Getting the Most Out of Herbaria: Systematics and Chemistry

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Murder Most Florid by Mark Spencer, London: Quadrille, 2019

As mentioned in the last post, herbaria, both real and virtual, are most frequently visited by taxonomists, who are usually studying particular plant taxa or preparing flora of areas ranging in size from city parks to entire countries.  These are the traditional uses of plant collections and are still crucial.  However, several things have changed.  Now the “visit” is often to digital portals rather than onsite, making it much easier for researchers to look at specimens from far-flung institutions, IF the material has been digitized, and particularly if it is available through aggregators such as iDigBio, GBIF or JSTOR Global Plants with their links to massive numbers of specimens.  Still, coverage is uneven, with some collections more fully digitized than others.  Also changed is the way taxonomic information, once generated, is distributed.  Many flora are now published virtually, with or without an accompanying paper format.  The 2012 International Code of Nomenclature for Algae, Fungi, and Plants made it acceptable to publish descriptions of new species digitally as long as they were responsibly published and properly archived.

Plant taxonomy is also changing because of its increasing links with genetics.  Most treatments of species and genera now include DNA sequencing data.  While this has been going on for decades, the last ten years or so have seen greater use of DNA data derived from samples taken from herbarium specimens, with NGS, next-generation sequencing (NSG) making this possible. NGS techniques utilize small pieces of degraded DNA found in dried plant material easier to sequence and to determine how such sequences fit together to provide meaningful results.  That this work has revolutionized taxonomy is hardly news.  Still, it is interesting to look at how the information has solved various puzzles, such as the origin of European potatoes or the origin of the pathogenic Phytophthora strain responsible for the Irish potato famine of the 1840s.  In a study of the genetics of grapes, researchers used over 200-year-old specimens from the herbarium at the Royal Botanical Garden in Madrid.  These plants were collected by Simón de Rojas Clemente y Rubio, considered one of the founders of the botanical study of grape vines, especially varieties used in wine-making.

DNA is not the only chemical being extracted from specimens to glean useful information about plants and also about their ecological relationships.  For example, researchers in Copenhagen tested specimens of four species of Salvia used for medicinal purposes for levels of terpenoids, known to have medicinal applications.  These plants were collected over the past 150 years.  While the terpenoid levels did decrease with the specimen’s age, the “chemical composition of four Salvia species are predominantly defined by species, and there was a substantially smaller effect of year of sampling.  Given these results, herbarium collections may well represent a considerably underused resource for chemical analyses.”  Also being investigated are secondary metabolites that plants produce to control herbivore damage.  In one study researchers were able to extract pyrrolizidine alkaloids from plants in the Apocynaceae family that includes milkweed.  The specimens were as much as 150 years old, and even in those treated with alcohol or mercuric chloride, alkaloids were detectable.

There has also been work on the presence of heavy metal pollutants in collections as a way of tracking contamination.  A study at Brown University in Providence, Rhode Island analyzed samples from specimens collected around the city from 1846 to 1916, compared with newly collected ones.  Levels of copper and zinc remained relatively consistent, but lead levels were much lower in plants growing in Providence today.  It was impossible to test accurately for another toxic heavy metal, mercury, because mercuric chloride was so often used to prevent insect damage to specimens.  While toxic metals in plants might make them seem less palatable as food sources, there is an emerging field of agromining:  growing plants that are hyper-accumulators of metals like lead and mercury to eventually reduce soil contamination.  Herbarium specimens can be used to discover how long areas have been contaminated and also to identify species that are particularly good at extracting metals.  There are even some who think that growing plants in nickel-rich soil could be a way to extract this metal for sale.

Such studies suggest that the possible uses of specimens are only limited by the ingenuity of researchers in coming up with them.  It is fun to see what they can ferret out.   The British botanist Mark Spencer recently published a book on his work as a forensic botanist.  It has a great title:  Murder Most Florid (2019).  He was at the herbarium at the Natural History Museum, London curating the British and European collections when he was first asked by the police to aid in a murder investigation.  Human remains have been found in a forested area and had apparently been there for several years.  Would he be able to determine the time more precisely by studying plants at the site?  I don’t want to spoil this story or the other great ones in the book, but I will say that Spencer explains why a herbarium is essential for the work he does, now that he has become much more involved in forensics.

Reference

Spencer, M. (2019). Murder Most Florid: Inside the Mind of a Forensic Botanist. London, UK: Quadrille.

Getting the Most Out of Herbaria

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Representation of Digitization 2.0 from “Digitization and the Future of Natural History Collections,” Hedrick, et al., BioScience, February 2020.

In our culture there is a direct connection between usefulness and value, so it’s not surprising that the arguments for preserving natural history collections entail how useful they are in many scientific endeavors.  The late Smithsonian taxonomist, Vicki Funk, is well-known for her 2003 commentary, “100 Uses for an Herbarium (Well at Least 72).”  More recently there have been articles on how collections have been utilized in the past and on how they could be employed in the future.  These studies take into account how specimen digitization is opening new ways of employing specimens in biological inquiry.  This series of posts will deal with some of these avenues, beginning with the general overview presented here.

Last fall, Heberling, Prather, and Tonsor published an article (2019) that reported on a computational text analysis of over 13,000 journal articles published between 1923 to 2017 and dealing with plant collections.  Investigation of the abstracts categorized the research into 22 topics ranging from taxonomic monographs and revisions as the most common, to morphology and anatomy ranking twenty-second.  Taxonomic work rated as most frequent throughout the study period and for most subtopics in this area the output was relatively steady over time.  However, the authors found that more recently, there have been a wider variety of topics employing herbarium specimens.  These include DNA sequencing of specimen samples and investigations of shifts in phenology over time, along with other measures of environmental change.

While there is nothing particularly shocking about the findings, this is still an important study.  First, it is broad in terms of both the time span and the number of articles covered.  Also, the authors used a rigorous methodology to come up with categories and to apply these to the texts.  Finally, this publication gives those in the natural history collection community a good citation in bolstering their case for the increasing importance of their work:  its increasing breadth promises to grow in the future if properly supported.  Another interesting, though narrower, survey in the same vein was conducted by researchers at the herbarium of the Natural History Museum, London (Carine et al., 2018).  They used 12 categories condensed from Funk’s longer list, analyzed articles published between 2013-2016 by means of the Web of Science, and then compared these results with a survey of researchers who visited NHM to use the herbarium.  In both approaches, taxonomic work ranked highest, but coming in second among the herbarium visitors was historical research.  This is in light of the herbarium’s large and rich historic collection including the herbaria of Hans Sloane and Joseph Banks.  The authors note that this number also reflects their recent work to encourage historical research.

While the studies just cited looked at past work, several publications highlight the bright promise of natural history collections in the digital age.  The author of one of these articles, “Collections-based science in the 21st Century,” is Vicki Funk (2018).  She notes that it is not only the great increase in specimen data now available on line that renders specimens so useful, but also the fact that what is called “next generation” DNA sequencing makes it more feasible and easier to sequence partially degraded DNA, the type found in most specimens.  This opens all kinds of possibilities for phylogenies based in part on specimen data as well as work in evolutionary medicine and ecology.  Georeferencing specimens also opens the way for several kinds of studies including niche modeling and climate change forecasts.

Shelley James and her coworkers give a long list of research projects using herbarium data:  “The addition of non‐traditional digitized data fields, user annotation capability, and born‐digital field data collection enables the rapid access of rich, digitally available data sets for research, education, informed decision‐making, and other scholarly and creative activities” (p. 1).  However, this bright future will only come about through investment of resources that go beyond just getting data online.  The information has to be properly coded so it can be easily retrieved in many different ways and integrated with a variety of other systems so that specimen data is tied to DNA sequences, as well as to ecological evidence and the taxonomic literature.  These are examples of what is coming to be called Digitization 2.0, that is, building on the initial digitization of label data and imaging by integrating this input with genetic and ecological data and by augmenting it with more sophisticated forms of visualization.

European researchers are coming to similar conclusions.  Besnard et al. list many of the same uses mentioned above, noting that this data can be helpful in managing genetic crop resources and monitoring crop pathogens.  Lang and her coauthors provide a good review of employing specimen data to study global environmental change with an emphasis on tracking climate change, the spread of invasive species, and on the effects of pollution and habitat change.  And while I don’t want to put a damper on these bold plans, Bingham et al. have written a comprehensive article on the large number of portals and other digital projects at various levels from the local to the international.  Many of these are not closely tied to or integrated with other projects, and some closely duplicate the efforts of others, so there seem to be too many cooks in the kitchen.  This doesn’t make sense in light of the limited financial and human resources available and the vast job to be done.  Despite this, there are some very interesting projects successfully using herbarium data, and I will touch on them in the next several posts.

References

Carine, M. A., Cesar, E. A., Ellis, L., Hunnex, J., Paul, A. M., Prakash, R., Rumsey, F. J., Wajer, J., Wilbraham, J., & Yesilyurt, J. C. (2018). Examining the spectra of herbarium uses and users. Botany Letters, 0(0), 1–9.

Funk, V. A. (2018). Collections-based science in the 21st Century. Journal of Systematics and Evolution, 56(3), 175–193.

Heberling, M., Prather, L. A., & Tonsor, S. (2019). The changing uses of herbarium data in an era of global change. BioScience, 69(10), 812–822.

Art and the Herbarium: Metaphor

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Cover of Lucian Freud Herbarium by Giovanni Aloi, courtesy of Prestel Publishing

In the last post, I discussed Anselm Kiefer and his use of dried plants, essentially herbarium material, in his multimedia paintings.  Here I want to begin with another artist whose name is linked to herbaria, at least metaphorically.  In Lucian Freud Herbarium Giovanni Aloi (2019) deals with paintings of plants that Freud created throughout his career, though Freud is much better known for his portraits, sometimes of nudes with less than perfect bodies.  I am always surprised and delighted when I discover artists known for other subjects who also painted plants:  the pop artist Jim Dine (Dine & Livingstone, 1994), the minimalist Ellsworth Kelly (Axsom, 2005), and two painters in the precisionist style:  Charles Sheeler (Troyen, 1987) and Charles Demuth (Peitcheva, 2016).  But here what I want to focus on is Aloi’s inclusion of the word “herbarium” in the book’s title.

The term “herbarium” was in use long before there were collections of preserved plants.  It is a Latin noun and was employed to refer to a book on plants, often illustrated.  For example, Otto Brunfels’s 1534 Herbarum Vivae Eicones was an early herbal, a volume on medicinal plants that had realistic illustrations.  This was about the same time that herbaria began to be created, but the term used for such a collection was usually the Latin hortus siccus, dry garden, or hortus hyemalis, winter garden.  Agnes Arber (1938) writes:  “The word “Herbarium,” in the modern sense, makes its first appearance in print—so far as the present writer is aware—in Pitton de Tournefort’s Elemens of 1694” (p. 142).  She is so often quoted on this that 1694 has become the birthday of the term, over 150 years after the first of its kind was created.

Those working in herbaria are often called on to describe their place of employment to family and friends.  Say the word, and people automatically think of growing and selling herbs, or being into health food or herbal medicine.  Their faces usually fall when it’s explained that herbaria house dead plants, all labeled with scientific names.  But the fact remains that the base of this term, herb, is the Latin word for herb or grass.  It has been tied to plant material for millennia, and “herbarium” continues to be used in a variety of ways, usually to describe some plant-related collection, as in the case of the Freud book.  I’d like to dig a little deeper into this metaphorical usage because it both causes some confusion—I have never heard that Lucian Freud, for all his interest in plants and his attention to rendering them realistically, ever had a herbarium.

The definition of a metaphor I like to use is that of the philosopher Max Black (1954).  He argues that a metaphor is different from a direct comparison:  saying metaphorically “man is a wolf” is different from saying “man is like a wolf.”  The metaphor is more powerful.  Though the two subjects have both similarities and differences, it is the similarities that are heightened in the metaphor.  So in the case of herbarium, using the term “Lucian Freud herbarium” highlights the fact that Freud painted a collection of plants as a way to preserve something of them visually even though he didn’t press the plants or dry them or paste them on to sheets of paper.  There have been several collections of art referred to as herbaria including an exhibit of plant-related pieces at Lytes Cary Manor House in Britain called simply Herbarium, as well as a book on art that links technology with plants, The Technological Herbarium (Gatti, 2010).

Right now it seems to be fashionable to use the word herbarium metaphorically in a variety of ways, usually relating to plants and collections and often with the idea of preservation, of memory.  This is especially true for writers interested in plants as sentient beings or at least worthy of more attention for having sophisticated interactions with the environment including with other living things.  It is not a coincidence that Giovanni Aloi, the author of the Lucian Freud book, is also the editor of a volume of essays, Botanical Speculations (2018), on plants in contemporary art with a focus on their “agency.”  There is also Botanical Drift: Protagonists of the Invasive Herbarium (Carroll, 2017), a collection of art pieces presented at the Royal Botanical Gardens, Kew that encouraged visitors to appreciate plants in new ways.

Michael Marder, a philosopher and leading figure in the “critical plant studies” movement to link the humanities to botany, has used the herbarium metaphor in two different ways in his books.  In The Philosopher’s Plant: An Intellectual Herbarium, Marder (2014) applies the term to emphasize his interest in collecting stories about how philosophers have incorporated their observations on plants into building their philosophical systems.  Marder’s The Chernobyl Herbarium (2016) is more personal.  It is a collection of writings about his memories of living downwind from Chernobyl at the time of the reactor accident and includes photographs of plants taken by Anaïs Tondeur by pressing plants from the area near the reactor onto photographic plates, which were thus developed by the radiation emitted by the plants.  The resulting images are ghostly but powerful.  Other meanings of herbaria also arise here including deterioration, death, and fragility.  Such metaphorical uses of the word may be one way we can give it more currency.  Max Black argues that metaphors can be used so much that they lose their force, but I don’t think we are there yet.

References

Aloi, G. (Ed.). (2018). Botanical Speculations. Newcastle upon Tyne, UK: Cambridge Scholars.

Aloi, G. (2019). Lucian Freud Herbarium. Munich, Germany: Prestel.

Arber, A. (1938). Herbals: Their Origin and Evolution a Chapter in the History of Botany, 1470-1670 (2nd ed.). Cambridge, UK: Cambridge University Press.

Axsom, R. (2005). Drawn from Nature: The Plant Lithographs of Ellsworth Kelly. New Haven, CT: Yale University Press.

Black, M. (1954). Metaphor. Proceedings of the Aristotelian Society, 55, 273–294.

Carroll, K. von Z. (Ed.). (2017). Botanical Drift: Protagonists of the Invasive Herbarium. Berlin, Germany: Sternberg.

Gatti, G. M. (2010). The Technological Herbarium (A. N. Shapiro, Trans.). Berlin, Germany: Avinus.

Livingstone, M. (1994). Jim Dine: Flowers and Plants. New York, NY: Abrams.

Marder, M. (2014). The Philosopher’s Plant: An Intellectual Herbarium. New York, NY: Columbia University Press.

Marder, M. (2016). The Chernobyl Herbarium: Fragments of an Exploded Consciousness. London, UK: Open Humanities Press.

Peitcheva, M. (2016). Charles Demuth: Drawings. Scott’s Valley, CA: CreateSpace.

Troyen, C. (1987). Charles Sheeler, Paintings and Drawings. Boston, MA: Little, Brown.

Art and the Herbarium: Galleries and Museums

Evil Flowers, National Gallery of Victoria

Anselm Kiefer’s Evil Flowers at the National Gallery of Victoria, Melbourne

Herbarium specimens are kept in many museums, museums of natural history, that is.  They almost never end up in art museums.  Almost never.  At both the beginning and end of his career, the German artist Joseph Beuys used pressed plants in his work.  Herb Robert (1941) is a notebook page with a list of medicinal plants in pencil and two dried and pressed flowers of Geranium robertianum pasted on top of the list.  Ombelico di Venere–Cotyledon Umbilicus Veneris (1985) is a series of ten pages of pressed specimens of Cotyledon umbilicus-veneris L. (now Umbilicus rupestris).  The first part of the title is the plant’s Italian common name, navel of Venus, for its navel-shaped leaves.  Beuys’s “specimens” are labeled with both common and scientific names and also where and when he collected them.  They may look like rather poor specimens made by an amateur, but they are considered works of art and have been sold separately to a number of collectors.  I don’t know how much they cost, but I suspect that I couldn’t afford one.  Beuys was influenced by, among others, Marcel Duchamp, who was famous for taking everyday objects like a urinal and exhibiting them as works of art, thus blurring the definition of art.

One of Beuys’s students, Anselm Kiefer, has used dried plants more extensively in his work, though not in ways as closely tied to herbarium specimens.  I first encountered his art years ago during a museum visit with my husband, who stopped in his tracks when he saw a Kiefer work.  I asked him why he was so struck by a painting that I saw as bleak and rather monotonous (you can tell which of us was an art historian).  Bob informed me that Kiefer was one of the great German painters of the post-World War II era, whose art addressed issues of that time.  I remembered the painting and the artist’s name, but I didn’t seek out his work.  Years passed, Bob died, I fell in love with herbaria, and on a trip to Melbourne, I saw Kiefer’s Evil Flowers (1985-1992) at the National Gallery of Victoria (see above).  Pasted to an oil painting, and almost completely obscuring it, were dried sprays of delphiniums covered in shellac.  Now I was stopped in my tracks.  These were not nicely pressed plants; they were brown and the flowers gone to seed.  But they were still tall and stately, though the title suggests an ominous story, as does much of his work.

For Kiefer, dried plants are not a matter of science but of metaphor.  He was born in Germany in March 1945, not surprisingly in an air-raid shelter.  He remembers thinking it normal as a child to play in piles of rubble (Dermutz, 2019).  But Kiefer’s work is not totally about destruction and death, it is also about memory and preservation.  He has a work called For Paul Celan – Ukraine (2005) that resembles an herbarium, a massive pile of lead sheets with aluminum sunflowers pressed between them, their flower heads and stems sticking out at each end.  It is as if the plants are struggling to leave the confines of the sheets and find the sun.  There is hope here, as in many of Kiefer’s works that incorporate sunflowers—real dried plants, real seeds, and painted or sculpted representations.  His work is complex, and though I’ve read some art criticism about him, I can’t say I understand it.  Yet I have come to appreciate it, be moved by it, and see the importance of dried plant material in artistic expression as well as in botanical science.

Another example of herbarium specimens in an art context is Tarin Simon’s Paperwork and the Will of Capital (2015).  This is a complex conceptual work in which Simon recreated bouquets decorating tables where important international agreements were signed, a political example of botany as interior decoration (see last post).  After taking a series of photographs of each bouquet, she pressed the plants from the arrangements and attached them to herbarium sheets, without labels.  She had sought technical assistance from the mounting staff at New York Botanical Garden.  For each bouquet/agreement, the photographs were stacked on top of pages from the treaty, along with a stack of the related herbarium specimens.  Each assemblage was presented in a glass case resting on a concrete plinth.  For Simon, this work was a commentary on how nature is used to support and display power, and her installation itself created a powerful statement when it was displayed at the 2015 Venice Biennial; quite a prestigious venue for herbarium sheets (Simon, 2016).

There are too many artists working with plant material in the herbarium tradition to mention them all here.  I’ll end with two who take very different approaches from the anthropological to the whimsical.  Lindsay Sekulowicz is an artist who had an exhibit at the Royal Botanic Garden, Kew in 2018 that included a selection of items from Kew’s economic botany collection.  Entitled Plantae Amazonicae, the show was made up of items that the 19th-century botanist Richard Spruce obtained from indigenous peoples of the Amazon.  It also presented some of the specimens he collected, including one of the tree Licania octandra, whose wood was mixed with river mud to make pottery.  Also dealing with material from the past, the artist Margherita Pevere found a folder with unmounted specimens that had been collected along the Croatian coast many years ago.  They had suffered insect and fungal damage, but Pevere felt this increased their visual and expressive interest so she mounted and labeled them.  She sees this collection as a memento mori for pondering issues of life and death, much in the style of Kiefer.

References

Dermutz, K. (2019). Anselm Kiefer (T. Lewis, Trans.). London, UK: Seagull.

Simon, T. (2016). Paperwork and the Will of Capital. Ostfildern, Germany: Hatje Cantz.

Art and the Herbarium: On and Off the Wall

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Herbarium display at London hotel coffee shop

In the last post, I discussed recent trends in botanical illustration, scientifically correct renderings of plants that can also be aesthetically magnificent.  Though he sometimes questioned its use, especially in writings on genera (Reeds, 2004), even Carl Linnaeus agreed about its beauty.  He papered the bedroom of his country home in Hammarby with hand-painted illustrations from Christoph Trew’s Plantae Selectae.  These were done by one of the greatest botanical artists, Georg Ehret.  While the prints are still in place, they pose a problem for art historians and restorers, as Per Cullhed (2008) notes in an essay written for a Linnean Society symposium marking the 300th anniversary of Linnaeus’s birth.  Restoration would be difficult because the paper has been severely damaged in places and may not survive an intervention.  However, doing nothing means that deterioration will continue.  Cullhen likens the problem to the dilemma of preserving Leonardo da Vinci’s The Last Supper without making it look very different from how it appeared before restoration.

Several years ago I wrote an article on the biology of interior decoration (Flannery, 2005), which, I argued, stems from biophilia, defined by E.O. Wilson (1984) as an innate urge to connect with other species.  Yes, this includes having house plants and owning dogs and/or cats, but it also means dried flowers—sort of a 3-D herbarium—and sitting on a couch with a floral chintz print.  Then there are the botanical prints that grace many people’s homes and seem to be perennial favorites.  Recently, I’ve seen a different though less widespread trend.  On my first morning in London on a visit in 2018, I planned to go to the Royal Botanic Gardens, Kew.  But first, of course, I needed breakfast.  As I sat down to order my coffee and scone, I was amazed to see an array of framed herbarium specimens on the restaurant’s wall (see image above).  It was quite a display, and on closer examination turned out to be from an unnamed collector who pressed them in Italy in the early years of the 20th century.  They made a beautiful display.  A friend told me of a restaurant in New York with a similar presentation, and The World of Interiors magazine featured the bathroom of a stately home with framed specimens hanging over the tub (Shaw, 2019).  I am of two minds about this trend, if it can be called that.  It does get herbaria seen by a wider audience, but unaccompanied by a museum-like descriptive card, viewers might not even realize what they are seeing.  The restaurant’s wait staff had never given them a second glance until I swooned over the display, and then they did look more closely, a tiny victory for the herbarium world.

Over the centuries, most people took a different approach to surrounding themselves with flowers:  they used wallpaper.  In the case of William Kilburn, a botanical illustrator for William Curtis’s Flora Londinensis, branching out into commercial floral designs for wall coverings and fabrics turned out to be more lucrative (Nelson, 2008).  He gave up the exacting scientific work, but his designs still revealed his attention to detail.  The 20th-century botanical artist Anne Ophelia Dowden also designed fabric.  In the 21st century, individuals sometimes moved in the opposite direction.  A number of those enrolled in the Certificate Program in Botanical Illustration at New York Botanical Garden were fabric designers who had lost work when the industry moved to digital art.

There is also another aspect of floral fabric design, and that’s the use of embroidery.  This is an old tradition that began with embellishment of religious vestments in the middle ages and then became common on the clothing of wealthy men and women and in home decorations.  This work was done by professionals, usually men, but then in the Renaissance, embroidery began to be taken up by upper-class women, with several pieces even attributed to Mary Queen of Scots (Parker, 1984).  Embroiderers used patterns books that were filled with floral illustrations to be copied onto fabric.  Jacques Le Moyne, who produced exquisite flower paintings, came out of the floral fabric design tradition of the French Huguenots.  A pattern book of plants and animals for embroidery was based on his work.

Today, there are a number of fiber artists who do beautiful floral embroideries, sometimes for high-end fashion designers, sometimes as works of art.  Karen Nicol’s work is one example of these approaches.  In addition, there is one artist whose work I find particularly intriguing because it is definitely in the herbarium tradition.  Susanna Bauer presses fallen leaves and then adds embroidery to them:  in some cases “repairing” insect damage with crochet, in others carefully adding stitches to the leaves without causing them to crack.  Her pieces definitely make the viewer look more carefully at the leaf.  They provide a different dimension to our relationship with nature, something more intimate than simply pressing plant material between sheets of paper.

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Sarah Herzog modeling the labcoat she embroidered for her graduate adviser, Dr. Maribeth Latvis

Other artists use machine sewing to represent plants in intriguing ways, such as Sumakshi Singh’s black thread sketches on thin fabric, creating a cloth herbarium collection of ethereal plant drawings.  In addition, there are two embroiderers whose work I found on Twitter.  One is the textile artist Charlotte Lade who volunteers at the herbarium of the Natural History Museum, London and creates work based on the specimens.  Also, Maribeth Latvis, who teaches at South Dakota State University and directs the Taylor Herbarium there, tweeted that her student had asked to decorate her lab coat and returned it festooned with embroidered flowers (see above).

References

Cullhed, P. (2008). The conservation of iconic objects and Linnaeus’ books and wallpaper. In The Linnaean Legacy (pp. 135–140). Linnean Society of London.

Flannery, M. C. (2005). Jellyfish on the ceiling and deer in the den: The biology of interior decoration. Leonardo, 38(3), 239–244.

Nelson, E. C. (2008). William Kilburn’s calico patterns, copyright and Curtis’s Botanical Magazine. Curtis’s Botanical Magazine, 25(4), 361–373.

Parker, R. (1984). The Subversive Stitch: Embroidery and the Making of the Feminine. New York, NY: Routledge.

Reeds, K. (2004). When the botanist can’t draw: The case of Linnaeus. Interdisciplinary Science Reviews, 29(3), 248–258.

Shaw, R. B. (2019). Tack’s exempt. The World of Interiors, April, 218–227.

Wilson, E. O. (1984). Biophilia. Cambridge, MA: Harvard University Press.

Art and the Herbarium: Botanical Illustrations

1 Rauh witch hazel

Watercolor of witch hazel seed pods by Dr. Dick Rauh, courtesy of the artist

Over three years ago, I began this blog with a series of posts on the relationship between art and herbaria (1,2,3,4).  This is such a rich subject that I want to return to it here and explore areas that I hadn’t discussed previously.  One topic is probably the most obvious and that’s botanical illustration.  Defined narrowly, this is art in the service of botany, documenting plants as accurately as possible either in pen-and-ink drawings or in watercolor.  These artistic traditions extend back at least to the mid-16th century, though there are accurate renditions of plants much older than that, for example in the sixth-century Juliana Anicia Codex, named for the Empress of the Holy Roman Empire, and the Carrara Herbal produced in Italy at the end of the 14th century.  The Linnaean era brought an informal codification of what a botanical illustration should include:  details of flower structure sometimes with dissections and enlargements as auxiliary to the main image, fruit might also be pictured (Nickelsen, 2006).  What didn’t change was the tradition of presenting a single species against a blank background, though in print, several individual species might be pictured on the same page to save space.

While some thought that photography would replace illustration in botanical publications, that substitution is hardly complete.  There is still a place for illustration in part because, as the zoological artist Jonathan Kingdon has noted:  “Contemporary research on the human brain shows that it does NOT process images as a neutral camera does.  The brain finds edges and builds constructions that are at least partially based on previous experience—possibly including past contacts with artifacts such as ‘drawings’ as well as previous knowledge of natural objects” (Kingdon, 2011, p. 137).  From this he concludes that:  “If the brain is unlike a camera in actively seeking outlines, there is a strong implication that ‘outline drawings’ can represent, in themselves, artifacts that may correspond more closely with what the brain seeks than the charts of light-fall that photographs represent” (p. 139).

Today, most illustrations are in pen and ink because watercolors are much more expensive to produce and publish.  However, in the late 20th and into the 21st century there has been a renaissance in botanical painting fueled by several factors.  Among these was the development of exhibitions and prizes.  The International Exhibition of Botanical Art & Illustration has been sponsored by at the Hunt Institute for Botanical Documentation in Pittsburgh since 1964.  This is a juried show with artists from many nations represented and is now usually held every two years.  The Royal Horticultural Society in London mounts a yearly Botanical Art Show and awards prizes in several categories.  I am proud to say that I’ve taken a number of classes with an artist who has been in the Hunt Show and also won RHS prizes.  Dick Rauh has taught for many years in the botanical illustration certificate program at New York Botanical Garden (NYBG) (see image above).  Such programs have done a lot to spur interest in botanical art and have produced many exceptional artists.  The best way to get a sense of the field is to look at the website of the American Society of Botanical Artists (ASBA), and at their journal, The Botanical Artist, which is full of wonderful articles about the field.

If there is one name that is synonymous with botanical art in the 21st century, it is that of Shirley Sherwood, who is not an artist but a generous patron of the field.  I first learned of her through her books on botanical art that feature pieces from her collection as well as other works (Sherwood, 1996, 2001, 2005).  These are fascinating to read, and her artistic taste is superb.  Sherwood has funded a gallery in her name at the Royal Botanic Gardens, Kew where contemporary botanical art as well as historical collections are exhibited.  Her husband James Sherwood, a well-known businessman, supports her interest in botany, and it’s a credit to them both that botanical art—and more broadly interest in plants—have flourished thanks to them.

Three other trends in botanical art worth noting include the focus many botanical artists have on picturing endangered species.  There have been several exhibits with this theme in botanical gardens in different countries, including one at NYBG sponsored by the ASBA.  Also, artists have been invited to participate in a number of florilegia projects.  Perhaps the best known was sponsored by Britain’s Prince Charles and focused on plants grown at his Highgrove estate.  His foundation also supported the publication of The Transylvania Florilegium picturing Romanian plants.  The Brooklyn Botanic Garden is continuing to sponsor its on-going project, a florilegium of plants in the garden.

The final trend I want to mention is the broadening of subject matter for botanical art.  Besides what would be considered traditional subjects and formats, some artists have been daring in taking on subjects such as dying and decaying foliage.  This may not seem particularly interesting, yet some of these pieces are remarkable, such as the work of Jessica Shepherd.  Not only are they beautiful, but they focus attention on a portion of the plant life cycle that we often neglect.  A decaying leaf with its myriad colors and lacy structure is a wonder that we usually just rake up and throw in the compost pile.  Also, more botanical artists are taking on ecology by presenting plants in context, as they grow in nature.  Margaret Mee, the British artist known for her works on the Brazilian flora, was a master of this genre but many others use this approach such as Jenny Hyde-Johnson of South Africa.  In other words, there are more and more wonderful things to look at in the botanical art world.

References

Kingdon, J. (2011). In the eye of the beholder. In M. R. Canfield (Ed.), Field Notes on Science and Nature (pp. 129–160). Washington, DC: Smithsonian Institution Press.

Nickelsen, K. (2006). Draughtsmen, Botanists and Nature: The Construction of Eighteenth-Century Botanical Illustrations. Springer.

Sherwood, S. (1996). Contemporary Botanical Artists. New York: Cross River Press.

Sherwood, S. (2001). A Passion for Plants: Contemporary Botanical Masterworks. London, UK: Cassell.

Sherwood, S. (2005). A New Flowering: 1000 Years of Botanical Art. Oxford, UK: Ashmolean.

Opening Up Herbaria: Higher Education

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Website for BLUE: Biodiversity Literacy in Undergraduate Education

When I majored in biology in the late 1960s, the focus was on cellular biology.  Our year-long intro biology course concentrated on molecules, cells, genetics, and human physiology.  Taxonomy was almost completely skipped over.  This was probably worse than eliminating it completely because a quick tour was head-spinning, and we were left with little more than the idea that the living world is full of exotic creatures with tongue-tying names, definitely an aspect of biology to avoid.  During the fall semester, I fell in love with electron microscope images of cells and that set my educational course.  If I could see a living thing, I wasn’t interested in it.  Out of fifteen biology majors in my cohort, only one went into organismal biology, becoming an oceanographer studying copepods.

While many of my generation continued on to careers in ecology, few ended up in systematics, and the movement away from this discipline remains a trend to this day.  The result is that there are not many botanists and zoologists who have expertise in accurate species identification.  This is particularly ironic because species are still being discovered.  However among plants, a quarter are left undescribed for 50 years or more after they were first found (Bebber et al., 2010).  With the dawn of the 21st century, targeted efforts have been underway to bring back what can broadly be called natural history:  studying biology at the organismal level.  In part this trend is the result of the massive NSF project over the past 10 years to work toward digitizing information on the nation’s natural history collections.

As collections are scrutinized, many discoveries are made, and just the scope of the collections has reawakened interest in them, in what they say about the natural world.  The Society of Herbarium Curators is playing a larger and larger role in this work, as it encourages interest in herbaria among many constituencies, including young people considering careers in systematics and botanical biodiversity.  One of the more disturbing discoveries is the number of species known from old collections that haven’t been found again in the 20th and 21st centuries.  Another is that scientific species names are a foreign language for most of us.  I definitely include myself here.  Until I got on my botany kick, I knew more bacterial than plant genera.  Catching up isn’t easy but it feels good when I can identify a species and name it correctly.  And it’s that good feeling, among other things, that botanists are attempting to pass on to more of today’s students.

In the last post, I wrote about bringing natural history into K-12 classrooms.  Here I want to mention programs to do the same in higher education.  This is a huge topic because it has several different strata.  Among undergraduates, there are some who will major in biology and go on to work in ecology, systematics, and related fields.  But the vast majority will not.  These are the students I taught and that I still worry about.  If they are interested in anything biological, besides issues of health, it is organisms they can see.  Yet much of biology education is devoted to cells and molecules.  The first semester I taught I was shocked to find that my nonmajors did not find protein synthesis fascinating, and they still don’t.  I tried to find ways to make it tantalizing, and finally turned to dealing with another problem:  plant blindness.  I found this an easier sell.  Students were much more likely to find trees on campus to observe than to stumble on a ribosome.  There are now many natural history activities geared to such students including a project developed at the Université catholique de Louvain that could be adapted in many ways.  In addition, Brad Balukjian has written persuasively on why he has just begun a natural history and sustainability program at a California community college.

For those majoring in biology, there is definitely an upswing of interest in fields focused on biodiversity.  The NSF-sponsored program, BLUE: Biodiversity Literacy in Undergraduate Education, aims at developing a set of biodiversity competencies for undergraduates.  These would include not only a focus on organismal biology and ecology, but also on digital literacy and bioinformatics, which will be essential for future professionals.  It is exciting to see a field form around these ideas, some of which are centuries old, and some only beginning to gel.   Natural history collections are essential to these efforts because they hold a great deal of the history of the natural world.  They are also where the living world of today will be recorded.  As I have mentioned a number of times, I volunteer at the A.C. Moore Herbarium at the University of South Carolina, Columbia.  It is alive with undergraduate students who as student workers and interns have learned a great deal about botany by digitizing label information and imaging specimens.  Among the specimens are those collected in the mid-19th century by the planter and botanist Henry Ravenel.  These are on permanent loan from Converse College, and provide a picture of the flora of South Carolina of the past.  There are also graduate students in environmental studies who are contributing specimen vouchers from their work in the field.  Herrick Brown, the A.C. Moore Curator, whose doctoral work dealt with seed dispersal and climate modeling (Brown & Wethey, 2019), has plans to foster participation by more students in the herbarium’s activities.  It is an exciting place to be!

References

Bebber, D. P., Carine, M. A., Wood, J. R. I., Wortley, A. H., Harris, D. J., Prance, G. T., … Scotland, R. W. (2010). Herbaria are a major frontier for species discovery. Proceedings of the National Academy of Sciences, 107(51), 22169–22171.

Brown, H. H. K., & Wethey, D. S. (2019). Observations on anthesis, fruit development, and seed dispersal in Gordonia lasianthus (theaceae). Journal of the Botanical Research Institute of Texas, 13(1), 185–196.

Opening Up Herbaria: K-12 Education

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iDigBio resource page for K-12 education

As I mentioned in the last post, many of those responding to herbarium outreach programs are senior citizens with time and expertise to share.  As a member of this population I obviously consider their contributions significant.  But let’s face it, we are short-term participants in the herbarium renaissance.  To build a firm foundation for the herbaria of the future, young people’s interest must be captured and nurtured.  In my post on outreach, I mentioned a number of clever ways herbaria, botanic gardens, and natural history museums are luring youngsters into the world of plant preservation and conservation.  In this post, I want to look at programs to integrate natural history into the K-12 curriculum.

For obvious reasons, animals are often the focus of natural history education.  I am hardly going to dis an entire kingdom, especially because many botanists tell of being fascinated by bugs, snakes, or small rodents when they were young.  Hunting for these eventually led them to see the plants that many animals call home.  At this point, plant blindness has almost become a cliché in biology, though I think it is still real, at least among adults.  Children are physically closer to the ground and therefore to the world of plants, and this is one reason that early education about plants makes sense (Sanders et al., 2014).

I also think that simple is better.  The artist Georgia O’Keeffe became fascinated by flowers when she was seven years old, when a teacher distributed tulips to examine.  It opened a new world for O’Keeffe and led to her amazing floral works.  When I was a freshman in high school, where I had my first exposure to real science education, our teacher sent us home for spring break with the assignment to simply notice the changes of spring.  This was memorable for me in part because it wasn’t “real” homework:  no reading or writing required.  But what really struck me was how much there was to see:  tulips opening with so much inside each bloom that I had never noticed before, buds on trees, weeds springing up in sidewalk cracks.  I didn’t become an artist because of this experience, but I did realize that close observation was fun; this might have been the start of my becoming a biologist.

To bring herbaria into this, I think pressing plants is a great way to observe them.  The first step is selecting a specimen.  This means looking for a good candidate:  are there flowers or berries, is this a representative sample?  Just looking might lead to discovery of more traits like tendrils, or hairs on the leaves, or small features of the flower.  Then wrestling the specimen into place on a sheet of newspaper so it presses well can lead to other discoveries, such as the thickness of the fruit or how easy or difficult the stem is to bend.  In other words, collecting leads to knowing a plant, having a tactile relationship with it as well as a visual one.  There might even be scent involved.  Yes, the specimen does need to be identified and labeled, but this should be done with gentle encouragement rather than as a hurdle to be overcome or a quiz to be passed.

I am not arguing that children’s exposure to nature should be just about observation and nothing more, but I think direct experience should definitely be at the core of any exercise.  The University of Reading recently staged a day-long symposium called “The Big Botany Challenge.”  There were 80 participants from 50 different schools, botanic gardens, research institutions, conservation organizations, etc.  By the end of the day, the room was abuzz with ideas that had been shared among the presenters and other participants.  One speaker, Nigel Chaffey, advocated for “botany by stealth.”  Since many students aren’t interested in plants, he asks:  “Why not smuggle bits of plant information into lessons on geography, history, art and computing?”  Coincidently, I recently heard Rudy Mancke, the naturalist in residence at the University of South Carolina, Columbia, make a similar suggestion, but for a different reason.  He argued that since humans are part of nature, every subject is related to it:  the natural world is the thread the runs through all disciplines, and they should be taught with this in mind.

Because interest in natural history education is rising, there is a wealth of information on the web to guide teachers.  It is ideal if projects deal with plants from nearby areas.  It’s difficult for students to relate to a tropical plant if they are living in Maine, in the sense that their learning won’t be reinforced by coming upon such plants in the outdoors.  There are several sites that offer diverse activities, such as iDigBio in the United States and the Big Botany Challenge in Britain.  Canada has the Children and Nature Network and Australia has activities through its Atlas of Living Australia.  While the plants may be different in far-off lands, the activities may provide novel ideas that could be adapted to any ecosystem.

I want to end this post with a niggling thought from the very back of my mind.  A number of historians of natural history, including Lynn Barber (1980), argue that the 19th-century rage for natural history started to dim when the subject began to be taught in schools.  Then it became work.  While I don’t think this means that natural history should not be a part of a student’s education, it should cause teachers to think twice before making forays into nature too focused on standards and not on joy.

References

Barber, L. (1980). The Heyday of Natural History. Garden City, NY: Doubleday.

Davies, P., Sanders, D. L., & Amos, R. (2014). Learning in cultivated gardens and other outdoor landscapes. In C. J. Boulter, M. J. Reiss, & D. L. Sanders (Eds.), Darwin-Inspired Learning (pp. 47–58).

Opening Up Herbaria: Citizen Science

2 Notes from Nature

Notes from Nature website with herbarium transcription projects

It’s almost 10 years since I first read about citizen science in an article by Amy Mayer (2010) on amateur naturalists recording phenology information.  I tucked the idea away as interesting, since I taught nonscientists and saw this as a possible way to engage them in observation.  Today, with citizen science being a buzzword in the natural history collection community, it’s difficult to image that it could have been a novel idea in the recent past (Flannery, 2016).  Mayer writes that the term was probably first used by Cornell University’s Laboratory of Ornithology for projects tracking bird populations.  Ornithology has a strong tradition of respecting and using amateur expertise, but now this approach has spread much more broadly.

At the last iDigBio research conference, there were many references to the use of iNaturalist data in studies on phenology and species distribution.  iNaturalist is a robust platform that allows participants—and anyone can become a participant by registering—to record their observations.  Many use their cell phones or other mobile devices to provide images as well as identification and location information.  There are now so many individuals entering data that researchers can have confidence in this information.  In order to build community, participants can create local groups and share findings in a new form of the natural history societies that were common at the end of the 19th century (Barber, 1980).  In fact, there is an aspiration that iNaturalist and other such sites can lead to a new flowering of natural history, with appreciation for biodiversity and its conservation as central to this trend.  The National Ecological Observatory Network (NEON) has organized a number of these projects.

Another major digital tool that also deals with natural history data and relates directly to herbaria is Notes from Nature, a segment of Zooinverse, which describes itself as “People Powered Research” and hosts projects in many scientific areas.  Notes from Nature is a platform where users can participate in projects to, for example, digitize the information on specimen labels.  On the website there are links to assignments from a variety of different institutions; these can involve anything from insects to salamanders to plants.  In fact, the preponderance of these tasks deal with plants and with transcribing specimen labels.  Right now there are projects listed about plants from the Southeast, California, and Florida.  New York Botanical Garden and Missouri Botanical Garden both have global projects, with NYBG’s focus on historical records.  Just think, anyone anywhere can look at beautiful specimens and transcribe them, thus aiding science and satisfying an urge to know more.  Many herbarium curators have noted that their projects are often completed quickly.  Notes from Nature and comparable sites like the Australian DigiVol have mechanisms for checking the data so the information that’s actually uploaded to portals such the Australasian Virtual Herbarium for Australian and New Zealand herbaria, CCH for California herbaria, and SERNEC for southeastern US herbaria are accurate.

There are also many other ways to get involved in digital endeavors.  The Smithsonian Institution has a transcription center that provides access to tasks dealing with several of their collections, including the field notes of scientists affiliated with the National Museum of Natural History.  The Field Notes Project, a collaboration between the Smithsonian and Biodiversity Heritage Library (BHL), has been going on for a number of years.  Its results are now available through BHL, which also has other citizen science projects including ones dealing with annotating the thousands of images available through BHL and its Flickr site.  The latter is a wonderful place to visually wander when in need of inspiration or of an aesthetic lift.

I have emphasized sites in the United States, but Citizen Science is a global phenomenon.  The British have herbaria@home and the French, Les Herbonautes.  Besides transcription efforts, there are many environmental monitoring projects, including ones in Japan to measure the continuing radiation effects of the reactor damage at Fukushima after the Tohoku earthquake in 2011 (Irwin, 2018).  In Belgium there has been a collaboration to monitor air quality; about 20,000 people signed on, each paying ten Euros to do so.  The logic for this is that participants would be more committed to sending data if they have an economic stake.  The ubiquity of cell phones makes it possible for even those in less developed nations to become involved, and researchers are encouraging participation in a number of agricultural as well as biodiversity initiatives.  Some worry about the validity of the data and what if anything can be extrapolated from it.  However, the citizen science model, as it is refined, could provide a wealth of important information for science in the future, while also building a more science-engaged public.

Many types of citizen science are sources of free labor for natural history collections.  The large number of senior citizens around at the moment contributes one important pool, and young people doing service projects and internships represent another.  I should also note that such projects compose a small portion of the Citizen Science landscape that also encompasses special interest groups involved in environmental issues and conservation.  Others deal with medical issues.  Broadly, Citizen Science is about members of the public wanting to be involved in scientific issues in order to understand them better and to have their voices heard.  As a citizen scientist transcribing specimens at the A.C. Moore Herbarium at the University of South Carolina, Columbia, I can attest to it being a great way to become part of the natural history enterprise.

References

Barber, L. (1980). The Heyday of Natural History. Garden City, NY: Doubleday.

Flannery, M. (2016). Citizen science helps botany flourish. Plant Science Bulletin, 62(1), 10–15.

Irwin, A. (2018). Citizen science comes of Age. Nature, 562, 480–482.

Mayer, A. (2010). Phenology and citizen science. BioScience, 60(3), 172–175.

Opening Up Herbaria: Outreach

1 RBHE Frankenstein

“Frankenstein” specimen created at Halloween 2019 event at the Royal Botanic Garden, Edinburgh

One reason I stay fascinated by herbaria is that they are changing so rapidly; there is always something new to discover, especially with the continuing digitization of collections, but there are a number of other intriguing trends as well.  Herbaria are becoming more present on social media, making it easier to find out what’s going on.  I have never gotten hooked on Facebook, but I am a devoted Twitter user, more a reader than a tweeter.  I can’t say that I follow a huge number of herbaria, but I’ve come to enjoy several run by dynamic curators; Mason Heberling (@jmheberling) at the Carnegie Natural History Museum, Jordan Metzgar (@MasseyHerbarium) at Virginia Tech, and Jessica Budke (@UTKHerbarium) at the University of Tennessee, Knoxville are among these.  Heberling and his coauthors have written a seminal paper tracking the changing uses of herbarium data in journal articles.  He also frequently tweets about a specimen collected “on this date” from the Carnegie Museum Herbarium’s rich collection.  Metzgar is energetic in luring students and the general public into the Massey Herbarium through a variety of activities, including making plant-related Lego models.  Budke lets her students do most of the tweeting, and they write about collecting trips and events like Tea and Scones in the herbarium as ways to lure their fellow students to a place that has become important to them.

Anyone interested in herbaria knows that most people are not, and that’s a problem.  Herbaria are by definition full of plants, so herbarium blindness is just one more aspect of plant blindness.  And herbarium blindness can lead to herbarium closures.  The curators I’ve just mentioned are aware of this, and they are using a number of tools, including Twitter and other social media platforms, to make not only the existence but the value of their collections known.  Many herbaria now have short videos telling about what a herbarium is and why theirs is particularly interesting.  They range in tone from informative to fun, and target various audiences, including children.

The idea of children running around a herbarium might make some systematists cringe, but if young visitors are engaged in activities, such experiences can be memorable and bode well for the future of botany.  In some cases, the events aren’t in the herbaria, but in other venues on site.  A number of botanical gardens and herbaria have staged Harry Potter related events, with presentations on the plants mentioned in the books.  Other activities include making herbarium specimens, from simple pasting specimens on paper for children, to adult classes on how to mount, label, and georeference specimens that could be added to a scientific collection.  Different lures attract different groups.  Sometimes, adult participants become captivated enough to volunteer as specimen mounters or digitizers.  Children might have had so much fun that they can’t wait to go back to the garden or museum.  In every case, participants know more about herbaria than they did before the event.

Craft activities are also used to spread the word about herbaria.  For Halloween, the Royal Botanic Garden, Edinburgh advertised:  “Come along this weekend & create a “Frankenstein” specimen with the RBGE herbarium team part. This event is fun crafts, then digitize your creation (+ a touch of info about our specimens & herbaria). Suitable for all ages.”  The image above is a sample of what they had in mind.  I think the “specimen” digitization is a nice feature.  Georgia Southern University’s herbarium tweeted recently that they use leftover plant material that doesn’t get mounted in paper craft projects, reminiscent of the tradition of making arrangements of pressed flowers simply for their beauty rather than as scientific specimens.  This is an old craft that can be directly related to plant knowledge.  As a useless piece of information, Grace Kelly, the actress and Princess of Monaco, made pressed flower arrangements and wrote of how much she learned about plants in pursuing this hobby (Robyns, 1980).

Traditionally, curators have given limited tours of herbaria, though these are of necessity restricted to small groups because of space constraints.  However, tours and open houses are becoming more common, and there are other forms of publicity as well.  At the A. C. Moore Herbarium at the University of South Carolina, Columbia where I volunteer, the curator Herrick Brown and the curator emeritus John Nelson lead monthly botanical tours of the “Horseshoe” the historical center of campus that boasts an array of beautiful trees and shrubs.  They also speak to conservation groups and garden clubs whose members may then follow-up by visiting the herbarium.  I have even seen John Nelson strike up a conversation with two parents visiting USC who asked for directions.  He got them geographically oriented, and then invited them to see the herbarium, after he told them what it was.  With time on their hands, they agreed, and thus John served as an ambassador for the university and for botany.  Now that’s outreach.  John Nelson is also the originator of the bumper sticker “it’s not HIS barium. . .”  Perhaps the best indication of his interest in getting out the word is that the URL for the USC herbarium is www.herbarium.org, which he was foresighted enough to acquire very early in the internet’s history.

Outreach is also related to the other topics I’m covering in this series of posts—citizen science, k-12 education, and higher education—as herbaria are involved in all of these endeavors.  The next post will be on citizen science, an exciting topic in itself, and even more so when the science deals with specimens.

Note:  I want to thank John Nelson and Herrick Brown for welcoming me into the A.C. Moore Herbarium and patiently answering my many questions.

References

Heberling, M., Prather, L. A., & Tonsor, S. (2019). The changing uses of herbarium data in an era of global change. BioScience, 69(10), 812–822.

Robyns, G., & Grace, P. of M. (1980). My Book of Flowers. Garden City, NY: Doubleday.