Beringian Botany

Field Botany for the Future: learning botanical field work in Alaska

by Ingrid Jordon-Thaden

Imagine your favorite spot in the woods. The smells, the sounds, the visual appeal. You have come to this spot repeatedly, and you see it when you close your eyes. Your mind goes to it when times are down. You are relaxed by the thought of it looking the same as it has now for all the years you remember it. Now, imagine what it would look like if the weather there changed so drastically, that the plants and animals you remember there can no longer survive. The oak trees? Gone. The wet little stream with tiny plants? Gone. Those little orchids that pop up each season? Gone. The sound of singing frogs in the little pond? Gone. The scat you often identified to be either fox or coyote? Gone. This is what today’s students’ great-grandchildren will be faced with. Their view of your favorite spot in the woods will be drastically different from what it is today. This disaster is not far off, and it is almost certain if we continue our current trajectory of atmospheric alteration of our biosphere.

So, what can we do? What do today’s students want to do? They want to know how they can help. They are hungry to have their “boots on the ground” to stop this habitat loss in its tracks. As educators and scientists, it is our responsibility to provide them with the opportunities to gain the skills needed to recognize a habitat in peril, how to recognize a habitat in good health, and how to properly document its progress. This, this is what field botany does for our future.

The Department of Botany has been incredibly lucky over the years to have enormous endowments given to our mission of teaching and studying botany. One donor created an endowment that is directly focused on giving students the real, hands-on botanical field experience. This endowment, named Alexander Von Humboldt Endowment for Field Botany, is held at the University of Wisconsin Foundation (fund number 132160002), provides partial funding for students at University of Wisconsin-Madison to support student opportunities for botanical field experiences where they can learn field botany anywhere in the world. It simply requires that an instructor from the Department of Botany create and operate the course.

In the fall of 2019, I was inspired to create a course which led a group of students to Alaska. Why Alaska? Well, let me tell you a little about it. The Arctic, as we have heard, is under severe stress and environmental change due to climate change. Not only for the animals that we often hear about — polar bears, musk ox and the like — but also for the plants which hold the Arctic tundra and permafrost together. These plants on climate’s “edge” are predicted to be the first in line for extinction when climate change has reached its certain climax. In addition, alpine communities in mountains all over the world are in great peril. I have been a botanist now since 1995 and I have been drawn to these fragile communities. My PhD work focused on a species-rich genus of mustards (Draba, Brassicaceae), which has about 400 different species almost exclusively found in alpine and Arctic habitats. As you might imagine, Draba also has many plant “neighbors” in these communities, and I have become familiar with all of their distributions (ranges in which they grow) and their general biology. I have been intrigued by their historical migration. How did they get here up on the mountains and in the Arctic? What drove them to these “fragile” ecosystems in the first place? How did they survive the Ice Ages? How did the Ice Ages affect them? The Arctic and alpine communities of this earth are considered a type of desert. This means they receive a small amount of annual rain fall (~10-40 cm), and there is a long season where the water is unavailable while it is frozen. These plants have adapted and done so very quickly. Research shows that these plants have adapted to these types of climates in as little as 3 million years or less!

So, if they are so “fast” at adaption, could they possibly also be able to adapt to human-driven climate changes? Well, the answer is a resounding ‘No’. The rate of change from anthropomorphic-induced processes is orders of magnitude faster than the time it takes for evolutionary adaptation of morphology characters in plants and animals. The Arctic and alpine communities are likely to collapse due to increased heat, and increased rainfall. These plants have adapted to a very specific amount of rainfall and available for only certain times of the year. Essentially, our arctic and alpine communities are going to cook and drown.

I know that is a sobering thought. I think about it every day, and so do the students. The students that answered my call for participation in a special course designed to study the history of plant movements during the last period of accelerated climate change, the Last Glacial Maximum (LGM) of the Ice Ages, were also very keen on knowing how they can make a dent in such an insurmountable problem. What can field botany do to help these communities? Are we talking about building little roofs and air conditioners over mountain tops to protect them from getting too hot and wet? No, unfortunately we are not. We are talking about trying to determine how the health of a population of plants can be altered. How fast does a population of plants respond to climate change? What does a population need in order to stay healthy? What can we do to help a population stay healthy or return to an improved health? How do we even define a healthy population in the tundra?

Ok, ok, but how? How can we study plants’ historical movements and population health? More specifically, how do we determine if a population is genetically healthy? We do this by studying their lineages and family trees! By studying historic movements of plants due to glaciation cycles in particular, we learn more and more about how these populations survived and rejuvenated during contractions and expansions of their ranges in a relatively short period of time (100s to 1,000s of years). When we have a better understanding of the changes in population dynamics during this relatively short time, then we can extrapolate this to the current situation of climate change. We are working at the intersection between the fields of population genetics and phylogeography. Let me further explain, with using Alaska as an example.

During the LGM, large ice sheets covered most of the continent of North America, as well as glaciers all over the world in areas of high altitude. When the glaciers expanded and retreated in the alpine communities, the plants simply went up and down the mountains, adjusting their footing to stay within their desired temperature and moisture regime. This type of movement of altitude change is a “simple” population dynamic process, but also resulted in alpine plants having all sorts of genetic specializations. For example, polyploidy (genome doubling), apomixis (seed formation without sex), extensive vegetative reproduction, tough seed coats, and very extensive root systems. This process is one of many ways to create new species. The animals move the seeds up and down, roots get broken off with water washing and re-root in the right spot, and newly adapted seedlings from polyploidy find they adapt to a spot better than their parents would alone. As a result, alpine communities between mountain peaks and even mountain ranges have extreme resiliency to glaciation cycles as long as the temperature and moisture regime stays within a certain range.

But what happens when whole parts of the continent are completely covered by ice like with the large ice sheets? These plants under the ice sheets do not have enough time to “move”, nor can they move that far with simple animal relocation. They are completely covered over with ice and those plants — more specifically, those lineages — are no longer. So, imagine a common plant from Alaska that grows all the way down to the colder parts of the Great Lakes. This common plant would be “connected” by migration of mostly birds in that their lineages are regularly getting additions from a neighboring lineage (seeds dropping from birds). If this common plant had a relatively continuous habitat from Alaska to the Great Lakes for 1,000s of years and then had a huge, continental ice sheet cover up the area between them in a very short period of time, this once continuous line of related lineages is broken into two. You end of up with one set of lineages now doing its thing up north and another down south. Over the 1,000s of years that this ice sheet was covering North America, these two new lineages are now genetically different from one another. They have had enough generations to adapt specifically to their unique area without the introduction of new lineages.

This scenario of two separate but distantly related lineages, one in Alaska and another in the Great Lakes (for example) has a name in the field of phylogeography: disjunct distribution. We now observe related species, or one species with distinct genetics, in areas that were separated by the ice sheets from Alaska to many areas south of the ice sheets. These areas include the Driftless, the northern edges of the Great Lakes, Laramie Plains, Big Horns, the Rockies, and the list goes on. The area in Alaska where these lineages continued to thrive during the LGM is called the Beringia. Now, I can write a whole newsletter just on the concept of Beringia, but I’ll do my best to keep it short.

Beringia is the unglaciated land mass that stretched from the Lena River in Russia to the Mackenzie River in Canada (click here to read more about Beringia from NPS). Its northern border was the Arctic ice cap and the Brooks Mountain ranges. Its southern border was the Bering Sea and the Denali-Alaska Ranges. It has been determined already that Beringia served as a refugia (safe haven) for plants and animals of the Arctic during the Quaternary numerous times. In fact the Bering Land Bridge is now estimated to have surfaced at least 17 times. It has also been observed to be integral in the genetic incubation of plants and animals between the Asian and North American continents, including humans, for an estimated 40,000 years. This theory, named the Beringian Standstill Theory, is currently accepted by many in the field, but requires further study, specifically with population-level genetic studies.

Population genetics can help us understand how species’ populations have grown, retracted, been split, diverged, and maintained a healthy amount of genetic diversity. When a species has high amounts of genetic diversity it is less likely to become extinct over time and have lower levels of inbreeding which can result in poor health. These kinds of studies are imperative to understand our habitats in peril, like those in the Arctic and alpine.

The Beringian Botanists, we like to call ourselves, contributed to the collection of plant samples for the largest multi-year population genetic project proposed that I know of (in my little universe). They did this by targeting a set of species with disjunct lineages between the southern edge of the large North American ice sheets and Beringia. We also targeted species that would have relatively “stable” populations over time, which means those that are on the rocky tundra, rather than those of wetland habitats that were regularly disturbed by extreme and regular water changes. This year, the Beringian Botanists hunted plants with Beringian distributions in the tundra in areas that had not been glaciated during the Pleistocene. We did end up collecting a couple of species that are circumpolar (i.e. grow all over the northern latitudes), which means we need to visit the whole polar region to complete that dataset, but oh, shucks 🙂 Our goal was to find the oldest lineages possible that would have a genetic signature of historic Beringia plant movements.

In the spring of 2020, a group of students, pre-covid, attended a 2-credit hour seminar with me to discuss the biology surrounding Beringia and helped create the field plan for the summer. Life had other plans, and the whole trip was postponed for 2022. We again met weekly for 1 hour a week in the spring of 2022 to discuss all aspects of Beringian history and biology, phylogeography, and methods used to investigate questions regarding plant distributions. The group created a list of over 1,000 species to target, and we continued to investigate the species list to bring it down to a workable 100, and in the field targeted about 50.

In the 30-day field trip, our group had 11 non-consecutive days of field work, collected 19 different species at the population level, sampled 9 main populations with multiple species per population, and in many cases multiple sub-populations, collected ~2,300 individual leaf samples for DNA analysis, and more than 300 herbarium vouchers. This means we collected 77 population sets (leaf tissues from different populations and species). We also made over 2,000 observations of plants and animals with the crowd-sourcing biodiversity cataloging system, iNaturalist.org (link here to our project). Given that Alaska has very few roads, we were limited by access, but could easily target an unglaciated geological formation along the Dalton Highway, the Ruby Terrain, in the Alaska Interior, and the unglaciated tundra of the Seward Peninsula that is surrounded by the Bering Sea, Bering Strait, and Arctic Ocean (check out our map by Cooper Lyons).

Map of our route and collection sites. Created by Cooper Lyons with ArcGIS.

This targeted sampling is part of a larger, multi-year project to understand our question about plant population evolution during the Ice Ages, and the students gained experience in many other aspects of field work and field botany. Every site we visited the students became proficient in how to describe a population: the density, species diversity, size, and overall intactness (vs. decimated by humans). They learned how to sample plants for DNA analysis, press plants for herbarium preservation, and how to use field guides and keys. Almost more importantly, they learned the process of planning field work, choosing collection species and sites, and how to go about working in small groups while camping to achieve set field goals in a short period of time. More than half of the 20 students on the excursion have plans to work for the government in one way or the other in field biology, which is so great! They had the opportunity to meet and work with field ecologists, botanists, archeologists, and interns for the National Park Service (NPS), Bureau of Land Management (BLM), and Native Corporations. They visited the largest natural history museum of Arctic collections, the Museum of the North, at the University of Alaska-Fairbanks. These students are now able to take what they learned about sampling populations and apply it to their work or research in the future.

Now that I’ve explained more about why we went to Alaska and what we did there, I will take you through our trip. Please scroll all the way down to our photo gallery to see more details!

In July 2022, we boarded a plane in Madison and landed in Fairbanks with all our gear. While getting settled into our camping groups, we visited the boreal forest, the Museum of the North, at the University of Alaska-Fairbanks and prepared for the first major leg of our trip. The Director of the University of Alaska Fairbanks Herbarium (ALA), Dr. Steffi Ickert-Bond, prepared presses for us to use for our entire trip and gave us a tour of the herbarium. We spent a couple of days at the herbarium looking at plants, meeting with Carolyn Parker, retired botanist of ALA, and acquainting ourselves with the methods of collections and population assessments. David Swanson, ecologist for the NPS, gave us an ecological tour of the boreal forest surrounding Fairbanks. They were shown an area of degrading permafrost compared to seeing it intact and healthy. After these few days in Fairbanks, we loaded up our three rental vans to start our first leg of the expedition.

During this portion of the trip on Athabascan tribal lands, we traveled along their historic route from the three rivers area surrounding Fairbanks to the Brooks Mountains, now called the Dalton Highway. Our travel was by three vans and we camped at three campsites for six days. Our collections were focused on tree-less, granitic, tundra communities, and at one point we even collected plants in the snow. Our beautiful BLM campsites were both north and south of the Arctic Circle. The location of the Dalton Highway allowed us to hunt for our target species on the unique LGM-unglaciated geological formation called the Ruby Terrain. We hypothesize that these formations acted as refuges for plants during glaciation cycles, seasonal snow melt, and natural river expansion and retraction. The furthest north we went was just into the Brooks Mountains at Atigun Pass at the Continental Divide, where we collected in the snow. Our main collection sites along the Ruby Terrain were at Finger Mountain and Gobbler’s Knob. Additionally, we collected at Wickersham Dome, which is closer to Fairbanks.

After six days on the Dalton Highway, we dropped our pressed plants off with Dr. Ickert-Bond at ALA, and spent the night in Fairbanks before heading to Anchorage the next day. We took a charter bus from Fairbanks to Anchorage, stopping in Denali to hike Bison Gulch and see how different the habitat is in areas that were glaciated in the past. While on that sleepy day trip to Anchorage we also visited the huge visitor center of Denali National Park! I highly recommend it. While in Anchorage, we attended the international conference “Botany 2022” as a group. Many presented their own research, took field trips in the neighboring Chugash Mountains, visited the local botanical garden, and even went on a whale tour. I participated in a symposium focused on Beringia where I presented the course design and emphasized the need for large-scale population genetics training and work.

After the conference, we flew on Alaska Airlines with all our luggage and carry-on plant presses to Nome on the Seward Peninsula overlooking the Bering Sea. This little gold mining town, home of the Inupiat, was our base for the remaining 11 days of the trip. We settled into our third leg of the trip while staying at Aurora Inn in Nome for a couple of days to reorganize our field equipment, visit the local cultural center and library, and connect with our new colleagues at the BLM and NPS. We loaded up a new set of vans like “old pros” for our next six days in the field.

Our first field day on the Seward Peninsula was at Anvil Mountain, a small mountain that overlooks the town of Nome. I had to pinch myself numerous times as I looked up from my Claytonia collecting to see the Bering Sea shining in the sun right in front of us in all its glory. After collecting at Anvil Mountain, we drove north to a picturesque BLM campsite on Salmon Lake, collecting and hiking in the tundra above the Kougarok Road. We were lucky to have wildlife, such as musk ox, grizzly bears, ptarmigans, and red foxes, allow themselves to be photographed, while we saw very little wildlife on the Dalton. We then went to the Bering Land Bridge National Preserve (BLBNP), north of the Bendeleben Mountains. We went there because we hypothesize that this centralized Beringian site holds the oldest lineages of Beringian plants.

The BLBNP is a special and sacred site for human rites of passage, migration, and trade fairs for time immemorial (or at least 40,000 years). It is accessible only by a 20-minute ride on a small plane, or a very long and arduous walk over some 3,000-foot-tall mountains, through peat-tussocks, and meandering rivers and streams. The landing strip is adjacent to the natural Serpentine Hot Springs and a small National Park Service (NPS) cabin. We were accompanied by the NPS field archeologist and local intern for BLBNP, for the duration of our stay of two nights and three days. Our group collected for three days along the granitic Tors (rocky towers) surrounding the hot springs like the sides of a bowl. We were told that the only similar geological formation like this in the world is in Scotland! We were lucky to have along a botanical expert from the Yukon, Bruce Bennett, who located the species for which the concept of Beringia was first studied by Eric Hultén, Primula tschuktschorum. After his finding, we were able to add this species to our population collections, too!

Our air taxi ride back to our vans was slightly delayed by 6 hours and put us back to our base camp at Salmon Lake late in the evening. As I had planned to visit a potentially large Draba population after we returned from the BLBNP, one student volunteered to retrace our drive back to the site at midnight. It was a first for me, collecting during a 1 a.m. sunset! What an experience for sure…

The last part of our trip was to visit the coastal tundra just a bit further west of Nome towards the town of Teller. The Beringians found a hyper-diverse site that put the “cherry on top” of the trip. During the last couple of days in Nome, we checked back into the hotel we had stayed in upon our arrival to Nome, the Aurora Inn, to rest, heal wounds, process our collections, eat our remaining groceries, and prepare for our flights back to Madison. We ate a hearty dinner at the Bering Sea Restaurant, had a potluck dinner with our new friends from the National Park Service, BLNNP, and sang karaoke with the locals. Some of us even took a swim in the Bering Sea. I think it is safe to say that life-long friends were made within our group, and possibly also with our new Nome-ites.

If you would like to follow the progress of the project and learn more about the plants we targeted and collected, please return to this webpage as I will continue to update it. For the photos, please scroll down to the photo gallery. We will be depositing our herbarium specimens in the Wisconsin State Herbarium-WIS, the Museum of the North-ALA, and the BLBNP specimens at the University of Alaska Anchorage-UAAH. The population genetic work will not be happening until we have collected more specimens from south of the ice sheets. Also, the funding for the genetic work has not yet been determined. Please contact me if you are interested in helping to finance the genetic work at jordonthaden < @ > wisc.edu. To contribute funding for more field classes like this in our department, please donate to the Humboldt Endowment for Field Botany (fund number 132160002).

We would like to thank the following people who helped with the planning, permitting, and execution of the expedition: lead Instructor: myself, Dr. Ingrid Jordon-Thaden; Teaching Assistants: Alexa DiNicola and Cara Streekstra; Botanical Experts: Bruce A. Bennett, Yukon Government – Director of Yukon Herbarium, Mary-Ann Feist – Wisconsin State Herbarium. Collaborators: Prof. Ken Sytsma – University of Wisconsin-Madison, Carolyn Parker – Fairbanks, AK, Prof. Steffi Ickert-Bond – Director of ALA at UAF Museum of the North, David K. Swanson – ecologist, NPS Arctic Inventory and Monitoring Network, Katie Ollesch – archeologist, NPS, Bering Land Bridge National Preserve. Permit Coordinators: Jim Herriges – BLM Eastern Interior Field Office, Sheri Wilson – BLM Central Yukon Field Office, Nikki M. Braem and Jeanette Koelsch – NPS Bering Land Bridge National Preserve, Aliza Segal – BLM Anchorage Field Office, Paula Johnson and Charles Ellanna – Sitnasuak Native Corporation, Larry Pederson and Kevin Bahnke – Bering Straits Native Corporation, and Tom Sparks – BLM Nome Field Station.