Tuesday, January 21, 2014

Spontaneous trefoil?

On the lower left of HS 242 f. 110, one of Lawson's collections, is a label covering what appears to be a plant specimen. It's quite small, and the bit that appears most clearly looks like a trifoliate something-or-other. A Desmodium, perhaps? Who knows. Weakley includes the common name "trefoil" in eight different plant entries - anything with leaves clumped in threes can merit it.

The intriguing thing is the label, which is evocative. (At least, my attempt at deciphering it is evocative.) It appears to read:

"Jan. 27th 1710. Spontaneous [?] trefoil of Carolina growing on the fork of Neus River and in other places having shed [?] from flower like drops of blood a sweet herbage[??] all spontaneous trefoils are more hairy here than in England."


I may have gotten that completely wrong.

But what if I'm right, and it does refer to "spontaneous trefoil"? Did people believe plants could grow spontaneously? Is trefoil a particular weed, common in England?

I found this account in The Farmer's Magazine, London 1851 (MDCCCLI - I hate Roman numerals!) describing a case of trefoil growing in fields sown with clover. Because the seed produced pure clover in most fields, the farmers concluded that the trefoil must have grown spontaneously. The author refuses to believe this, noting that seeds could lie dormant for years until conditions were right for them to germinate, but it is intriguing, no?

Then there's this, from the Annals of Agriculture, and Other Useful Arts, published London 1804: "Gypsum has also another very singular property, that of encouraging the growth of spontaneous trefoil on spots where seed had never been sown, particularly of the yellow and white trefoil. In Alsace I have seen many instances of this singular circumstance."

And this, on the adulteration of forage plants, another author recognizing that yellow trefoil seeds can last a long time.

What is trefoil? I'm not going to attempt to identify this specimen, but I can speculate more on my musings. This UK lawn weed site identifies Trifolium dubium as the noxious weed Lesser Trefoil - it's a Eurasian native, and is introduced to our area, so maybe not that. Plant Guide.org identifies it as Medicago lupulina, also introduced to our area. Weakley includes the common name "trefoil" in eight different plant entries - anything with leaves clumped in threes can merit it.

Sadly, our photographs do not allow us to see through that unfortunate label to further examine the plant specimen. So the mystery will have to stop here for now.

Friday, January 17, 2014

Taxonomic hierarchies

How do we sort things? Let me count the ways....

Modern scientific taxonomy got started with Carl Linnaeus (1707-1778). He was the man, I must say. After spending his younger years exploring the botanical biodiversity of Sweden and northern Europe, he dedicated his mature years to sitting in Uppsala and organizing the pieces of the world that came to him in the mail. Explorers went out to sea at his behest, and some of them - the ones that survived - sent him specimens of plants, animals, stones, whatever.

Linnaeus decided to organize everything. At the time the world must have seemed suddenly knowable, all things coming clear. Everything must belong to a type, and all types must fit into a hierarchical structure. (Could it be Latin grammar that gave him this idea?)

Linnaean organization especially emphasizes two things: kingdom and genus. Kingdom defines the nature of the beast. Genus names a category and allows specification to produce a binomial - a scientific name.

To start with the binomial: The scientific name of a species consists of two names, genus and species. The genus is its generic name, or category. The species is the name of a specific type of organism within that category.

Take the lion, Panthera leo. The generic category is panthers. What kind of panther? The "lion" kind. You could also have the "tiger" kind of panther, Panthera tigris, or the leopard kind of panther, Panthera pardus, which actually means "Panther panther." (The word "leopard" comes from two Greek words meaning "lion panther," so our common name for leopard means the same thing as the scientific name for lion. Haha!)

All those generic panthers belong to the cat family Felidae. So do generic little cats, in the genus Felis, "cat" in Latin. Linnaeus named our domestic cat Felis catus. Catus is another Latin word for cat. So a domestic cat is the "cat" kind of cat. Another little cat is called Felis silvestris, the kind of little cat that lives in the forest. Simple!

Now kingdoms. Linnaeus created three kingdoms - Plants, Animals, and Minerals - to encompass everything in the world. Anything missing? Minerals fell by the wayside pretty quickly, but they weren't the real problem.

The invention of the microscope suggested that microorganisms didn't fit into either Plants or Animals. In the 1860s biologists added a new kingdom, Monera, for all single-celled organisms. But all single-celled organisms aren't alike. Some are small and primitive with no nucleus, and others are large and well-organized with nuclei and membrane-bound organelles. Scientists started calling them prokaryotes and eukaryotes. In 1938 they added another kingdom, Protista, to hold single-celled eukaryotes. The prokaryotes - bacteria and cyanobacteria - stayed in Monera.

Now, fungi are really not at all similar to plants - no chlorophyll, chitin cell walls - so in the 1960s they got taken out of Plantae and put in their own kingdom Fungi. And animals, plants, and fungi are all eukaryotes, so it was kind of important to put them with single-celled eukaryotes if cell structure was going to be a category. But they were ALREADY kingdoms. We needed another level of taxonomy. So that led to the short-lived empires - Prokaryota and Eukaryota. Kingdom Monera went into Prokaryota. Eukaryota got everyone else - Animalia, Plantae, Protista, and Fungi.

But in the 1970s and 1980s, biologists started focusing on common ancestry instead of physical similarity. Microbiologists announced that prokaryotes were not all bacteria, and that some were in fact very very different - so different they deserved their own kingdom. In the 1990s they got rid of Monera and replaced it with Bacteria and Archaea. The empires were changed into domains called Prokarya and Eukarya.

And that didn't even last very long. Now there are three domains. Eukarya still contains animals, plants, fungi, and protists. But the kingdoms Bacteria and Archaea are now in domains called Bacteria and Archaea. This leaves room for more discoveries.

Do we still need kingdoms? Does the genus-species naming structure still work? Clearly many things don't fit into the Linnaean schema. Plant taxonomy is full of subspecies and subfamilies and things just called clades or tribes. Hominin (human ancestor) taxonomy got stuck with a family called Homidae - all the great apes - and several named genera, but then has had to fit lots of categories in between them for extinct taxa. (Chimpanzees are currently grouped in a tribe called ... Panini. That's funny.)

And don't even get me started on the slime molds and water molds! Poor Phytophthora, dumped by Fungi. My kingdom for a kingdom! At least they still fit in Eukarya.

One obvious problem with imposing an organizing structure on the world is that one then forces the world to conform to the structure, rather than the other way around. (It's not an animal, and it's not a mineral, so it MUST be a plant....) On the other hand, we have to be able to talk about stuff. It will be amusing to watch this process unfold over the next decades. Will Linnaeus disappear entirely?

Monday, January 13, 2014

Catesby's bison, Darwin's Scotch Firs, and Roan Mountain

Every fall Patrick McMillan takes his Plant Taxonomy class on a field trip to Roan Mountain, TN, to study island biogeography and the ecology of high grassy balds. He talks about the importance of ecosystem engineers in keeping things stable - in this case, keeping the grassy balds grassy.

Grass won't just stay grassy on its own. Left to its own devices, it often will go back to forest, probably through an ugly transitional stage involving lots of brambly bushes. What keeps the bushes and trees from growing? Large animals. In the case of our grassy balds, it was the bison and Indians that used to roam the Appalachians. (Before that - maybe mammoths? But that's a very long time ago.)

There were bison up in the South Carolina mountains in Catesby's time. He writes about them:

Preface, viii.
"I then went to the upper uninhabited parts of the country, and continued at and about Fort Moore, a small fortress on the banks of the River Savanna, which runs from thence a course of 300 miles down to the sea, and is about the same distance from its source, in the mountains. I was much delighted to see nature differ in these upper parts, and to find here abundance of things not to be seen in the lower parts of the country; this encouraged me to take several journeys with the Indians higher up the rivers, toward the mountains, which afforded not only a succession of new vegetable appearances, but most delightful prospects imaginable, besides the diversion of hunting buffelo's, bears, panthers, and other wild beasts."

In his entry on the Pseudo Acacia, he also mentions the bufello:

Vol. 1, Appendix p. 20, Bison americanus and Pseudo Acacia hispida floridus roseis
"I never saw any of these trees but at one place near the Appalachian mountains, where Bufellos had left their dung; and some of the trees had their branches pulled down, from which I conjecture they had been browsing on the leaves.... I visited them again at the proper time to get some seeds, but the ravaging Indians had burn'd the woods many miles around, and totally destroyed them, to my great disappointment; so that all I was able to procure of this specious tree was some Specimens of is which remain in the Hortus siccus of Sir. H. Sloane, and that of Professor Dillenius at Oxford."

As it happens, there are no Pseudo acacia in the Sloane specimens today, but there are two (00087396X and 00087400J) in the Oxford collections. Patrick has identified them as Robinia hartwigii Koehne, Granite dome locust.

There are no bison roaming the grassy balds today (no Indians burning the locust trees either), though Patrick would love to see them restored. Instead, there are cattle grazing in some areas. The grazed parts are empty and grassy. Just beside those grazed bits are areas with the same basic ecological components but no cattle. Those parts are overgrown with brambles, bushes, trees - no grassy balds there.

Charles Darwin described this phenomenon in On the Origin of Species, in Chapter 4, "Struggle for Existence:"

"How important an element enclosure is, I plainly saw near Farnham, in Surrey. Here there are extensive heaths, with a few clumps of old Scotch firs on the hill-tops; within the last ten years large spaces have been enclosed, and self-sown firs are now springing up in multitudes, so close together that all cannot live. When I ascertained that these young trees had not been planted, I was so surprised at their numbers that I examined hundreds of acres of the unenclosed heath, and literally I could not see a single Scotch fir, except the old planted stumps. But on looking closely between the stems of the heath, I found a multitude of seedlings which had been perpetually browsed down by the cattle. In one square yard I counted thirty-two little trees; and one of them, with twenty-six rings of growth, had during many years, tried to raise its head above the stems of the heath, and had failed. No wonder that, as soon as the land was enclosed, it became thickly clothed with vigorously growing young firs."

"Here we see that cattle absolutely determine the existence of the Scotch fir...."

Monday, July 8, 2013

Rattle snakes and Alexipharmacal plants

Our intrepid Carolina explorers were always worried about rattlesnakes. What does one do about snakes that make frightening noises and whose bites can result in pain, bleeding, nausea and vomiting, low blood pressure, blurred vision, tissue damage, etc. (Although apparently not all rattlesnake bites even deliver venom; it's possible to get bitten and come to no serious harm.) The main effective treatment these days is antivenom, which wasn't around in the early 1700s. Catesby worried quite a bit about rattlesnakes - see his descriptions of their bites in the Natural History (vol. 2, p. 41), and in his plant collections.

Joseph Lord, living in coastal South Carolina in 1704, was also concerned. Three of his specimens contain labels mentioning the use of plants against rattlesnake bites. My favorite is this one, Eupatorium rotundifolium on H.S. 268 f. 35. His label reads:

“This (I think) I have sent you formerly without a name, as now it comes: but I desire you would please to let me know it’s name. Besides that an Indian told me of it's use in feavers, its found to be Alexipharmacal, & an admirable antidote against the Poison of Rattle-snakes in particular, conquering the Venom of their biteing. Gathered, Aug. 15, 1704, having been near a month in flower. It grows common in our woods, both in high & low land. There are divers other plants growing commonly that seem to be varieties of this.”

Alexipharmacal? I had to look that one up. It means an antidote, from the Greek words “ἀλέξειν, alexia,” meaning “to ward off,” and “φαρμακός, pharmakos” for “drug.”

Lord’s label makes it appear that the Indians and the Colonials who arrived here after them were all looking for the same thing as modern doctors - an antivenom. So would this plant work? Well, the closely related Eupatorium perfoliatum goes by the common name “boneset” or sometimes “ague-weed.” It was historically used to treat fevers and other assorted ailments. So maybe this one would work too.

One of the other rattlesnake plants is a specimen of Ageratina aromatica on H.S. 268 f. 33. Common name? “Small-leaved white snakeroot” or “Lesser snakeroot.”

Ageratina used to belong to the genus Eupatorium - of massive snakebite treatment fame. And Lord describes this one as “of the Tribe … of whose vertue against the biting of the rattle-snake I have made mention.” Sounds like taxonomy to me - long before Linnaeus.

Monday, June 24, 2013

Joseph Lord, a new 18th-century buddy

When I was in London a couple of weeks ago, I spent a day at the Natural History Museum, photographing a few more collections from the Sloane Herbarium. I had found three collectors we'd missed with our first round of photography. They are Joseph Lord, Col. Halsteed, and George Franklin - three guys who were in South Carolina between 1700 and 1710. That makes them the earliest collections we've worked with so far.

Joseph Lord is by far the most important of these three. Lord was a true American, born in Massachusetts in 1672 and educated at Harvard, after which he became a minister. (Did anyone from Massachusetts become anything else?) In 1695, Lord took a group of parishioners to South Carolina and founded the town of Dorchester. He built a house there and developed a plantation, which he mentions repeatedly in the notes to his plant collection.

Ah, yes, the plant collection! And the notes! Lord made his plant collection in 1704, and sent it to London to James Petiver, an apothecary who assembled a number of the collections in the Sloane. Lord's handwriting is beautifully legible, and he recorded useful details - things like color of flowers (a detail that is lacking in many herbarium specimens, which tend to be shades of brown), growing conditions, type of soil, and collection date. Patrick has already made good use of Lord's notes in the determinations we've begun.

We've already found something super cool - a specimen of Schwalbea americana, American Chaffseed, in the lower right corner of H.S. 158 f. 245.This is almost certainly the first collection of this plant, which is now in danger of dying out completely. This plant was listed as a federally endangered species in 1995.

American chaffseed is native to the longleaf pine ecosystem. It's a hemiparasite, or partial parasite - it performs some photosynthesis on its own but gets some of its nutrients and water by attaching itself to host plants with specialized roots called haustoria. It's not particular about hosts - American chaffseed parasitizes longleaf pines, hollies, and various grasses and composites. It's a fire-adapted species that depends on periodic fires to clear out vegetation to allow seeds to germinate and seedlings to establish themselves. Fires were regular occurrences in the longleaf pine savanna that was common in South Carolina before European settlement, but that has nearly disappeared from the region today.

This is one of the rarest plants on earth today. The 2008 5-year review noted 33 occurrences in South Carolina, 12 of which were considered protected but none with formal protection agreements and only one with a formal management plan. Almost all occurrences were in the Francis Marion National Forest. Total numbers had dropped between 1995 and 2008; and remember, those 2008 numbers are based on surveys done prior to 2008. So we don't really know how many of these plants are left. Some of these areas are being managed with controlled burns, which benefits a whole range of fire-adapted species. But there's not much space for them, and small populations are prone to getting smaller.

So it's neat that Lord picked an American chaffseed.

Wednesday, May 15, 2013

An introduced invasive - in 1710

Patrick and I have gone through some of John Lawson's specimens - so far we've done determinations on his specimens in H.S. 158 and H.S. 145. These are intriguing because they were collected in 1710 or earlier (couldn't have been later, because Lawson was killed by Indians in 1711 - more on that in a bit). That was long before major European settlement in the Carolinas, more than a decade earlier than Mark Catesby. Lawson wrote a really great book about his adventures, A New Voyage to Carolina, which describes his fun with native Americans after most of them had died from smallpox but before they disappeared as a significant social force in the area. (Many thanks to UNC for digitizing this book!)

Anyway, Lawson was kicking around the Carolinas EARLY. The Lords Proprietors didn't get going with the Province of Carolina until 1663. Charleston, SC was founded in 1670. (This would be a great time to review my Restoration history - you known, when Charles II took the monarchy back in the wake of Oliver Cromwell's death.) Lawson set out for the Carolinas as an explorer, mainly because he heard that Carolina was the best place to go, and spent the next decade traveling around the countryside. His writing displays enthusiasm for his surroundings, keen observation of both natural history and human interactions, and a good sense of humor at said interactions. Also, his descriptions of animals combine observations on their physique and behavior with culinary notes. His book was a bestseller in Europe and persuaded many would-be settlers to follow Lawson into the wilds of Carolina.

Because Carolina was still wild when Lawson was there. There were some settlements, and some farms, but much of his food on his journey came from native Americans who were hunting and gathering wild foods. Not many Europeans had yet arrived in this area.

So imagine my surprise to find a specimen of Rumex crispus, curly dock, in his collection! (It's on H.S. 142 f. 62.) He (or someone) even wrote a note on it - "Wild dock a sorrell, Trout River June 20th 1710, vid with Leed[?]"(Lawson's handwriting is a bit difficult for me to decipher. "Vid" means "saw", and I think he is saying that he saw this plant with a man named Leed, or perhaps Lord.) The remark about "sorrell" is correct, as all the members of the genus Rumex are commonly called docks or sorrels.

This plant is native to Eurasia. It's currently present in every state in the U.S., and most of the world too. North Carolina now considers it one of the most troublesome invasive weeds in the state. The seeds get into agricultural seeds and they stick to clothing. So how did the darn thing get to the Trout River by 1710? Did some Englishman go walking in the countryside and then board a ship without washing his trousers? Did someone carefully save some seeds to plant in the New World, as a healthful taste of home?

In any case, that sure was fast. People move, and plants go with.

Catesby collected a bunch of introduced plants 13 years after Lawson. In a couple of weeks I'm going to the Sloane to photograph more plants collected between 1700 and 1710. We shall see how much of old Europe had managed to establish itself in North America by that point.

Oh, Lawson's death? Well, in his own book, Lawson describes a method of torture used by Indians in which they would stick a victim full of pine splinters and then set him on fire, to dance to their delight. Lawson was captured by the Tuscorora Indians in 1711 and apparently put to death, though no one knows exactly how this occurred. Lawson's friend Christopher Gale claimed that he died according to the pattern he had himself described. Qui sait?



Wednesday, May 8, 2013

Animals in the Herbarium

If you've ever been snorkling or scuba diving in the Caribbean, you will have noticed waving fields of things that look for all the world like plants. They grow out of the sandy or coral bottom, they are branched, and they sway gracefully in the current.

Plants they are not, though. You are looking at animals called gorgonians, also known as sea fans or sea whips. They're related to coral. (Sorry for citing to Wikipedia. Wikipedia is a good reference!)

What makes them animals and not plants? Among other things, they can't make their own food. They have to catch plankton and eat that. (Actually, lots of gorgonians do have symbiotic relationships with photosynthetic algae that produce some food for them, but in no sense are gorgonians plants.)

When Mark Catesby visited the Bahamas, he had no way of knowing that the sea fans he saw were not plants. They sure look plant-like! So he collected a gorgonian, and sent it off to London with his other herbarium specimens. That is why there are animals in his herbarium at Oxford.