having similar natural communities. So I think most people can recognize that the Champlain Valley … is really different than the northern Green Mountains and that the northern Green Mountains are different (than) … Orange County in the northern Vermont Piedmont.
VTDigger: So what’s the process for deciding Champlain Hills should be its own biophysical region now?
Thompson: The U.S. Forest Service engaged us to to take a closer look at what they call land type associations in Vermont. Through that work and through looking at geology and soils in elevation and so forth, it became clear that the Champlain Hills, which had been considered part of the Champlain Valley before, is really quite different and has its own set of natural communities.
VTDigger: In the preface to the book, you write that the changing climate “distresses us and has caused us to change our thinking about conservation.” Can you talk more about that?
Sorenson: It’s huge for, not just the book, but for how we do conservation. Warming climate, changing weather patterns mean that species have to shift locations … and species have done that, over the past millennia as the climate has changed, but now it’s changing really rapidly.
And one of the things that’s changed dramatically in our landscape is how connected it is — or unconnected it is — because of roads and development and fragmentation, so it’s much more difficult for species to move. One of the things we need to consider in our conservation work now is how species will move in this fragmented landscape.
And related to natural communities, it made us be even more clear that what we view as a natural community now, a rich fen or northern hardwood forest, may not look like that in 100 or 200 years. This is a view of what they look like now and each species is going to shift on its own and (the communities) could be different in the future.
Thompson: Scientists talk about the idea of novel communities and that in the future, there’s going to be assemblages that we’ve never seen before. And we know from the Paleoecological records that … 1,000 years ago, things were really quite different and we didn’t have the same assemblages. This will be … true again as the climate changes.
But that doesn’t mean that it’s not important to recognize the natural communities that we have now. The species assemblages are a reflection of the underlying substrate, the geology, the bedrock, the soils and the landscape position, and that stuff is not going to change.
People talk about, well, why would you protect … a mountain spruce fir forest on a mountain top that’s not going to be there in 200 years. But something’s going to be there that’s interesting — something that reflects that extreme of climate … is going to be there and it will still be important. So in a sense, it’s a way of capturing the underlying physical environment.
Zaino: Climate change has shown us that the original idea that we could just conserve examples of all the natural communities is not going to be enough to keep species and to keep Vermont as a place where wildlife thrives and where plants thrive. But going to what Liz was saying, if we don’t keep all those different natural communities, we definitely won’t have that abundance of species in the future. Having that full diversity of the landscape is critical and natural communities are a way we can find those places now. And thinking about change raises
really tough questions, I think, for people who care about places.
How do we come to terms with it, that these places will change? To what extent do we try to keep species here because we value them? And to what extent do we recognize that things are going to leave Vermont and new species are going to come (which) makes for thoughtful conservation challenges, and there’s probably no right answers.
VTDigger: We’re already seeing climate change in Vermont. I’m curious if you have noticed any adaptations out in the field in response to this?
Sorenson: I don’t know if we have any documented evidence of that kind of thing here in Vermont. There are other places now that have species shifting upslope to cooler climates.
And there are examples of things that I think are visible here now, like south facing rocky outcrops that have scattered trees around the edge because it’s hot and dry. If you have a long drought in the middle of summer now, that’s enough to expand that rocky outcrop. Because it doesn’t take much to shift that setting to be a place where it can’t support trees.
Thompson: Going back a few years ago, I remember flying around with Ian Worley who was a pilot and an ecologist who helped us with some of this work early on, but I remember it was a really hot, dry summer. And there were just a lot of dead trees on those south and west facing knobs.
Sorenson: And that’s not a large scale change but it’s obvious in those small, super dry hot places.
Zaino: I think the other place we see it is by rivers where events like Tropical Storm Irene scoured the shores. We can’t link that directly to climate change but it’s the type of event that is going to be more frequent. And we see changes in communities, particularly with the spread of invasive species.
VTDigger: Can you each share a favorite natural community type?
Thompson: I love floodplain forests, especially silver maple-ostrich fern floodplain forests. I’m fond of saying whatever natural community I’m in at the moment is my favorite, but that’s not really true. I especially love floodplain forests when they’re dominated by silver maple, which is just a beautiful, graceful tree and understory ferns.
Zaino: I guess my favorite would be boreal calcareous cliffs. These are the communities that you can see at Lake Willoughby or Smuggler’s Notch, cold, wet cliffs that are rich in calcium, which is a really important plant nutrient. So when you have lots of calcium for plants, you get species that you won’t find most other places. Things like butterwort, which is this carnivorous plant that grows on the wet rock and it has these sticky leaves that trap insects. Or White Mountain saxifrage which has this rosette of leaves with little white dotted calcium crystals around the edge. Scientists are finding that those calcium crystals help it maximize the light coming in for photosynthesis so it has that little extra edge in that harsh environment.
And Vermont’s pretty cool in that we have lots of bedrock that’s rich in calcium compared to the surrounding states so we have lots of these species that you don’t see very much other places. And some people say, and I’d agree, that that gives us a special responsibility to protect these calcium rich cliffs.
Sorenson: I have two. Rich fens, which are small peatlands that get groundwater discharge. They have ancient, deep peat and a huge number of species in small areas — like 70, 80 species in a fen that might be a quarter of an acre.
And a contrasting one is limestone bluff cedar pine forest, which occurs almost entirely right next to the shore of Lake Champlain. I love limestone cliffs and … (the) gnarled old northern white cedars that grow on these dry windy sites right above the lake.
VTDigger: Conservation-wise, what do you think Vermont is doing well as a state and what areas could we improve on?
Sorenson: That’s sort of at the heart of what we’re all working on now. The Vermont Fish and Wildlife Department, they’ve supported Bob and I and doing all our work on this. But their mission is really — all of our mission is — the conservation of all species of plants and animals and their habitats for the people of Vermont. And in order to do that, we have to take this big view of what conservation is, and how to get to a solution. And it’s that mix of working on natural communities and landscape scale features. We are really lucky in Vermont that we still have the opportunity, because we have a really intact landscape, to bring that intact functional landscape into the future. So we’ve focused on natural communities as just one part of that. It’s all the other things too.
Vermont is 80% privately owned and that’s great. And we always think about how do you make conservation work for landowners so that they can make decisions to keep their land intact, healthy, because there are always economic pressures. And it’s sort of society’s obligation, I think, to help landowners with the stewardship of land and important places.
Thompson: Even though 80% is privately owned, a lot of that land has conservation easements on it for permanent protection. The state’s current use program is not permanent protection, but it is a really great program that keeps a lot of land in a natural or less natural state. A lot of the forest lands enrolled in it is managed for timber and in some of it is farmland, but it’s still keeping forest as forest.
Correction: This story initially quoted Thompson as saying that the current use program is “not keeping forest as forest.” Thompson actually credits the program for keeping forest as forest. The word “not” has been removed.
