It is starting to feel like fall, although there are not many colors in the trees yet.
The colors were vivid on the day pictured in the painting below, and I fondly remember a really great hike through a hemlock-dominated ravine as part of this camping trip a few years ago. The painting was an attempt to capture a moment that I spent watching my daughter as she sketched in her notebook.
For me anyway.
One of the highlights of being an ecologist is spending time in the field making observations, thinking about patterns, asking questions, and collecting data to answer those questions. In fact, it is hard to believe that we call this stuff “field work,” because as anyone that spends time in the natural world knows, simply getting out there can be a tremendous source of inspiration and rejuvenation. One of the ways that I reconnect to the splendor of “field work” is to paint. Now that the fall semester is over, I’m looking forward to spending a little time painting with my daughter. In the spirit of the holiday, below I share a few field-site and field-related paintings that have special meaning to me….
October at Fallison Bog. Fallison Bog Pond is a small peatland pond in northern Wisconsin, near the Trout Lake Limnological Research Station. The place is particularly significant for me – for both personal and professional reasons. We have been monitoring testate amoeba communities and hydrology of the bog, and other bogs in the region, every few years since 2003 (see here for more on testate amoebae). Also, we are currently investigating processes controlling peatland development, and Fallison Bog is a critical site in this effort.
The bog was also one of the first field sites that I dragged my future wife into, in a memorable trip in April of 2004. She learned the hard way that sometimes bog mats are pretty thin along the lake edge. Wisconsin water is very cold in April.
Erythrina herbacea. St. Catherine’s Island is a barrier island along the coast of Georgia in the southeastern United States. I was fortunate to spend time on the island in 1996-1998 as part of my masters thesis research on the vegetation history of the area. At the time, I was really immersed in field botany; in fact, most of the time that I wasn’t spending on my thesis research was spent collecting and identifying plants. This specimen of Erythrina herbacea caught my attention, something about the subtle beauty of the red flowers rising from the chaos of the downed tree, all against the backdrop of the quiet sound behind the island. I gave this painting to my masters thesis advisor – a truly fantastic person and one of the most genuine people I have ever met.
Henderson Peatlands. Peatlands are not particularly common in the central and southern Rocky Mountains, but where they do occur, they offer unique habitat and striking visual contrasts with the surrounding landscape. I fondly recall the field work for a project in 2002 that required sampling testate amoebae and vegetation in numerous peatlands in Colorado and Wyoming. I was particularly impressed by this vista from near Josephine Lake (3535 m elevation) in Colorado. From the ridge above the lake, two peatlands could be seen to the south nestled in the surrounding deep-green forest. Informally named the Henderson peatlands, after the nearby Henderson Park Trail, these peatlands contained three species of Sphagnum (S. russowii, S. platyphyllum, and S. warnstorfii) and a diverse association of testate amoebae.
Evening on Au Train Lake. A portion of summer 2000 was spent in Upper Michigan working with a team of researchers on a project focused on understanding the past water-level fluctuations of Lake Superior, and the impacts of climate changes on coastal wetlands. The peat coring was exhausting, fraught with equipment difficulties and woody peats, and the deer flies were thick. But it didn’t matter….this was Upper Michigan. I have pleasant memories of sitting in front of the cabin, keying out wetland Carex species, and talking ecology and geology with good friends and colleagues. The cabin was only a couple miles inland from Lake Superior, and almost walking distance from our field sites.
Salt marsh and hammock. Another one from St. Catherine’s Island; the location of this scene was very close to where I collected one of the sediment cores used in my masters thesis. One species of grass, Spartina alterniflora, dominates most of the salt marsh on the east coast of North America. Although there is low botanical diversity in much of the extensive lower portion of these salt marshes, they are highly productive ecosystems with some very unusual biogeochemical processes. I can almost smell the hydrogen sulfide when I look at this one.
Tahquamenon Falls. Another one from Upper Michigan. The Tahquamenon River drains extensive areas of cedar swamp and peatland, making the water dark and humic-stained. During several years of field work in Upper Michigan, this was a nice late afternoon or evening destination when a break was needed. The area is a common tourist attraction, and apparently the location of Henry Longfellow’s “The Song of Hiawatha.” A nice hike to the waterfalls (there are actually two of them) through hemlock, yellow birch, and white pine forest can be followed by a good beer at the Tahquamenon Brewery.
Canoeing with Clea. This one is not really a field site but I’ll end with it because it brings back particularly strong positive feelings. It captures a moment spent with my daughter exploring the riparian wetland adjacent to a small creek connected to Promised Land Lake in the Poconos of Pennsylvania. This was her first time on water, and it was a truly spectacular day enjoying nature.
Happy holidays. Recharge and seek inspiration. Spend some time with family doing what you love.
Plants are the structural foundation of wetlands, and particular species and growth forms are indicative of different wetland types because of their sensitivity to hydroperiod, hydrodynamics, nutrient availability, and other environmental conditions. The identification of wetland plant genera and species is therefore critically important to research, management, and conservation efforts, and is a fundamental part of wetland delineation for regulatory purposes.
Learning plants as part of a wetland ecology course in the spring semester is challenging, because field trips typically don’t occur until the last few weeks of the semester, and even then not too many plants have emerged from their winter slumber. So in wetland ecology at Lehigh University, students examine, draw, and learn some important wetland plant species and genera from herbarium specimens and other materials, so that they are already experts by the time we go into the field. The act of drawing the specimens forces the students to focus and develop their observation skills, a critical (and often under emphasized) part of the scientific process.
But what plants should a student know? The list below, what I like to call the “top 75,” is certainly a work in progress. It is composed of mostly of taxa that are typically encountered in eastern North America, and many of the species were selected because we can observe them locally; however, many of the same genera occur in wetlands throughout the world. The plants on the list range from facultative (i.e., found in both uplands and wetlands) to obligate (i.e., virtually always found in wetlands) taxa. I’d love to hear suggestions for additions, deletions, or substitutions.
Plants that every self-respecting* wetland ecologist should know.
I. Salt-to-brackish marsh plants
- Spartina alterniflora (Saltmarsh cordgrass) (USDA, Wikipedia)
- Spartina patens (Saltmeadow cordgrass) (USDA, Wikipedia)
- Distichlis spicata (Spike grass) (USDA, Wikipedia)
- Juncus gerardi (Black grass) (USDA, Wikipedia)
- Limonium carolinianum (Sea lavender) (USDA, Wikipedia)
- Salicornia spp. (Glasswort) (USDA, Wikipedia)
- Iva frutescens (Marsh elder) (USDA, Wikipedia)
- Phragmites australis (Common reed) (also common in freshwater) (USDA, Wikipedia)
II. Freshwater marshes and swamps
- Elodea canadensis (Water-weed) (USDA, Wikipedia)
- Myriophyllum spp. (Water-milfoil) (USDA, Wikipedia)
- Najas spp. (Waternymph) (USDA, Wikipedia)
- Potamogeton epihydrous (Ribbon-leaved Pondweed) (USDA, Wikipedia)
- Potamogeton crispus (Curly Pondweed) (USDA, Wikipedia)
Floating-leaved plants and floating plants
- Azolla caroliniana (Mosquito fern) (USDA, Wikipedia)
- Brasenia schreberi (Water-Shield) (USDA, Wikipedia)
- Lemna minor (Lesser Duckweed) (USDA, Wikipedia)
- Nuphar advena (Yellow water-lily, spadderdock) (USDA, Wikipedia)
- Nymphaea odorata (Fragrant Water-Lily) (USDA, Wikipedia)
- Nymphoides aquatica (Big floating heart, banana plant) (USDA, Wikipedia)
- Salvinia spp. (Salvinia) (USDA, Wikipedia)
- Utricularia spp. (Bladderwort) (USDA, Wikipedia)
- Wolffia spp. (Watermeal) (USDA, Wikipedia)
Emergents and plants of wet ground
- Acorus calamus (Sweet flag) (USDA, Wikipedia)
- Arisaema triphyllum (Jack-in-the-pulpit) (USDA, Wikipedia)
- Boehemeria cylindrica (smallspike false nettle) (USDA, Wikipedia)
- Carex stricta (Tussock sedge, many species of Carex occur in wetlands) (USDA, Wikipedia)
- Eleocharis palustris (Common spike-rush) (USDA, Wikipedia)
- Equisetum fluviatile (Water horsetail) (USDA, Wikipedia)
- Impatiens capensis (Jewelweed) (USDA, Wikipedia)
- Iris versicolor (Blue flag) (USDA, Wikipedia)
- Juncus effusus (Common rush, many species of Juncus occur in wetlands) (USDA, Wikipedia)
- Lythrum salicaria (Purple loosestrife) (USDA, Wikipedia)
- Onoclea sensibilis (Sensitive fern) (USDA, Wikipedia)
- Osmunda cinnamomea (Cinnamon fern, now Osmundastrum cinnamomeum) (USDA, Wikipedia)
- Osmunda claytonia (Interrupted fern) (USDA, Wikipedia)
- Osmunda regalis (Regal fern) (USDA, Wikipedia)
- Peltandra virginica (Arrow-arum) (USDA, Wikipedia)
- Polygonum spp. (Smartweed) (USDA, Wikipedia)
- Pontederia cordata (Pickerel-weed) (USDA, Wikipedia)
- Sagittaria latifolia (Common arrow-head) (USDA, Wikipedia)
- Saururus cernus (Lizard’s tail) (USDA, Wikipedia)
- Schoenoplectus tabernaemontani (was Scirpus validus) (Softstem Bulrush) (USDA, Wikipedia)
- Sparganium eurycarpum (Common bur-reed) (USDA, Wikipedia)
- Symplocarpus foetidus (Skunk cabbage) (USDA, Wikipedia)
- Typha angustifolia (Narrow-leaved cattail) (USDA, Wikipedia)
- Typha latifolia (Common cattail) (USDA, Wikipedia)
- Viola cucullata (Blue marsh violet) (USDA, Wikipedia)
Swamp (and peatland) trees (several of these are more common in uplands, but are not infrequent in wetlands of the region)
- Acer rubrum (Red maple) (USDA, Wikipedia)
- Larix laricina (Tamarack) (USDA, Wikipedia)
- Nyssa sylvatica (Blackgum) (USDA, Wikipedia)
- Picea mariana (Black spruce) (USDA, Wikipedia)
- Pinus strobus (white pine) (USDA, Wikipedia)
- Taxodium distichum (Bald cypress) (USDA, Wikipedia)
- Taxodium ascendens (or Taxodium distichum var. nutans) (Pond Cypress) (USDA, Wikipedia)
- Thuja occidentalis (Northern white cedar, arborvitae) (USDA, Wikipedia)
- Tsuga canadensis (Eastern hemlock) (USDA, Wikipedia)
- Alnus spp. (Alder) (USDA, Wikipedia)
- Cephalanthus occidentalis (Buttonbush) (USDA, Wikipedia)
- Decodon verticillatus (Swamp loosestrife) (USDA, Wikipedia)
- Ilex mucronata (Catberry) (USDA, Wikipedia)
- Lindera benzoin (Spicebush) (USDA, Wikipedia)
- Rosa palustris (Swamp rose) (USDA, Wikipedia)
- Salix spp. (Willow) (USDA, Wikipedia)
III. Peatland plants
- Andromeda polifolia (Bog rosemary) (USDA, Wikipedia)
- Betula pumila (Bog birch) (USDA, Wikipedia)
- Chamaedaphne calyculata (Leatherleaf) (USDA, Wikipedia)
- Drosera spp. (Sundew) (USDA, Wikipedia)
- Eriophorum virginicum (Cottongrass) (USDA, Wikipedia)
- Ledum groenlandicum (Labrador tea, now Rhododendron groenlandicum) (USDA, Wikipedia)
- Menyanthes trifoliata (Bogbean) (USDA, Wikipedia)
- Rhynchospora alba (White beaksedge) (USDA, Wikipedia)
- Sarracenia purpurea (Purple pitcher plant) (USDA, Wikipedia)
- Sphagnum spp. (Sphagnum moss) (USDA, Wikipedia)
- Vaccinium oxycoccus (Cranberry) (USDA, Wikipedia)
*Obviously meant in fun. Seems unlikely that less botanically inclined wetland ecologists really have less self-respect…
Gunnar Erdtman, a Swedish botanist, is usually credited for bringing the technique of pollen analysis (often referred to as palynology) to the world (Fægri 1973, Nilsson & Praglowski 1978,Traverse 2007). Influenced by a now famous 1916 lecture on pollen analysis given by Lennart von Post, Erdtman’s 1921 thesis was the first major palynology publication in a broadly accessible language (Fægri 1973). He traveled widely, promoting palynology as a tool to study past vegetation and climate, and developed laboratory techniques still used in studies of pollen morphology today (e.g., acetolysis). Furthermore, he published over 200 papers and several books that established the foundation of the science. But this post is not really about Erdtman’s scientific contributions; it is a simple celebration of what Fægri (1973) referred to as his “artist’s perception of forms.”
“Erdtman was a keen observer and had a capacity for imaginatively demonstrating his findings with the talent of an artist […] and the pedagogical skill of a teacher.” – Nilsson & Praglowski 1978
Gunnar Erdtman’s artistic gifts and observation skills were likely inherited, inspired, and cultivated by his family. His father, Elias Erdtman, was a well known landscape painter that studied in France at the height of French Impressionism, and there were artists on his mother’s side as well. He grew up broadly interested in both art and music.
When he wasn’t using his artistic talents to observe, describe, and document the morphology of pollen grains he apparently enjoyed entertaining his friends with his flute playing, and creating surrealistic drawings (Nilsson & Praglowski 1978), like the “self-portrait” below.
Pollen grains are strikingly intricate and beautiful, and Erdtman’s passion for art may have contributed to his interest in palynology. However, his power as an artist also clearly benefited him as a scientist. Although almost anyone can learn to identify the general morphological types of pollen, skilled observations are needed to discern the finer structural details of pollen-grain walls and the subtleties of surface texture that enable greater taxonomic precision. Erdtman was keenly observant of these details. His observations and meticulously detailed drawings laid the foundation for pollen analysis and established much of the terminology that is still used today to describe pollen features. I recently looked through Erdtman’s 1954 textbook on pollen analysis, and was struck by the detail and beauty captured in his drawings (shown below).
Art informs science by focusing the scientist’s observation skills. Science informs art by providing endless source material for the artist. And both can inspire each other.
Finally, I can’t resist adding this humorous anecdote:
“Professor Erdtman’s devotion to palynology was unmistakable and expressed itself in many different ways. On napkin holders in various hotels he introduced himself and his wife as “I. M. Pollen” (I am pollen) and “U. R. Pollina” (you are pollina) respectively. As a consequence it was only natural to imagine and discuss during the meal, which pollen types were represented in the mixed salad being served. Thus, a good palynologist should never lose an opportunity to test his or her knowledge in the beloved science of palynology.” – Nilsson et al. (1993)
- Erdtman, G. 1954. An introduction to pollen analysis. Chronica Botanica Company. 240 p.
- Fægri, K. 1973. In memoriam O. Gunnar E. Erdtman 1897-1973. Pollen et Spores 15: 5–12.
- Nilsson, S. & J. Praglowski. 1978. Professor Gunnar Erdtman 1897-1973. Grana 17: 1–4.
- Nilsson, S., V. Ukraintseva, & G. El-Ghazaly. 1993. Professor Gunnar Erdtman (1897-1 973). Grana (Suppl. 2): 1-2
- Traverse, A. 2007. Paleopalynology. Second Edition. Springer. 813 p.
I recently went to the Milwaukee Public Museum with my family. This destination was carefully chosen because they have a butterfly exhibit, and my 5-year old daughter has developed a butterfly obsession. In my experience, obsession of this sort is a good thing; in fact, it is the kind of thing that got me into science in the first place. After I proudly watched her carefully hold and observe the different species of butterflies, and even have a few pleasant conversations with them, I wandered the exhibit and observed the diversity of colors and shapes myself. There were some really spectacular species.
A butterfly amoeba
Perhaps because I recently had reason to open up Joseph Leidy’s incredibly beautiful 1879 foundational work describing North American testate amoebae (a group of amoebae that construct and live inside tests, or shells), my mind drifted to a statement Leidy made comparing a particular species of testate amoeba to a butterfly. Apparently the simple beauty and elegance of this particular testate amoeba caused him to radically change his research focus. He became obsessive about testate amoebae, or rhizopods as he called them. As with his previous research activities (e.g., paleontology, parisitology), his contributions to this new research area were enormous.
The testate amoeba in question was Hyalosphenia papilio. In Leidy’s words:
“No other lobose rhizopod has more impressed me with its beauty than this one. From its delicacy and transparency, its bright colors and form, as it moves among the leaves of sphagnum, desmids, and diatoms, I have associated it with the idea of a butterfly hovering among flowers.“
Leidy notes that he first observed the species thirty years prior to the publication of his seminal work, and seeing the species brought him fond memories of his explorations in the New Jersey pine barrens:
“Upward of thirty years ago, while examining the structure of sphagnum, my attention was distracted by the movements of a singular animal, whose character and affinities I did not then recognize.”
“This interesting Rhizopod, together with a profusion of other remarkable microscopic forms of both animal and vegetal life, of which many are novel and yet undescribed, recalls pleasing recollections of excursions into the sphagnous bogs, cedar swamps, and pine barrens in the southern region of New Jersey.“
His fondness for the species is particularly evident in the next quote. I can’t help to laugh a bit at the image of him breaking out the microscope at a holiday dinner party, in order to display his “pets” to his friends. Perhaps I should try this the next time I host a lab get together!
“I have collected it from early spring to late autumn, and have retained it alive in sphagnum, in a glass case, through the winter. During the Christmas holidays, I have repeatedly exhibited it, in the living condition, to the admiration of friends.“
What I find most interesting about this, is that Leidy was 50 years old when he decided to pursue this new line research. He apparently dropped all of his other research endeavors, and focused solely on investigating these simple organisms for four or five years. This shift in research focus was made by an already famous man who described the first complete dinosaur fossil, as well as many other North American fossils, and was widely recognized as the leading expert in parasitology.
His obituary in the Proceedings of the National Academy of Arts and Sciences suggests that he left his paleontological research because of the extreme rivalries and unfriendly arguments that were shaping the field at the time – rather than get involved in these controversies Leidy may have just moved on. He certainly would not be the only scientist to do such a thing. However, according to his own words, it was the beauty of Hyalosphenia papilio that led him to study testate amoebae:
“September 9th, 1873, the fiftieth anniversary of my birth, a friend, Clarence S. Bement, presented me with a Hartnack microscope, which, from its convenient size and form, I kept on my study table. From time to time I was led to make observations on Fresh-water Rhizopods detected in sediments collected in the vicinity of Philadelphia. A year later, in examining water squeezed from sphagnum obtained at Absecom, I observed many individuals of the same singular animal above indicated, but now, understanding its nature, I described it as Difflugia (Hyalosphenia) papilio. It was the rediscovery of this beautiful form which impelled me to pursue the investigations which constitute the material of the present work.”
Published in 1897, his “Freshwater Rhizopods of North America” is a stunning combination of science and art, and still the most exhaustive description of North American testate amoebae. For an interesting read on Leidy and the culture of science in mid-1800s North America, pick up a copy of Leonard Warren’s “Joseph Leidy: The last man who knew everything.” For more on Leidy and a wonderful online version of the drawings included in the 1879 masterpiece, go here and here.
Leaping the hedges
The idea of following one’s interests, wherever they take you, is very attractive to me. Of course, the culture of science has changed dramatically since the 1800s and scientists are generally narrower in focus and constrained by institutional expectations of tenure and promotion. However, Leidy’s path of scientific exploration still seems a natural one, and I suspect that if more scientists followed his model instead of obsessively chasing promotion or the next big grant, we would collectively learn more about the natural world.
When I interviewed for a faculty position one of the questions that I was asked was to describe my 5-year research plan. I was prepared for such a question, as it seemed like the sort of thing that I would be asked. In fact, I carefully designed my research talk (candidates in academia usually “interview” for several days, typically giving one or two public lectures) to incorporate aspects of my long-term research plan. Seven years later, perhaps not surprisingly, the most interesting science that I have done had little to do with my “plan.” The projects that have excited me the most have been the things that I or my students have stumbled upon…things that I never could have planned.
I sincerely doubt that Joesph Leidy had a plan. Sometimes something as simple as a beautiful amoeba, or a colorful butterfly, or perhaps an amoeba reminiscent of a butterfly…. can lead a scientist to wonderful new places. Hopefully they will lead a certain 5-year old girl to some interesting places too. The trick is identifying and following your passions (and obsessions), and knowing when it is time to move on to something new. Leidy knew both…and he said so in the concluding statements of his great work:
“”I may perhaps continue in the same field of research and give to the reader further results, but I cannot promise to do so; for though the subject has proved to me an unceasing source of pleasure, I see before me so many wonderful things in other fields that a strong impulse disposes me to leap the hedges to examine them.””
After posting I ran into this great piece. A nice example of testate amoebae as inspiration for art.