Plants in Sweden: Specimens and Photos

2 Gothenburg BG

Gothenburg Botanical Garden, September 2017

As I wrote in my last post, I recently spent a week in Sweden at a planning meeting for a grant on increasing people’s awareness of plants.  Among those I met was Eva Nyberg, a senior lecturer in biology in the Department of Pedagogical, Curricular and Professional Studies at Sweden’s University of Gothenburg.  When she learned that I was interested in herbaria, she mentioned her surprise at discovering that when another professor took over a course that she had taught and had always included students’ collecting plants and making herbarium specimens, they were now taking photographs of plants rather than collecting specimens.  She thought there was something lost in this shift and I totally agree.  Here I want to discuss what’s lost, which I think is considerable.  However, in the interest of full disclosure, I also have to admit that during my Scandinavian visit, I took many photos of plants, especially to record what I saw in botanic gardens (see photo above), and I produced no herbarium specimens.  Of course, I didn’t have permission to collect nor to bring foreign plant material back into the US.  But leaving that out of the picture, it is also much less time consuming to take a picture, even though I was careful to label each, something I wasn’t so conscientious about than in the past.  I also made a few sketches, a much slower process, but one that requires more observation and therefore more learning and experiencing of plant form.

When it is possible to make specimens, it’s an experience that isn’t replicated by photography or drawing.  A student has a very different physical relationship with a plant in taking a photo of it versus making a specimen of it.  The latter is a far richer way of knowing the plant.  Photography is about distance, about not getting too close to the subject, and it really doesn’t make much difference what the subject is, almost anything can be photographed.  Not everything can be preserved by being pressed between sheets of newspaper.  Also, the physical contact with the plant provides much sensory engagement:  the smell of leaves and flowers, the sticky or velvety or prickly feel of stems, the snap sound of breaking off a dry branch.  What I am talking about is the materiality of the plant, and materiality of almost everything is something we tend to take for granted or neglect to appreciate, especially in our increasingly virtual world.   There is also the process of selection: what is to be collected, what constitutes a good specimen  Yes, selection decisions are also made in taking a photo—angle, proximity, inclusiveness—but these decisions are often done in a matter of seconds and usually don’t involve as much physical rummaging amid the plant material.

Then there is the crucial tactile process of arranging the material for pressing.   This requires a combination of knowledge of what needs to be displayed and of how this particular specimen responds to manipulation, as well as manual dexterity in setting all parts of the specimen in place.  Though an important skill, such manual work is less and less common today.  An art professor I know bemoans the fact that art students come to college much less adept at the physical manipulation of materials than they were in the past.  If art students are deficient, where does that leave students in less hands-on fields?  Then there is all the work involved in arranging the dried specimens on a sheet, labeling them properly, and gathering stray material in a small envelope attached to the sheet.  When I made my first specimen labels I felt a sense of responsibility that I don’t feel when I name a photograph.  The label seems a more public record, something that could last a long time and be seen by many eyes, something with my name attached.  The metadata is not just virtual as it is with a digital photo, it’s right there in black and white.

I would also argue that there is a greater sense of accomplishment in producing five or ten herbarium sheets compared to five or ten photographs of plants.  Again, there is the physicality which is more multifaceted than are photos, even if printed.  Also, in many cases, the specimens, if they are well done, are added to the permanent collection of the institution’s herbarium.  In digitizing specimens at the University of South Carolina’s A.C. Moore Herbarium, I often come across specimens that were created by students 10 or 20 or more years ago.  I assume they are students, because the collection numbers are in the single digits.  They many not have gone on to further work in botany, but they have left a permanent record at their alma mater.

There is one more issue I want to mention:  pressed doesn’t mean totally two-dimensional.  Flattened specimens still have depth and texture, they give a much better sense of the materiality of a plant than any photograph could (Flannery, 2012).  They almost invite inspection because of their physicality.  They have more of a presence than a photograph does.  This is something that a student might not be fully aware of, but nonetheless, it has a subliminal effect on their experience of the plant.   That was what was at the heart of my conversation with Eva Nyberg:  how to most effectively engage students with plants, and the more multisensory experience involved, the better.  In my next post I’ll continue with this theme.


Plants in Sweden: Specimens and Art

1 Santalum

Specimen of Santalum fernandezianum from the University of Gothenburg Herbarium

In September I spent a week at the University of Gothenburg in Sweden.  I participated in planning meetings for a project called Herbaria 3.0, which I’ll describe in the last post in this series.  But first I want to delve into some of the plants and people I met along the way.  On my first day in Gothenburg, I caught up with two members of our group.  Terry Hodge is a graduate student in the horticultural program at the University of Wisconsin, Madison, where his research deals with tomato breeding.  Dawn Sanders is a senior lecturer in the Department of Pedagogical, Curricular and Professional Studies at the University of Gothenburg and the lead researcher on a project called “Beyond Plant Blindness: Seeing the Importance of Plants for a Sustainable World.”  This was an interdisciplinary endeavor focusing on student teachers’ perceptions of plants and on finding ways to foster appreciation of the importance of plants for a sustainable world.

One aspect of the project involved the Gothenburg Botanical Garden where we headed to meet Claes Gustafsson, the curator at the University’s herbarium which is housed adjacent to the garden.  The collection has about 1.6 million specimens, though as with most large herbaria, the exact number is still unknown.  The type specimens have been scanned and digitized as part of the Global Plants Initiative and are available on the web through JSTOR Global Plants and also at Sweden’s Virtual Herbarium.  The herbarium also includes specimens from one of the most noted botanists at Gothenburg, Carl Skottsberg (1880-1963), who founded the herbarium and who collected in Antarctica and South America as well as in the Pacific, including on the Hawaiian Islands and on Easter Island.

Dawn Sanders asked Claus if he had any good plant stories to share about the specimens in the collection, since the focus of our project is on stories that link plants and people.  It only took Claus a minute to decide on what he wanted to show us.  He produced a specimen of a tree in the sandalwood family, Santalum fernandezianum F.PH., which is now extinct but was collected in 1908 by Skottsberg on Más Afuera, one of the Juan Fernandez Islands, where Robinson Crusoe was set (see photo above).   The tree was native to these islands off the coast of Chile, and this specimen is from the last known tree of that species.  It was the only one left on the island and none have been found since.   Claus showed us the article Skottsberg wrote about his visit and about the tree; he was also able to find the original photograph used in the article, and a slice of wood taken from a dead branch of the tree (See photo below).  The wood, with the species name scrawled in pencil across it, has a label attached and still retains a little of the sandalwood scent even though the hook protruding from it suggests it hung in Skottsberg’s office for many years.  Claus mentioned that Skottsberg was well known among Hawaiian botanists because of his work on those islands, and I have found a book he wrote that was translated into English, The Natural History of Juan Fernandez and Easter Island.  We left thinking that the sad story of the Juan Fernandez sandalwood would definitely be highlighted in our project.  Discovering a story like this is what I love about visiting a herbarium.  And I’m sure that Claus could have shared many more if we had had the time.

1b Santalum wood

Slice of S. fernandezianum wood from the University of Gothenburg Herbarium

After our meeting, we stayed at the garden to see parts of an art installation done by Bryndis Snaebjörnsdóttir and Mark Wilson.  There were three separate elements, in three different areas of the garden.  Unfortunately, we arrived at the tail end of the exhibit, and one part had already been dismantled.  It was an eight-meter long tapestry depicting a scanning electron microscope (SEM) picture of a Stipa pennata seed, a long graceful structure adapted to be wind dispersed.  I would have loved to have seen this work because it was made from an image constructed with 26 separate scanning electron microscope (SEM) scans.  At the reception building was the second part of the exhibit, a series of SEM scans of the seeds of 14 other species.  In the background of each was a grayed-out photo of the plant itself, and beneath the scan, a description of the plant written by a long-time Gothenburg gardener.  The artists’ aim was to help the viewer see plants in a different way, to focus on the seed when usually the adult plant is what’s most apparent.  To further illustrate the connection between the two, the exhibit also included pots where seeds of each species were grown, some more successfully than others.  The exhibit’s third part was further into the garden, and on the way we passed the garden’s café where Dawn introduced us to the Swedish custom of Fika, or an afternoon snack, of which we all approved.  That readied us for the climb to a wooden shelter where two photographs of a field of wild flowers including Stipa pennata had been printed on Plexiglas and mounted in the open areas of the shelter (see photo below).  Outside there was also a patch of the grass growing so a visitor could experience the same plant in different ways.

1c Wildflower installation at Gothenburg BG

Installation by Bryndis Snaebjörnsdóttir and Mark Wilson at the Gothenburg Botanical Garden

This garden tour was a wonderful way to prepare for the work on our project.  We had experienced plants in many different ways—as dried specimens, as art, and as living beings.  The visit also gave us a taste of what Dawn’s plant blindness project was aiming to achieve, and what our project could add to that effort.  In my next post, I will write about another biology educator at the University of Gothenburg and our discussion of herbarium specimens.

Books Old and New, Part 4: Gods of Nomenclature

4 Gods

University of Chicago Press, Chicago. (2008)

As I was packing books for my move, which was the impetus for this series of posts on books (1, 2, 3) I’ve acquired in the past and more recently, I came across excellent books by the St. Louis University botanist, Peter Bernhardt.  The first was Wily Violets and Underground Orchids (1989) that drew on his general knowledge of botany and also on his orchid research, particularly in Australia.  Then came Natural Affairs (1993) on relationships between plants and humans and The Rose’s Kiss (1999) that dealt with flower structures and how they function, particularly in luring pollinators.  All these books made the cut and are now safely on bookshelves in my new home, though I couldn’t tell you their precise location—there is little order to the collection at the moment.

The latest Bernhardt book for the general reader is God’s and Goddesses in the Garden: Greco-Roman Mythology and the Scientific Names of Plants (2008).  This too made the trip and is the one I most wanted to reread.  I’ve done that now and want to share some of its gems with you.  This is probably the most technical of Bernhardt’s books because of its topic.  In order to make his point that the names of plants are in many cases as fascinating as the organisms themselves, he introduces the basics of taxonomy and botanical nomenclature—and of mythology as well.  Because he is such a good writer, Bernhardt does this admirably.  I may be prejudiced in his favor since he begins the first chapter with a section called “Inside the Herbarium.”  He starts with a passage from Ovid’s Metamorphosis in which the poet quotes the one-eyed mythic monster the Cyclops on the fruits growing in the garden and why it’s impossible to give precise scientific names to some of them, particularly the plums.  It would be necessary to have more information, and ideally a voucher, a herbarium specimen of the plant cited.  That’s Bernhardt’s clever segue into the importance of scientific names as the only way to be sure of what a writer is really talking about.

Next comes, not surprisingly, a section on Linnaean nomenclature, where Bernhardt not only explains the basis of binomial nomenclature and why it was so needed, but also describes how Carl Linnaeus is responsible for so many of the mythological plant names.  Linnaeus was not exactly a new Adam, although he has sometimes been described this way.  While every scientific plant name used today dates from 1753, the date of publication of his Species Plantarum, or later, he didn’t begin with a totally clean slate.  He adapted many plant names that had long been in use, which is why names in 16th and 17th-century herbals often seem familiar.  However, he still had to supply many new genus names, and for this he chose to rely on Greco-Roman mythology.

Where plant names come from is the subject of Bernhardt’s second chapter.  He begins with the easiest category, plants named after people, real people not mythological ones.  Some genus and particularly species names are given to honor a noted botanist, though at times the honor is bestowed on a statesman, a spouse, or even a celebrity:  Lady Gaga has a fern genus named after her.  Also common are species names derived from geographical locations where the plant was found.  Then there are the descriptive names, telling something about the plant, such as that it has glossy leaves or a large flower.  While these may be used for either genera or species, most classical names designate genera.

How did Linnaeus choose names from myth?  The answers provide the heart of Bernhardt’s book.  After the two introductory chapters, he starts each of the following with a brief exposition of a classical myth, including the names of the characters and what happens to them.  Then he describes how these names have ended up associated with plants.  He begins with the Greek creation myth related by the poet Hesiod in which day and night are given names, with night called Nyx.  This explains Nyctaginia or night blooming flower and Nyctocalos, beautiful at night.  In some cases the names have less straightforward allusions, as with the banana genus Musa.  This is an Asian plant, but it was Arab traders who brought it to the West, and Linnaeus is referring to that connection in the name.  Also, Muslims call bananas trees of paradise, so Linnaeus named the common banana of the time Musa paradisiaca and even wrote a book about it in 1736.  In regaling the reader with these stories, Bernhardt notes that some of the most intriguing names are no longer botanically accurate because of nomenclatural changes.  Since many of these names were given by Linnaeus, it stands to reason that over the years more and more of them will fade due to name changes for taxonomic reasons, despite their beauty and ingenuity.

This is a book that is best dipped into rather than read straight through.  It’s extremely rich in names, stories, and plant information, and might cause intellectual indigestion if experienced in high doses.  However, for anyone who loves plants, it’s definitely worth reading because it fosters an appreciation for botanical nomenclature which often seems unwieldy to say the least.  Bernhardt’s book may even drive you to other sources on the subject such as Stearn’s Botanical Latin (1992) and Lorraine Harrison’s Latin for Gardeners (2012).


Bernhardt, P. (1989). Wily Violets and Underground Orchids. New York: William Morrow.

Bernhardt, P. (1993). Natural Affairs: A Botanist Looks at the Attachments between Plants and People. New York: Villard.

Bernhardt, P. (1999). The Rose’s Kiss: A Natural History of Flowers. Chicago: University of Chicago Press.

Bernhardt, P. (2008). Gods and Goddesses in the Garden: Greco-Roman Mythology and the Scientific Names of Plants. New Brunswick, NJ: Rutgers University Press.

Harrison, L. (2012). Latin for Gardener’s. Chicago, IL: University of Chicago Press.

Linnaeus, C. (1736). Musa Cliffortiana. Leiden, The Netherlands.

Stearn, W. T. (1992). Botanical Latin (4th ed.). Portland, OR: Timber Press.

Books Old and New, Part 3: Irish Natural History

3 Ireland

McGill-Queen’s University Press, Montreal, Canada (1997)

This series of blog posts (1, 2) is called “Books Old and New” because I’m covering some that I read years ago and others that are recent publications.  A book that was published 20 years ago, but is new to me is Nature in Ireland (Foster, 1997), a collection of essays that runs the gamut from geological history to present-day issues in forest conservation.  There is botany here, but I didn’t read this book primarily for that, but rather because I am attempting to finally get to know my parent’s native land from the biological perspective.  I’ve been steeped in its culture and history from birth, and since my mother did win a school prize in botany, I learned something of its plant life.  However, this mostly amounted to her complaining about plants that grew well in Ireland, such as primroses, but had to be coaxed in hotter and drier New York.

My mother learned in school that the Irish terrain resembled a soup bowl in that most of the mountains were along the coast with flat plains in the center.  Nothing is that simple, of course, but the first essay, “The Testimony of the Rocks” by John Feehan explains why this is so.  Feehan does a good job of illustrating how the Irish landscape came to be, and why the land in many areas is so rugged and filled with limestone.  His work is a good reminder that in order to understand plants, it’s necessary to understand the substrate on which they grow.  The most intriguing thing I learned here is that oldest known land plant, Cooksonia, can be found in Silurian fossils (428 Ma) from Devil’s Bit Mountain, a name I remember because my grandmother came from near there, and my mother explained that the gap in the mountain was said to be caused by the devil taking a bite out of it.

Several chapters deal with the history of Irish nature study, noting that the first written accounts date from a St. Augustin (not the St. Augustine) in the 8th century, a work studied by the biologist/polymath D’Arcy Thompson.  The next such treatment was by a visitor named Giraldus in the 12th century; some of the information there may have come from natives.  The first report of Irish plants to go into print appears to be that of Richard Heaton, a British cleric posted to Ireland in 1630.  By this time the country was well under Britain’s thumb, so much of the work that follows was done by Anglo-Irish or British botanists.  Arthur Rowdon was a prominent landowner with one of the first greenhouses in Ireland.  He is important to botany because he was a friend of the botanical collector Hans Sloane through whom the British botanist William Sherard came to live at Rowdon’s estate, perhaps as a tutor for his sons.  Sherard studied Irish plants and eventually became professor of botany at Oxford.  He was a friend of another Irishman, Thomas Molyneux, who acquired a herbarium created by the 17th-century pharmacist Antoni Gaymans.  This collection was annotated by Sherard and is still extant (Heniger & Sosef, 1989).  These are the kinds interesting side paths that run through the book.

Another one involves Caleb Threlkeld, who wrote the first Irish flora in 1727.  There is evidence that he must have seen a copy of Heaton’s work, and some of his text is derivative, using material from John Ray’s treatment of Irish plants.  However, Threlkeld made a real contribution of his own by noting when and where he saw the plants he described.  Also, present-day Irish botanists have studied old specimens at the Trinity College, Dublin herbarium and make a case that these were collected by Threlkeld, thus substantiating his observations (Doogue & Parnell, 1992).  The Trinity herbarium was also home base for the algologist William Henry Harvey, who added substantially to its collection with specimens from South Africa and Australia, including his reference herbarium from his visit to the latter.

When I met the Trinity herbarium’s present keeper, John Parnell, he emphasized that Harvey did many of his own illustrations, even to the point of making the engravings, because he wanted to insure the accuracy of what went into print.  Harvey’s work is magnificent, but it is not among the few botanical illustrations reproduced in the book, which is generally short on images.  There is, however, a chapter on “The Art of Nature Illustration” by Martyn Anglesea that cites several noted Irish artists, and highlights two who worked at another Dublin herbarium, that of the National Botanic Gardens of Ireland.  I have seen some of the work of Lydia Shackelton and Alice Jacob at the garden and it is amazing, especially the watercolors they did of orchids for Frederick Moore—a herbarium curator and expert on the family.

Before leaving this book, I have to mention Robert Lloyd Praeger who wrote The Way I Went, what some consider the best book for the general reader on the natural history and topography of Ireland.  He is most noted for his leadership of the Clare Island Survey (1909-1915), which involved over 100 amateurs and professionals and resulted in a landmark publication that set the bar high for future such European studies (Jones & Steer, 2009).  The Royal Irish Academy added to its value by funding a new survey of the island to mark the hundredth anniversary of the first.


Doogue, D., & Parnell, J. (1992). Fragments of an eighteenth century herbarium, possibly that of Caleb Threlkeld, in Trinity College, Dublin (TCD). Glasra, 1(2), 99–109.

Foster, J. W. (Ed.). (1997). Nature in Ireland. Montreal, Canada: McGill-Queen’s University Press.

Heniger, J., & Sosef, M. S. M. (1989). Antoni Gaymans (ca 1630–1680) and his herbaria. Archives of Natural History, 16(2), 147–168.

Jones, R., & Steer, M. (2009). Darwin, Praeger and the Clare Island Surveys. Dublin: Royal Irish Academy.

Praeger, R. Ll. (1937). The Way That I Went. Dublin, Ireland: Hodges, Figgis.

Threlkeld, C. (1727). Synopsis stirpium Hibernicarum alphabeticæ dispositarum. Dublin, Ireland: Powell.

Books Old and New, Part 2: Botanical Monkeys and a Suitcase

2 Corner

Landmark Press, Singapore (2013)

The last post was the first in a series on books I’ve encountered—both recently and in the past—and found interesting.  This entry focuses on two books with intriguing titles.  The first is Botanical Monkeys, published by E.J.H. Corner in 1992.  The title is more literal than you might think.  It deals with this British botanist’s use of southern pig-tailed macaques or beroks, Macaca nemestrina, to collect specimens in Malaya (now part of Malaysia) in the 1930s.   In an earlier post, I dealt with the frustration of botanists whose specimens get destroyed by insects and mold in rainforest environments.  Another cause of frustration in such areas is the difficulty of obtaining specimens of hard-to-reach species, particularly epiphytes living high up in the tree canopy.  Today there are sophisticated rope and pulley systems that make the forest’s upper reaches more accessible, but when Corner was collecting there was no such technology.  He found small trees scalable, it was in obtaining flowers and fruits from mid-sized and very tall trees that he needed help.  He had to wait for foresters to fell large trees before he could obtain canopy plants.

As early as 1929, Corner had noted that a berok would climb a tall coconut tree and twist off the nuts.  When he suggested using the monkeys for collecting, his colleagues discouraged him by noting that even if the animals could be taught to grab specimens, these would probably get caught in the lower tree limbs when they threw the plants down.  But he remembered the idea.  Later he saw a berok pull flowering twigs from a mango tree and select a bunch of fruit from a rambutan tree, related to the lychee.  With its teeth it also tugged off a pigeon orchid from a branch and some mistletoe.  When they were dropped, none got caught on the way down.  While other monkeys also foraged in the trees, beroks seemed particularly good candidates to become collectors because they liked to hear material crashing down.

To put his plan into operation, Corner captured a few young beroks and taught them to twist off palm nuts.  He would keep a collector on a rope and slap the trunk of the next tree to get it to move on, at the same time loosening the cord.  He also gave verbal commands, and one monkey knew 24 Malay words.  Merlah, the first one he trained, collected specimens from more than 300 species of trees.  In appreciation, Corner named a species after him.  Another collector, Putch, was so well-trained that he was allowed to go off on his own.  Sometimes Putch would spend 15 minutes collecting, eating, and playing before reemerging.  Corner would take notes and then shout and hit the next tree.  Needless to say, there were sometimes problems.  For example, the animals were trained to rip off branches with leaves, but they would ignore the flowers; it took time to get them to collect both.

This botanical and zoological experiment ended, as does Corner’s book, with the Japanese invasion of Malaya.  However, this is where another oddly titled book gets interesting.  A few years ago I read a review of My Father in His Suitcase by John K. Corner (2013), who is E.J.H. Corner’s son.  It cost $100 at the time and I wasn’t that intrigued, but I kept checking its price on used book websites until it came down to about $30; then I was willing to satisfy my curiosity.  There is a great and difficult story behind this odd title.  Even though E.J.H. didn’t die until 1996, John Corner, who was called Kay, left home in 1960 at the age of 19 and never saw his father again.  E.J.H. was divorced from Kay’s mother and his second wife did not relate well to Kay, who also had a difficult relationship with his father.  Because of this deep estrangement, Kay was surprised when a cousin received a suitcase stuffed with papers shortly after E.J.H.’s death.  It was labeled: “To Kay, wherever he might be.”  That was the only message, and Kay was so bitter that it was years before he even opened the bag.  Despite urging from his wife and other family members, he couldn’t bring himself to do it until he had retired and they had moved to Australia.  In the case he discovered an odd combination of letters, school reports, scientific articles, and other memorabilia.  He became intrigued by what he found, carefully studying the material and contacting relatives as well as those who had known his father to learn more about this man whom he had mentally attempted to bury for so long.

Kay’s book is hardly a conventional biography.  It’s main sources came out of that suitcase and were the means through which he came to know his father better.  The son writes of his father’s years working in Malaya, including his stormy marriage to Kay’s mother, his botanical research, and his work in Japanese-occupied Malaya.  This last is a difficult subject because many consider the senior Corner a traitor for his collaboration with the Japanese who allowed him to maintain the botanical garden he headed.  Kay defends E.J.H.’s work saving important Malay plant collections and then describes some of his father’s later contributions to botany including his years as a professor of tropical biology at Cambridge University, but it is the personal side that dominates.  It’s a most affecting and unusual portrait of a botanist.  In the end, it doesn’t seem that John Corner has come to like his father, but his views are much richer and more ambivalent than they were when he first undid the suitcase’s clasps.


Corner, E. J. H. (1992). Botanical Monkeys. Edinburgh, UK: Pentland Press.

Corner, J. K. (2013). My Father in His Suitcase. Singapore: Landmark.

Books Old and New, Part 1: Notebooks and Sketchbooks

1 Notebook

Firefly Press, Buffalo, NY (2016)

I recently moved house after 30 years and decided it was a good time to cull my books.  Years ago I had read that Doris Grumbach, a writer, professor of literature, and professional book reviewer, tried to de-acquisition half her books every time she moved.  I attempted to follow suit, no small task.  I did pretty well, and one outcome of the exercise is that I was reminded of books I had read and loved in the past, but hadn’t considered in some time.  In this series of blogs I want to share a couple of them because I think they are worth passing on.  Also, I have to admit that since moving, I’ve bought a few more books.  After all, any collection—of herbarium specimens or books—grows stagnant if not “curated” and nourished.  So I’ll cover a couple of these, too.

One of the latter is Explorers’ Botanical Notebook (Thinard, 2016).  When I leafed through it in the library, I decided I had to own it.  It’s an obvious choice for this blog because it’s full of photos of herbarium specimens drawn from the collections of the Royal Botanic Garden, Kew in Britain and the University of Montpellier in France.  As the title implies, the book is about exploration and is organized as two-page spreads, with the description of an expedition on the left, and the photo of a related herbarium specimen on the right.  Many obvious voyages are included such as Joseph Banks and Daniel Solander on Captain James Cook’s first circumnavigation of the globe, the Lewis and Clark expedition, and Charles Darwin on the Beagle.

For each voyage there is a relevant specimen.  The problem is that the level of relevance varies, one reason being that the book includes very early travels dating back long before the development of herbaria—and I do mean very early.  The first is the expedition Queen Hatshepsut of Egypt mounted around 1465 BCE to search for sources of myrrh and frankincense for embalming.  This shows that plant hunting definitely has a long history, but the frankincense (Boswellia carterii) specimen pictured is from 1875.  In this case, as for the discussion of Alexander the Great’s plant finds during his conquests (334-325 BCE) and Marco Polo’s travels on the Silk Road, there is obviously no physical botanical evidence to display.  However, for other exploits there are, even relatively early ones such as the pirate William Dampier’s plants collected in Western Australia in 1699 and Joseph Pitton de Tournefort’s specimens from the Levant at about the same time.  I assume that they are not pictured because there were no relevant specimens in the two collections used as source material.  However, there is another disconnect that may or may not be related to availability of relevant sheets.  For example, there is a four-page spread on David Livingstone and John Kirk’s exploits on the Zambezi River, but the plants pictured aren’t mentioned in the text.  This is frustrating and makes the presence of the specimen much less compelling, even though they were collected by Kirk.

I know that I’ve been rather negative about this book, so why do I even bother to review it here?  Well, it does provide an opportunity to look at some beautiful and historically important specimens.  While the Kew and Montpellier collections have certain deficiencies, they also have remarkable strengths.  After all, Kew is one of the most comprehensive herbaria in the world and some of its treasures are displayed here, including specimens collected by  Charles Darwin and Joseph Dalton Hooker.  There are also wonderful stories such as that about the specimens of Jacques Julien La Billardière who traveled from France to the Pacific.  Neither he nor his plants had an easy time of it.  He was a French royalist and when word reached the ship in Java that Louis XVI had been guillotined, the republicans on board rebelled and handed La Billardière over to the Dutch who imprisoned him and confiscated his collections.  The Dutch ship carrying his specimens was captured by the British, and the Frenchman’s specimens ended up with the British botanist Joseph Banks.  In a noteworthy example of international solidarity among scientists, even when their countries were at war, Banks sent the crates back to France without even opening them.

I had read this story before, but it’s worth revisiting, and the same is true of many of the book’s entries.  If you are well-versed in the history of botany, there isn’t much to learn in these brief treatments, but for those with an amateur interest in plants, there’s a great deal of good material here.  Two other books I bought recently are related to this one.  Explorers’ Sketchbooks (Lewis-Jones & Herbert, 2017) gives examples from a variety of fields.  There are a number with botanical material included, some with which I wasn’t familiar such as Philip Georg von Reck’s (1711-1798) notebook.  He went with James Oglethorpe to Georgia in 1734 on the latter’s second trip to develop the Georgia colony.  Von Reck made some of the earliest records of plants and animals in the area.  I found many of the geologists’ sketches equally fascinating; it’s interesting to see how they dealt with great differences in scale from massive geological formations to the texture of individuals pieces of rock.  Botanical Sketchbooks (Bynum & Bynum, 2017) is also spectacular.  This is a book I hope to keep, not matter how much I may have to pare my library in the future.  Again, there is a mixture here of the usual suspects like Joseph Hooker and also Sydney Parkinson, Joseph Banks’ artist on Captain Cook’s first round the world voyage, in addition to the less well known such as Hellen and Margaret Shelley, sisters of the poet Percy Shelley, and Charles Maries who studied mangoes in India.


Bynum, H., & Bynum, W. (2017). Botanical Sketchbooks. New York, NY: Princeton Architectural Press.

Lewis-Jones, H., & Herbert, K. (2017). Explorers’ Sketchbooks. San Francisco, CA: Chronicle.

Thinard, F. (2016). Explorers’ Botanical Notebook. Buffalo, NY: Firefly.

Nature Prints as Art

4 Eden

Announcement for Propagating Eden exhibit at Wave Hill, Bronx NY

I firmly believe that art and science can’t be separated, and that this is particularly true in botany.  Plants are simply beautiful, and that beauty has attracted many people to study them more closely, even in this age of “plant blindness.”  For some, nature printing has become an absorbing hobby, with the Nature Printing Society having several hundred members.  It publishes a newsletter that focuses on techniques as well as reviews of published works with nature prints.  The Society has also produced an informative guide to nature printing, not only of plants but of animals as well, particularly fish (Huffman, 2016).  For the latter, the primary technique is Japanese gyotaku that creates stunning works that even a botanist could love.

Since I’m interested in the fabric arts, particularly quilting and embroidery, I’ve gotten a couple of books on nature printing on fabric as well as paper (Bethmann, 2011; Dahl, 2002).  I’ve used the technique just enough to know that, like creating herbarium specimens, there is quite a bit of expertise involved that only practice will make anywhere near perfect.  However, the basic idea is simple; it’s something that a child can do with a sturdy leaf covered with marker ink on one side and pressed on a sheet of paper.  There is a magic to this because it’s a way to make venation a focus of attention.  I keep coming back to the Mabey (2015) quote with which I began this series of posts to the effect that no technique can capture the essence of a plant perfectly.  However, nature printing can very effectively highlight certain aspects of that essence.

Several years ago, there was an exhibit at the Wave Hill estate in the Bronx, NY on nature printing in botany and art.  It was there that I fell in love with the technique because this rather small exhibit captured the history of nature printing so thoroughly.  It included some of the earlier works that I’ve already cited such as those of Franklin, Atkins, Auer, and Bradbury.  But what really grabbed my attention were the various ways in which 20th and 21st-century artists have employed nature printing.  Kiki Smith was represented by a lithograph with pressed leaves.  Another striking example was Ed Ruscha’s Clock of 1994 with what appears to be dried grass glued to the page, but is actually a print made by a proprietary technique called Mixografia, a relief color printing process.

In conjunction with this exhibit, there was a symposium on several aspects of nature printing:  Karen Reeds (2006) spoke on the technique’s history, including her research on Leonardo Da Vinci’s role, Patricia Jonas compared nature prints with herbarium specimens, and Michele Oka Doner described using nature prints in her art.  In the show was a striking Doner print of what looked like the tree of blood vessels in the lungs, but was in reality a print made with roots of banyan trees that she collected from the beach near her Florida home.  This work a beautiful example of how branching patterns are ubiquitous in nature, as are her massive prints of the human body.  As an aside, I have to add that several months later I encountered her work again, this time at the Frederik Meijer Gardens and Sculpture Park in Grand Rapids, MI.  Doner designed the floor of the visitor’s center—an installation called Beneath the Leafy Crown (2009)—with 1600 “prints” of plants and invertebrates done in bronze and embedded into terrazzo (Becherer, 2010).

In his extensive historical review of nature printing, Roderick Cave (2010) cites other nature printers who were artists rather than botanists.  Most notable is the surrealist Max Ernst who used what he called frottage:  making rubbings from the surface of wood or other materials, especially in his series Histoire naturelle of 1926.  Arthur Rushmore, an American print maker, developed his own technique for creating what he called “hay prints,” which influenced later artists.  The British artist Morris Cox also employed prints imaginatively, combining them with his poems.  Some are quite fanciful, such as a human figure of printed grass, others are more reminiscent of 19th-century colored prints of flowers.  He sometimes also included a favorite subject of earlier printers: lace.

I want to end with the work of one of my favorite contemporary nature printers, one who unfortunately passed away shortly after publishing an amazing book that I mentioned in an earlier post on xylaria and tree rings.  It’s Woodcut by Bryan Nash Gill (2012), a collection of, quite literally, wood prints.  Gill would cut a slice through a tree trunk, meticulously sand it, apply ink, and make relief prints of the wood’s raised grain.  He printed not only cross sections of trunks, but cuts through milled planks as well, often juxta-positioning them in interesting patterns.  His works are definitely in the realm of art not science, but for the botanist they are still wonderful reminders of the beauty and mystery beneath the surface of a tree, beneath the bark.  This reminds me, that bark, too, can be a subject for the nature printer, and this will be my next art project.  I doubt that it will result in a great work of either art or science, but I am sure I will learn something more about the printing process and about the wonders of bark texture.


Becherer, J. (2010). Michele Oka Doner. Grand Rapids, MI: Frederik Meijer Gardens and Sculpture Park.

Bethmann, L. D. (2011). Hand Printing from Nature. North Adams, MA: Storey.

Cave, R. (2010). Impressions of Nature: A History of Nature Printing. London: British Library.

Dahl, C. A. (2002). Natural Impressions. New York, NY: Watson-Guptill.

Gill, B. N. (2012). Woodcut. New York, NY: Princeton Architectural Press.

Huffman, S. (2016). The Art of Printing from Nature: A Guidebook from the Nature Printing Society. Lake Shore, MN: Nature Printing Society.

Mabey, R. (2015). The Cabaret of Plants: Forty Thousand Years of Plant Life and the Human Imagination. New York, NY: Norton.

Reeds, K. (2006). Leonardo da Vinci and botanical illustration: Nature prints, drawings, and woodcuts ca. 1500. In Visualizing medieval medicine and natural history, 1200-1550 (pp. 205–237). Burlington, VT: Ashgate.

Nature Printing in the 19th Century

3 Bradbury Fern Plate 1

Plate 1 from The Ferns of Great Britain and Ireland.

Another name for nature printing is self printing because it is the inked plant itself that makes the print, rather than an artist creating marks on paper, independent of the specimen.  However, ink isn’t necessary, sometimes light itself can work, as when a plant is set down on photosensitive paper and then exposed to light.  That was how Anna Atkins produced cyanotypes of algae such as the one above (Armstrong & de Zegher, 2004).  Her first book of these is argued to be the earliest publication of any form of photography (1843-1853).  Atkins produced 400 plates in 11 years, but the process she used required a unique exposure for each copy, so it’s no surprise that there are less than a dozen copies of this work (Bridson & Wendel, 1986).  Such a project was obviously labor intensive, and over the years several printers attempted to devise ways of increasing the number of prints from one plant.  As mentioned in the first post in this series, Benjamin Franklin managed to make impressions in soft lead, but the technique was still time-consuming and messy.  Roderick Cave (2010) describes this and many other attempts in his book on nature printing.

In terms of output, the most successful nature printing technique was that developed by Alois Auer, who became director of the Austrian National Printing Office in 1841.  He experimented with gutta-percha (a gum with some properties similar to soft plastic) to make prints of fish and then create an electrotyped copy from it.  Electrotyping means employing an electric current to lay down a thin layer of copper on the print.  The copper is set on a harder metal background and used for the actual printing; it is much more durable than the original print.  However, the gutta-percha prints often looked messy.  The next approach was to pass specimens through a rolling press between plates of polished lead and steel.  This made a cleaner impression in the lead, which could then be used to create an electrotype copy.  Several large-scale botanical projects employed the method, often using colored inks.  Some of the most successful were of algae.  As I have described in an earlier post, collecting and studying seaweeds were popular pastimes in the mid-19th century, particularly among women.  Anna Atkins’s work is one indication of this.  When properly prepared, either as specimens or nature prints, seaweeds were beautifully delicate.  Since they were plants without flowers, which often didn’t print well, the prints were satisfying even when produced in a single color.  However the Auer method was also used on higher plants.  The Imperial Printing Office’s largest project produced five folio volumes of nature prints of Austrian plants (Ettingshausen & Pokorny, 1856-1873).

Auer, who had a patent on his process, was not without competition.  Carlo and Agostino Perini  created a Flora of Italy, over a span of 11 years (1854-1865) using Auer’s method, but production costs were high.  Henry Bradbury, the son of an established British printer, asked Auer if he could visit Vienna and learn about the process.  Auer agreed and was apparently quite forthcoming in showing Bradbury how the printing was done.  Upon his return to England, Bradbury took out a patent on what he claimed was a different and better technique, but Auer argued that the process was essentially the same as that used in Vienna.

A great deal of acrimony developed between Auer and Bradbury, but in the meantime, Bradbury published a few of the most impressive works in the history of nature printing.  First there was A Few Leaves Represented by Nature Printing, a brief, relatively inexpensive folio to show off the method.  The Bradbury printing style accentuated the venation of the leaves, making them seem almost transparent, an attribute that many botanists saw as misleading.  The most spectacular Bradbury publication was the large folio format The Ferns of Great Britain and Ireland (see figure above).  I have seen a copy of Ferns in the library of the Delaware State University herbarium, and it is indeed a wonder to behold.  Like ferns seaweeds seem to lend themselves to the technique, and Bradbury created a multi-volume work on algae that is spectacular in its display of beautiful forms and colors, but wasn’t as popular as the fern book.  The seaweed publication marked the end of this particular chapter in nature printing since Bradbury committed suicide in 1860.

At least a few 19th-century botanists found nature printing a useful way to document plants in the field (see last post), and there were also a few who used prints in their publications.  Not surprisingly the latter were mostly Austrians who published through Auer’s Austrian National Printing Office.  Constantin von Ettinghausen was interested in paleobotany and employed the technique in his publications for over 40 years.  He found nature printing skeletal leaves a good way to compare living plants with fossils and used the technique in his publications for over 40 years.

Despite Austrian expertise in the field, the most massive nature printing project was produced in France.  Herbier de la Flore Française (Cusin & Ansberque, 1867-1876) ran to 26 volumes with over 5,000 plants, however the printing technique used for these books created what Cave calls “rather dull” plates (2010, p. 147).  He cites many other interesting types of nature prints, including their use in decoration during the height of another 19th-century plant-related fad:  fern mania.  This brings to the fore the aesthetic appeal of nature printing that becomes the dominant focus in 20th and 21st-century printing projects, which will be the subject focus of my final post in this series.


Armstrong, C., & de Zegher, C. (2004). Ocean Flowers: Impressions from Nature. Princeton, NJ: Princeton University Press.

Atkins, A. (1843). Photographs of British Algae: Cyanotype Impressions (5 volumes).

Bridson, G. D. R., & Wendel, D. E. (1986). Printmaking in the Service of Botany. Pittsburgh, PA: Hunt Institute for Botanical Documentation.

Cave, R. (2010). Impressions of Nature: A History of Nature Printing. London: British Library.

Cusin, M. L., & Ansberque, E. (1868). Herbier de la flore française. Lyon: s.n.

Ettingshausen, C., & Pokorny, A. (1856). Physiotypia plantarum austriacarum: Vienna, Austria: Imperial Printing Office.

Perini, C., & Perini, A. (1854). Flora dell’Italia. Trento, Italy: Tipografia Perini.

Nature Prints as Botanical Documents

Nature print of Cassia by Thomas Horsfield at the

Nature print of Cassia by Thomas Horsfield at the Academy of Natural Sciences of the Drexel University, Archives and Manuscript Collection #625

Alexander von Humboldt and Aimé Bonpland are justly famous for their five-year exploration (1799-1804) of parts of South and Central America as well as the Caribbean.  They brought back thousands of plant specimens as well as rocks, fossils, and the remains of animals.  Also in the haul sent to Paris were over 200 nature prints that weren’t given much attention before the 21st century.  Even the two explorers said little about them in their journals and letters, though they did annotate them.  For several years after their return, Bonpland worked on the plant collection in conjunction with Humboldt and the German botanist Carl Kunth at the Natural History Museum in Paris.  In 1816 Bonpland decided to return to South America, taking the plant specimens with him; they were only returned to Paris 1858.  However, Kunth managed to catch up with Bonpland in La Havre before he sailed and retrieved six volumes of field notes and the nature prints.  Kunth used these reference materials in identifying some of the species Humboldt and Bonpland had discovered.  Before Kunth returned to Germany in 1829, he donated the prints to Benjamin Delessert, a wealthy amateur botanist, whose heir in turn gave them to the Institut de France where they remain.  They were highlighted in an exhibit about Delessert in 1993, and this was how the Austrian botanical historian H. Walter Lack came to know of them and write an article on them (2001).

It seems that Humboldt and Bonpland were driven to make nature prints because they lost so many herbarium specimens.  Lack quotes from a letter Humboldt wrote to the botanist Carl Willdenow in Berlin:

“Alas, almost in tears we open our plant boxes.  Our herbaria have the same fate lamented already by Sparman, Banks, Swartz and Jacquin.  The immense wetness of the America climate, the rankness of the vegetation, which makes it difficult to find fully grown leaves, have destroyed one third of our collection.  Every day we find new insects which destroy paper and plants.  Camphor, turpentine, tar, pitched boards, hanging boxes fixed on ropes in the open, all tricks devised in Europe fail here, and our patience has become tired.  After being absent for 3-4 months you hardly recognize your herbarium, you have to discard 5 out of 8 specimens (p. 220).”

Since the paper Humboldt and Bonpland used for printing had Spanish watermarks, they likely didn’t originally plan to make prints and didn’t take printing supplies with them, but bought some in the Spanish colonies they visited.  Though they were probably both involved in printing, Bonpland, whose specialty was botany, likely took the lead.  Most of the annotations are his, with a number in Humboldt’s handwriting.  The pair were among the first collectors to number their specimens and numbered the prints in the same series with the plants themselves.  The numbers indicate that prints were made over a long period of time—perhaps after a spate of specimens were lost their frustration level would again mount and lead to more printing.  Many of the prints are annotated by Kunth; he gave them determinations that were then published in the Nova genera et species plantarum.

As Lack notes at the end of his article, the use of prints by botanists remained an “isolated phenomenon,” but it wasn’t a unique one.  The American naturalist Thomas Horsfield made prints during the almost 20 years (1801-1819) he spent in Java as a surgeon working for the East India Company (EIO).  Collecting was his passion and his botanical prints were one manifestation of this.  I have written about them in a previous post, but they should be mentioned here for two reasons.  First, they are of amazingly good quality.  Roderick Cave (2010), an expert on nature prints, considers them among the best he has ever seen, which is high praise indeed.  One reason for the quality is that Horsfield used softer Chinese paper rather than firmer European paper.  Horsfield, or perhaps an assistant, inked both sides of each specimen, folded a large sheet around it, and burnished it from the back, making mirror-image prints.  One bound set of prints are at Drexel University’s Academy of Natural Sciences Library, and I’ve been fortunate enough to examine them.  Their delicacy and detail are exquisite, and the quality is consistent throughout the collection.  The book is accompanied by an index of the plants, most with at least a genus name given and in some cases the Javanese name as well; the arrangement is Linnaean.  This is one of three known copies; the other two are in England (Peck, 2014).

The other reason for mentioning Horsfield is that like Humboldt and Bonpland, he was driven to nature printing because of the difficulties in preserving specimens, though, like them, he sent thousands of specimens back to London, to his employer’s headquarters.  He eventually went to England and spent the rest of his life in the employ of the EIO working on its collections and writing up his results (Horsfield, 1990).  Along with John Bennett and Robert Brown, he published Plantae javanicae rariores (1838-1852) documenting his botanical discoveries.  The illustrations are in part based on the prints as well as on his specimens.  Here as with Humboldt and Bonpland, nature prints made a significant contribution to important works on exotic flora.  While this is only a drop in the ocean of botanical publications, it deserves attention.  In the next post, I’ll examine how botanical nature printing developed later on in the 19th century when it had its greatest influence.


Bennett, J. J., Brown, R., & Horsfield, T. (1838). Plantae Javanicae rariores. London: Allen.

Cave, R. (2010). Impressions of Nature: A History of Nature Printing. London: British Library.

Horsfield, T. (1990). Zoological Researches in Java, and the Neighboring Islands. Singapore: Oxford University Press.

Lack, H. W. (2001). The plant self impressions prepared by Humboldt and Bonpland in tropical America. Curtis’s Botanical Magazine, 18, 218–229.

Peck, R. M. (2014). Discovered in Philadelphia: a third set of Thomas Horsfield’s nature prints of plants from Java. Archives of Natural History, 41(1), 168–170.

Botanical Nature Prints: An Introduction

Print of Campanula by Zenobe Pacini in the Bibliotheque Nationale de France

Nature print of Campanula by Zenobe Pacini in the Bibliothèque nationale de France

Creating a herbarium specimen is an attempt to pin a plant down, to capture it on a page.  Obviously, this aim is only semi-successful.  The plant is physically present, but the life has gone out of, as has much its dimensionality and color.  Still, it contains a great deal of taxonomic information, and often DNA and other diagnostic chemicals.  Visiting a plant in the field may be impractical as is propagating every plant under study; photographs can document form and dimensionality, but they have no DNA, nor do botanical illustrations, which are time-consuming to produce.  In other words, there’s no perfect way to capture a plant.  As Richard Mabey (2015) writes:  The quintessence of a plant can only ever be a fantastic goal, something to travel towards but never reach (p. 27). But there is another answer, though again it isn’t a perfect solution.  That is the nature print, the subject of this set of posts.

Usually, a nature print of a plant involves inking one or both sides of a flattened specimen, sandwiching it between pieces of paper and applying enough pressure, either by hand or instrument, to transfer ink from plant to paper.  The process definitely has severe limitations, which is why it’s not part of most botanists’ repertoire.  Details of flower structure usually don’t show up well nor do any thick or fleshy plant parts.  Still, it can produce fascinating results, such as the prints I saw in an anonymous collection of prints at Oak Spring Garden Library (Tomasi & Willis, 2009).  It was created in Britain in the early 1700s by some avid plant collector, probably an amateur, yet one who could identify the common names for each of the specimens in a carefully created index at the beginning of the book.  While here the emphasis was on leaves, other printers included, or tried to include, stems and flowers, which often didn’t print as well.  The Oak Spring Garden Library also has a published nature print book by Christian Gottlieb Ludwig from 1760.  It has beautiful prints that have been colored, but the flowers are mostly painted in with rather stylized forms (Tomasi and Willis, 2009).  If nature printing results were often imperfect, why did the technique come into rather frequent use in the 16th century, reach an apex in the 19th, and still be popular at least among artists and amateurs into the 21st?

Answers to this question can be found in the best book I’ve seen on the subject, Roderick Cave’s (2010) Impressions of Nature: A History of Nature Printing.  He cites a print from as early as 1320 and also discusses Leonardo Da Vinci’s description of the technique, which was accompanied by a print of a single sage leaf.  As botany developed into a science in the 16th century, some of those who documented plants with illustrations and herbaria also created nature prints.  These include Conrad Gessner, Thomas Kentmann, Felix Platter, and Fabio Colonna.  There is evidence that at least the latter used prints as references in creating the illustrations for his book.  Among the most magnificent prints from this time are found in the 1520 volume created by the pharmacist and perfumer Zenobe Pacini, who enhanced the prints by coloring them and adding details in watercolor.  In the 17th century, the work of Paolo Bocconne is also remarkable; his prints are now available online and well worth examining.

It’s likely that it was Bocconne who brought the technique to England and perhaps taught it to the avid botanist, William Sherard, whom Cave suggests passed it on to his colleagues.  In the 18th century, the Spanish explorer Joanne Garcia de Chaves y Guevara, made nature prints of the plants he found in California (Cave, 2010).  And on the east coast of North America, Benjamin Franklin, who may have learned the technique in Britain, worked with Joseph Breintnall to use leaves in creating currency.  Since it would be difficult to copy the venation of a leaf precisely, they devised a way to transfer the leaf impression to type metal for printing money.  Breintnall also sold leave impressions as references for amateur botanists; he leaves he at John Bartram’s farm on the outskirts of Philadelphia.  Farther north, Jane Colden, a botany enthusiast as was her father Cadwallader Colden, created over 300 nature prints of native plants she found growing near their farm in New York State.

The Coldens were serious about the study of native plants and printing was Jane Colden’s means of documenting at least something of what these plants looked like.  It was more efficient than trying to draw them all, though she did do illustrations as well.  Nature printing was a way to hold on to something of a plant after an encounter with it.  The British notebook at Oak Spring Library that I mentioned earlier is one example of this, as is another from Germany, also anonymous but created later, in 1824 (Tomasi & Willis, 2009).  Bound into the manuscript is a pamphlet published in 1797 by Johann Friedrich Korn that presents prints of tree leaves and also describes how to make prints (Raphael, 1989).  This suggests the process was popular enough that publishers sought to profit from the interest.

While some amateur and professional botanists created herbaria, others chose to make prints or to use a combination of techniques.  For over 50 years, John Jacobs Thomas kept a notebook, now at New York Botanical Garden, recording 367 apple varieties as well as a number of other fruits (Fraser & Sellers, 2014).  For some of these, he included prints of cross sections.  In one of his field note books, the USDA botanist David Griffiths, who was exploring in the Southwest US, made prints of prickly pear fruits to document their differences.  In both cases, the prints served the serious purpose of recording what measurement along could not, and doing this for fruits that would have been difficult to preserve on a herbarium sheet.  In the next post, I will discuss botanists who were led to create nature print collections for other reasons while exploring remote parts of the world.


Cave, R. (2010). Impressions of Nature: A History of Nature Printing. London: British Library.

Fraser, S. M., & Sellers, V. B. (Eds.). (2014). Flora Illustrata: Great Works from the LuEsther T. Mertz Library of the New York Botanical Garden. New Haven, CT: Yale University Press.

Korn, J. F. (1797). Sammlung von 50 in Kupfer. Breslau: Hirschberg und Liss.

Ludwig, C. G. (1760). Ectypa vegetabilium usibus medicis. Halae Magdeburgicae.

Mabey, R. (2015). The Cabaret of Plants: Forty Thousand Years of Plant Life and the Human Imagination. New York, NY: Norton.

Raphael, S. (1989). An Oak Spring Sylva: A Selection of the Rare Books on Trees in the Oak Spring Garden Library. Upperville, VA: Oak Spring Garden Library.

Tomasi, L. T., & Willis, T. (2009). An Oak Spring Herbaria: Herbs and Herbals from the Fourteenth to the Nineteenth Centuries. Uppervil