AT A WILDFLOWER TALK I attended in spring 2017, a lot of the audience questions after the expert finished her slides were ones like this: “Is such-and-such a Trillium native here,” or, “Have you ever seen (insert name of a particular fern) growing in the wild in this area?” We were all curious about the hyper-local version of what plants really are our natives.

Yes, we know the labels on various commercial nursery plants, like a coneflower, or lupine, or Coreopsis, may say “native,” but keen gardeners probably have figured out that that’s often used quite generically in marketing, perhaps implying U.S. native, or maybe regional native at best.

As I consciously add more natives to my garden, I wanted to learn how to get a little more precise than that. Who better at the time to ask for guidance than Elizabeth Farnsworth, Senior Research Ecologist for what was then called New England Wild Flower Society, now Native Plant Trust? No matter where you live, Elizabeth helped map out a strategy for learning more about your native flora—and talked about what native means at the moment, anyhow, and why it matters. An extensive list of go-to resources appears at the end of the transcript. I’ve also include screenshots from some of the leading tools with maps, using the native white pine as the example in each case (a collage of those, top of page).

Update: This interview is poignant for many plant lovers like myself, because Elizabeth died suddenly later in fall 2017; an appreciation is here.

Read along as you listen to the Sept. 18, 2017 edition of my public-radio show and podcast using the player below. You can subscribe to all future editions on iTunes or Stitcher (and browse my archive of podcasts here).

what’s native where you garden?

a q&a with elizabeth farnsworth

Q. You’ve worked at the Society since 1999, I think. Is that right?

A. That’s right. Let’s not do the math, though. [Laughter.]

Q. Okay, sorry about that. And you’ve been working with native plants probably longer than that, to save rare plants, to conduct research on plant ecology and evolution, even responses to climate change. In your time in the field, I expect the word “native” has evolved in its definition, hasn’t it?

A. Yes. It definitely has. It has long, as a definition, puzzled scientists. We’ve been poring over this definition probably for 200 years or more. There’s a very, very rich scholarship that goes back quite a long way, in terms of trying to identify what would be considered a native species, versus one that’s introduced.

I think over time we’ve made some strides in terms of developing something of a coherent definition. It is increasingly based on the science, on the genetics—on understanding how long plants have been in a place for a period of time, and lots of other evidence.

It still continues to be a thorny issue, of course, because plants are constantly moving around. They do not respect political boundaries, and we’re trying to train them that way, but they simply don’t. They move around by virtue of both humans moving them around, but also by natural processes, their own ability to disperse and establish in new places. So we’re constantly grappling with this. This is not a static definition, because the species themselves are not static.

Q. So we should probably do something you sort of just hinted at. There are some of our “wildflowers,” speaking of a generic word—naturalized plants, maybe plants that were brought over hundreds of years ago by settlers, and they look like they’ve been here forever and they’re super-familiar throughout our whole lifetimes and long before, but they’re not technically native. So those are those naturalized plants.

A. Right. They’re plants that have basically escaped from cultivation. We brought them over, or potentially First Nations people were bringing them from place to place for their medicinal value, their food value, their wildlife value, etc. Humans have been moving plants around for a very, very long time.

Q. Okay. Before we figure out what exactly is a native: besides satisfying my insatiable curiosity, why does it matter to know what the specific natives to a particular area are? What would be some of the reasons besides curiosity that it would be good to know?

A. Well, a lot of native plants have established themselves—established ecological relationships with other organisms, such as their pollinators, the birds and other animals that feed upon them. They provide foundational ecosystem services, in terms of flood control and erosion protection and lots of the other services that benefit us as well as other organisms.

Some of these native species are what we consider to be foundation species. These are species such as hemlocks and mangroves, for example, that literally form the basis of whole ecosystems, of the habitats, on which other organisms depend.

Native species do provide these essential services. They are an integral part. They’ve evolved here for a very long time, and form part of a very diverse network of organisms. From the perspective of gardeners, I think it’s also important to reframe the conversation in some ways, and not get entangled in the weeds, so to speak, of native definitions. Although, we can certainly return to what scientists refer to as native.

It’s important to understand the plants of the relatively natural areas around you, to observe them over time, and to notice those interactions that they have with other organisms.

Q. So is that sort of a habitat style of thinking, then? That I’m thinking, like you said, there are these foundation species and then there is the community around them?

A. Right. Scientists and botanists, natural historians, have developed definitions of what we call natural community types. These are types of habitat in which we can actually pretty reliably predict what will be the dominant plant species present, because they have adapted to these habitats.

Consider a salt marsh. Salt marshes go all up and down the East and West coasts of the United States, and we can pretty much predict, “Well, I’m standing in salt marsh because there are these cordgrasses and other species that have been recorded from these areas reliably for many, many years.” We have a very rich history of botanical collection. We understand what species are likely to occur in those habitats, and we’ll define them.

If we find a species from a particular habitat type that we know is likely to occur there in a completely different habitat—so think of finding a pitcher plant, one of our carnivorous plants, that we know only typically grows in nutrient-poor bogs. If we find that growing in a puddle in New York City, chances are it’s probably not native there. [Laughter.]

Q. [Laughter.] Okay. So that’s how I can tell.

A. That’s one way.

Q. Okay, good. I’m glad I know that. [Laughter.] Again, the extremes can be from the nursery tag that I mentioned in the introduction, where they have some little icon, or it says “native,” or whatever, but you know that could mean it’s an American native. It can mean it’s a native to the prairie or whatever, not to where I garden or where someone else gardens.

Then there’s the other extreme in horticulture, where some of the wholesalers who got custom orders to propagate something for, say, a landscape designer may order 500 of something, but he wants the local ecotype—I think that’s what you call it—but he wants the genetics to be not just the “fill in the blank” whatever it is. He wants the local genetics. He wants it propagated from the exact local population. It goes from like loosey-goosey to like, wow, down to the chromosomal level, right?

A. Right. That’s something that we pay attention to ourselves at New England Wild Flower Society, and our partners working with programs such as the Seeds of Success program, where we are trying to restore habitats, for example, that were destroyed by Hurricane Sandy. When we collect seed to restore those habitats, propagate those plants, we want to collect seeds from the areas close to where those areas are that we seek to restore.

The assumption there is that, in fact, those plants are probably reasonably well adapted to the areas in which they were formerly growing. It doesn’t necessarily make a lot of sense to introduce a particular species from Maine to Maryland in order to reforest areas or to revegetate areas, because we can pretty well document that species from very different latitudes are probably not going to perform as well in much different latitudes.

Q. Let’s get sleuthing, then. Let’s talk about some sort of tools and tactics. I think I mentioned to you when we’ve corresponded before this, that I’m a birder and I’m used to looking at range maps for species. Sometimes, I’ll see a bird and I don’t know what it is and I think, “Hmm, could that be such-and-such?” and one thing I always do is I look at the map.

A. Right.

Q. Is it something that might pass here at migration time, or be here in breeding season, or whatever? With plants recently, as my interest in insect interactions with plants has grown keener the last few years especially, I sort of started trying to do the same thing with plants and looking for a set of maps. I found lots of different things that I’ve been using, but I’m wondering where you’d send me. And not just for those living in the Northeast—but where does the hunt begin?

A. There are a number of resources. Going nationwide and also into Canada and beyond, I think botanists have been trying to create databases which help people understand the regional, national, and even continental distributions of these plants. Of course, I’m going to mention first …

Q. Let me guess; let me just guess.

A. Go Botany.

Q. Go Botany, baby. Go Botany. [Laughter.]

A. Right. Go Botany, baby, from New England Wild Flower Society. We have done an extensive amount of research to understand which plants are native to particular counties, particular states, within the region. This is based on a whole bunch of different lines of evidence, and I can go into those in a bit. Go Botany is a great go-to for anyone in the six New England states.

There is also Calflora, for any of your listeners who are listening from California. I’m going for the areas of the country that have some of the most diverse plants on the planet. So Calflora is also a great repository of maps and information on what they consider the plants are that are native, and possibly more important, potentially invasive in particular areas of the state. [Below, the map for Pinus monticola, the Western white pine, from Calflora database.]

There’s also nationally the Native Plant Information Network. This is based out of the Lady Bird Johnson Wild Flower Center …

Q. Oh, yes; of course.

A. … in Texas, and you can get an alphabetized list of all of the plants. They have information on more than 8,500 species of plants nationwide, on which they have data. These are primarily native plants, but you can narrow down your search to a particular area. If you are in Illinois, you can search on what are the native plants that have been recorded in this database for Illinois.

There are also state-level atlases, which are incredibly useful because generally botanists have been on the ground dedicated, searching for, and documenting plant populations. An example of this is in your very own state, the New York Flora Atlas …

Q. Yes.

A. … where you can search for a list of plants that have been recorded for a particular New York county, and you can restrict that list then to list what are considered the native plants, or conversely the non-native plants for that county.

Q.  Right, because when a flora, when a survey is done of what’s there—as you say, it’s botanists on the ground, seeing what’s around. They’re counting all that they’re looking at to see the diversity, not just the one or the other.  So you can then sort, and say, “I just want to see the natives.”

A. Exactly. These are the dedicated experts who are really want to understand what’s present, native, not native on the landscape.

Q. Okay.

A. If any of your listeners are from Canada, there’s the Vascan searchable online atlas of the vascular plants of Canada. It shows you a map along with the native or non-native status of plants at the provincial level. It allows you actually to create a province-based checklist. [Above, sample Vascan map for Eastern white pine, Pinus strobus.]

There’s also the Biota of North America Program, which again is another North American program that has maps of species. You can map them actually to county, for each state. You can search on a particular species and understand what its distribution is, native and non-native. They are beginning to develop tools that allow you to create a checklist for your own county, pretty much anywhere where you are.

Q. Now, is that the one that you refer to in the Go Botany from New England Wild Flower Society?

A. Yes. We share the data, so the Biota of North America Program, BONAP did share data with us on regional distributions of plant species. We have updated those data for New England based on the “Flora Novae Angliae,” and all of the different floras that have been created for the six New England states. What’s represented on Go Botany we are very grateful to BONAP for providing us with the baseline data, and we’ve tweaked those and updated them to reflect county status. [Below, sample BONAP map for Eastern white pine, Pinus strobus.]

Q. I was recently turned on to that plant atlas, the New York Plant Atlas one, by a botanist friend, and it’s great. It’s so great. It’s wonderful when I then compare them to the BONAP maps. Sometimes, when I see a plant and I think I know what genus it’s in—I  think it’s a whatever, but I’m not sure which one—on the BONAP you can just go by genus, and you can see all the species within it, and what their range is, all together like miniature maps gridded out, and get a sense. “Hey, look. It’s definitely not those three, because those are only in the West,” or whatever. Do you know what I mean? [Below, from the BONAP database, the thumbnail-sized maps of possible Clethra species as an example.]

A. Right.

Q. Again, I don’t have your expertise so I’m doing this in a lot more of an amateurish way, but the maps are so … We all know about maps, and they’re so visual. It’s not just a lot of Latin words.

A. Right.

Q. It’s like, “Oh, yes. It could be these five,” you know?

A. And it’s so wonderful all of these different kinds of web tools, right?

Q. Yes.

A. And what you want to be actually able to do is to visit a number of different sites, so NatureServe Explorer is yet another site, or the USDA Plants Database. There may be a little bit of disagreement among these sites, so what you want you to do is cross-reference. [Below, Pinus strobus map from USDA plants database.]

In the end, your local floras are going to be some of your most current sources of information.

Let’s not just stay online, but to remember that hard-copy books, field guides, are also being produced that at least for this year, and the next several years, will represent some of the most up-to-date information that you can get, and you can carry those right into the field with you.

There are also actually websites. I found one for the Rocky Mountains, a website that gives you a whole list of field guides that are relevant to the Intermountain West.

Q. Going back to my bird analogy, because everytime I feel like I go on an adventure, one of my first nature adventures was learning about birds, so I always try to use the skills that I’ve gleaned from that experience. And so one of the things is that sometimes the local bird club, if you have a really good bird club in your area, they have a checklist on their website of local species.

A. Right.

Q. And dot, dot, dot, Margaret thinks, “Ah-ha! Maybe the local preserve, or the local wild flower society, or the county whatever, some nonprofit, might also have such a list.” That would be another thing to look for. I mean obviously you are one of the premier ones, the New England Wild Flower Society, place that has those types of resources.

A. Absolutely. There are organizations such as, for example, the New England Botanical Club, whose members go out and do field forays and field trips to various localities all over New England. They will come up with a plant list from a particular field trip, and most that right on their website. If you go out to the same or a similar type of site, you might keep an eye out for some of those interesting plants that they saw.

Q. In your work, do you still have field guides in your life, Elizabeth Farnsworth?

A. Of course.

Q. Do you still have old style ones—because I’m a field-guide freak. I have cupboards full of them. I love field guides, but you use them?

A. Absolutely. In fact, I have whole bookshelves full of field guides that I go to. Most recently, I’ve been called upon to go to a number of insect field guides.

Q. Me, too.

A. Working at Nasami Farm, which is our native plant nursery in Whately, Massachusetts, we see all sorts of crazy caterpillars out there. And having published a book on the ants of New England—my own field guide, co-authored, to the ants of New England—I am constantly called upon by people from near and far to say, “Okay, here’s a photograph. What’s this crazy insect?” And of course, I will go to David Wagner’s amazing field guide to the caterpillars.

Q. Oh, the best.

A. He’s an amazing professor at University of Connecticut, and of course I have his encyclopedic field guide right there on my shelf. Sometimes, that can be so much more efficient to leaf through an actual book—I’m going to sound like a Luddite here—than trying to tap into a website where you’re trying to narrow things down.

Q. Well, no. I’m crazy for the Dave Wagner book. I guess the Western volume is coming some day, too.

A. Yes, it is.

Q. He’s working on that, and Arthur Evan’s book of beetles.

A. Right. Yep.

Q. And I have the Peterson Guide to Moths, from Seabrooke Leckie and David Beadle, and the butterflies, and the this, and the … wow.

A. Yes.

Q. I just, as you said, paging through … There are often sometimes, at outdoor stores, maybe where you would get camping gear, or even fitness clothes, sometimes they’ll have local little guidebooks, little field guides to your local area.

A. Sure.

Q. And sometimes they’re cute and they’re not fancy, but they’re so good.

A. Right.

Q. They’re so good to have.

A. They are. Things like “The Fern Finder,” for example, which is a tiny little credit-card-sized flip book that enables you to identify most of the important true ferns in the Northeast. It just doesn’t get better than that. How much more economical than … it’s a quarter the size of your cell phone, even. You can just put that into your backpack and go on your merry way.

Q. “The Fern Finder.”

A. Yeah.

Q. We have a couple of, two or three, minutes left, and I just am curious: What have you been up to this summer? What have you been discovering, or rediscovering, or what have you been working on?

A. I have become our rare-plant seed curator at Nasami Farm. We have launched … well, we have been the region’s major repository of seeds for both rare and some common plants. I mentioned earlier our Seeds of Success program, with respect to provenance, but we have hundreds of volunteers out on the New England landscape collecting seeds of rare plant species for our seed bank.

Literally, I have processed over 2.3 million seeds coming in as collections over the last several years, and we already have more than 70 collections coming in from volunteers this summer, this field season. I’ve been working with a fabulous bunch of dedicated volunteers to clean the seeds, to count them, to make sure they’re in good shape, before we package them up for permanent storage at our seed vault.

And New England Wild Flower Society is involved, or is spearheading actually, a major effort to become the region’s premier seed bank. We have matching grant from the Iselin Foundation for half a million dollars to build a whole new seed bank facility at Garden in the Woods, so we’ve been really ramping up our seed collections. This is one bet hedging strategy against climate change.

Q. Yes.

A. It’s one of the many-pronged ways in which we’re conserving plants, but it’s been a fabulous project. It’s fascinating for me as a scientist to actually see the seeds of all these rare plants with which I’m very familiar with on the landscape. But to actually see their incredible seeds, it’s…

Q. Very exciting. And maybe you can make some changes in some of those maps someday with some of those seeds.

A. Absolutely.

Q. Where things are fading away, maybe they’ll get a little reinvigoration with some of those.

A. Yes, and we’ve actually been involved in a project at Cadillac Mountain, for example, at Acadia National Park in Maine, to revegetate that denuded summit with some seeds of plants that we collected from there. We grew them up and we’ve replanted them out this summer, in hopes of revegetating that area.

Q. Well, thank you so much, as ever. I just feel like you’ve got me … I’m going to really go down the rabbit hole.

A. Always happy to help.

databases for identifying regional native plants

IN GENERAL, says Elizabeth Farnsworth, there are botanists in all 50 states and around the world assembling information on the plants of their regions. If interactive online website apps are not available (that’s a screenshot from the homepage of my state’s New York Flora Atlas, above), you can instead search to find field guides that have been published. Try Googling the geographic area of your interest, and the word “flora,” such as “Rocky Mountain flora” or “flora New Jersey.” Any local preserve or park may have lists, targeted field-guide recommendations, and other advice. As a start, some potential resources to tap into:

• Go Botany (New England regional), from the New England Wild Flower Society
• Native Plant Finder from National Wildlife Federation, University of Delaware and U.S. Forest Service (searchable by Zip Code; launched 2018).
• Atlas of the Flora of New England by Ray Angelo and David Boufford of Harvard. Doesn’t specify native, but does mention if the species’ origin from other countries/continents is known.
• Calflora (California), of native and non-native plants, including the ability to search by plant name or by location–so for instance to explore the plants of a park, or other area you might be visiting.
• Native Plant Information Network (National, Ladybird Johnson Wildflower Garden): Get an alphabetized list of all the plants (8,593 species) on which they have data, then narrow your search to a particular state.
• New York Flora Atlas: search for a list of plants recorded for a particular NY county. You can then restrict that list to native plants or non-native plants. For other states try starting at…
• …a list of state wildflower societies, from American Horticultural Society. The state societies will probably provide a link to the state flora database on their websites.
• Vascan, a searchable online atlas of the vascular plants of Canada, will show a map along with nativity status, and allow you to create a province-based checklist.
• The Biota of North America Program (BONAP) allows you to map species to county, for each state, and  search on a particular species and understand what its distribution is, native and non-native. Coming: tools that allow you to create a checklist for your own county.
• The USDA Plant database, including maps and the ability to search by state, for example.
• Missouri Botanical Garden: The Missouri Botanical Garden and more than 30 U.S. and Canadian institutions are collaborating on a printed and computerized inventory of the 21,000 species of plants of North America north of Mexico. Dr. George Yatskievych oversees the program and is director of the Flora of Missouri project. World project aiming for completion by 2020. Work to date is at the Flora of North America website, and will be published in print as well.
• You can also use MIssouri Botanical Garden’s Plant Finder, which specifies native range in the results of each plant description (but doesn’t include maps).
• NatureServe Explorer: Searchable database on 70,000 plant, animal, and fungi species, updated in 2016.

more from elizabeth farnsworth

• our previous interview about native plants
• the Native Plant Trust website
• Go Botany, the searchable plant database for New England

prefer the podcast version of the show?

MY WEEKLY public-radio show, rated a “top-5 garden podcast” by “The Guardian” newspaper in the UK, began its seventh year in March 2016. In 2016, the show won three silver medals for excellence from the Garden Writers Association. It’s produced at Robin Hood Radio, the smallest NPR station in the nation. Listen locally in the Hudson Valley (NY)-Berkshires (MA)-Litchfield Hills (CT) Mondays at 8:30 AM Eastern, rerun at 8:30 Saturdays. Or play the Sept. 18, 2017 show using the player above. You can subscribe to all future editions on iTunes or Stitcher (and browse my archive of podcasts here).

(Photo of Elizabeth Farnsworth by Nancy Cohen.)