Cedar Confusion

This is a guest post by Jeremiah Sandler. Words by Jeremiah. Photos by Daniel Murphy (except where noted).

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What makes a cedar a cedar?

I recently asked this question to a professor of mine because I kept hearing individuals in the field refer to many different species as “cedars”. It was puzzling to me because, being the taxonomy-nerd that I am, most of these plants are in entirely different plant families but still called the same thing. Yes, sometimes common names overlap with one another regionally; avoiding that mix up is the purpose of binomial nomenclature in the first place! So, what gives?! Why are 50+ different species all called cedars?

This professor is a forester, not a botanist. He told me the word “cedar” describes the wood. Turns out, after some research and conversation, that’s all there was to it. As defined by Google, a cedar is:

Any of a number of conifers that typically yield fragrant, durable timber, in particular.

Cedar wood is a natural repellent of moths, is resistant to termites, and is rot resistant. A good choice of outdoor lumber.

I was hoping to find either a phylogenetic or taxonomic answer to what makes a cedar a cedar. I didn’t. Taxonomic relationships between organisms are one of the most exciting parts of biology. Thankfully, some solace was found in the research:

There are true cedars and false cedars.

True cedars are in the family Pinaceae and in the genus Cedrus. Their leaves are short, evergreen needles in clusters. The female cones are upright and fat, between 3 – 4 inches long. Their wood possesses cedar quality, and they are native to the Mediterranean region and the Himalayas.

False cedars are in the family Cupressaceae, mostly in the following genera: Calocedrus, Chamaecyparis, Juniperus, and Thuja. Their leaves are scale-y, fan-like sprays. Female cones are very small, about half an inch long, and remain on the tree long after seed dispersal. The bark is often both reddish and stringy or peely. Their wood possesses cedar quality. It is easy to separate them from true cedars, but less obvious to tell them from one another. These false cedars are native to East Asia and northern North America.

I couldn’t do away with the umbrella term “cedar.” Every naturalist can agree that one of the most pleasurable things while outdoors looking at plants is identifying them. I have set a new objective to correctly identify and differentiate between all of the cedars and false cedars, rather than simply calling them cedars. I guess I’m just fussy like that.

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What Is a Plant, and Why Should I Care? part one

I want to tell the story of plants. In order to do that, I suppose I will need to research the 4 billion year history of life on earth. And so I am. Apart from satiating my own curiosity, studying and telling the story of plants advances me towards my goal of creating a series of botany lesson themed posts. Botany 101 and beyond, if you will. An ambitious project, perhaps, but what else am I going to do with my time?

So what is a plant anyway? We all know plants when we see them, but have you ever tried to define them? They are living beings, but they are not animals. They are stationary – rooted in the ground, usually. Most of them are green, but not all of them. They photosynthesize, which means they use water, carbon dioxide collected from the atmosphere, and energy harvested from the sun to make food for themselves. No animal can do that (okay…a few sort of can). They reproduce sexually, but many can also reproduce asexually. They are incredibly diverse. Some grow hundreds of feet into the air. Some barely reach more than a few centimeters off the ground at maturity. They have discernible parts and pieces, but they can also lose parts and pieces and then grow them back. There aren’t many animals that can do that. They have been on this planet for hundreds of millions of years, colonizing land millions of years before animals. Plants helped pave the way, and if it weren’t for plants, animals may not have stood a chance.

I don’t mean to pick on animals, it’s just that for a long time, humans grouped living things into just two kingdoms: Plantae and Animalia. Stationary things that appeared to be rooted to the ground or some other surface were classified as plants. Green things that lived in the water were also considered plants. Thus, lichens, fungi, algae, and everything we consider to be a plant today were placed in kingdom Plantae. Everything else was placed in kingdom Animalia. This, of course, was before much was known about microorganisms.

Dichotomous classification was reconsidered as we learned more about the diversity of organisms in each kingdom, particularly as the theory of evolution came into play and microscopes allowed us to observe single celled organisms and chromosomes. Eventually, fungi was awarded its own kingdom, which includes lichens – organisms composed of both fungi and photosynthetic species but classified according to their fungal components. Most of the algae was placed in a kingdom called Protista, a hodgepodge group of unicellular and unicellular-colonial organisms, some of which are animal-like and some of which are plant-like. Two kingdoms were also formed for prokaryotic organisms (organisms with cells that lack membrane bound organelles): Bacteria and Archaea.

Illustration of one current itteration of kingdom classification system (illustration credit: wikimedia commons)

Taxonomic kingdoms as we currently consider them (illustration credit: wikimedia commons)

In short, the answer to what is a plant seems to be whatever organisms humans decide to put in kingdom Plantae. One problem with this answer is that some chose to include certain species of algae and others don’t. But why is that? It has to do with how plants evolved and became photosynthetic in the first place.

Microorganisms developed the ability to photosynthesize around 3.5 billion years ago; however, the photosynthetic process that plants use today appeared much later – around 2.7 billion years ago. It evolved in an organism called cyanobacteria – a prokaryote. Eukaryotic organisms were formed when one single cell organism was taken inside another single cell organism, a process known as symbiogenesis. In this case, cyanobacteria was taken up and the eukaryotic organisms known today as algae were formed. The incorporated cyanobacteria became known as chloroplasts.

Not all algae species went on to evolve into plants. A group known as green algae appears to be the most closely related to plants, and a certain subset of green algae colonized the land and evolved into modern day plants (also known as land plants). That is why some taxonomists choose to include green algae in the plant kingdom, excluding all other types of algae.

Common stonewort (Chara vulgaris, a species of green algae (photo credit: www.eol.org)

Common stonewort, Chara vulgaris, a species of green algae (photo credit: www.eol.org)

The term land plants refers to liverworts, hornworts, mosses, ferns, fern allies, gymnosperms, and flowering plants – or in other words, all vascular and non-vascular plants. Another all encompassing term for this large group of organisms is embryophytes (embryo-producing plants).

Still confused about what a plant is? Three main features can be attributed to all plants: 1. They are multicellular organisms. 2. Their cell structure includes a cell wall composed of cellulose 3. They are capable of photosynthesis. Many species of green algae are unicellular, which is an argument for leaving them out of kingdom Plantae. Certain parasitic plants like toothwort, dodder, and beech drops have lost all or most of their chlorophyll and no longer photosynthesize, but they are still plants.

Deciding what is and isn’t a plant ultimately comes down to evolutionary history and common ancestry. As Joseph Armstrong writes in his book, How the Earth Turned Green, “Our classifications of human artifacts are totally arbitrary, but to be useful scientifically our classification of life must accurately reflect groupings that resulted from real historical events, common ancestries.”

Obviously this is going to be a multi-part series, so I will have much more to tell you about plants in part two, etc. For now, this You Tube video offers a decent summary.

The Discovery of a Living Fossil

In the early 1940’s, the genus Metasequoia was only known scientifically in fossil form. It had, in its day, been a widespread genus, found commonly in many areas across the Northern Hemisphere. It thrived among the dinosaurs. However, sometime during the Pliocene, the genus was thought to have died out. Thousands of fossils were left behind, and that would have been the end of the story had a member of its genus not been discovered still alive in a Chinese province later that decade. Its discovery is easily one of the greatest botanical stories of the 20th century, fascinating in its own right. The circumstances surrounding its scientific description, as it turns out, are equally interesting.

In the January 2016 issue of Landscape Architecture Magazine, Kyna Rubin details the event in an article entitled The Metasequoia Mystery. It’s the type of story that you almost need a crazy wall to sort out. A broad cast of characters interacted at various levels in order to make this profound discovery during a tumultuous time when the world was at war and China was being invaded by Japan.

Speaking of Japan, let’s start there. In 1941, Japanese paleobotanist, Shigeru Miki, published research describing fossils that for decades were thought to be either Sequoia or Taxodium as a new genus, Metasequoia. As Rubin points out, due to the war, “not every Chinese botanist would have had access to recent international research, let alone articles by botanists of an enemy country.” This could explain why in 1943 when Zhan Wang – a professer of forestry at Beijing University and the forest administrator for the Ministry of Agriculture and Forestry – was introduced to a living Metasequoia by an old classmate and local villagers in the Hubei Province, he wasn’t sure what he was looking at.

The tree was obviously important to the local people. They called it shuisa (water fir) and had built a shrine around it. Wang collected several branches and some cones that had fallen on a rooftop. At the time he identified it as Glyptostrobus pensilis (water pine), a tree common to the area; but he may have wondered if this was correct.

Eventually Wang’s samples and the details of his collection were brought to the attention of Wanjun Zheng, a dendrologist at the National Central University. Intrigued, Zheng sent his graduate student, Jiru Xue, to collect more samples from the same tree that Wang had encountered. These samples were more complete, and when they were presented to Xiansu Hu – the director of Fan Memorial Institute of Biology in Beijing – the mystery was solved. Hu had access to Miki’s research and concluded that what they had was a living fossil.

In 1948, Hu and Zheng published a paper describing the species and giving it the official name, Metasequoia glyptostroboides. The discovery ignited the botanical community as well as the general public, and soon seeds of what became commonly known as dawn redwood were being disseminated across the globe. Unfortunately, Wang’s contribution was not mentioned in the original paper, and the exact account of the discovery became convoluted.

photo credit: wikimedia commons

Dawn redwood (Metasequoia glytostroboides) is a deciduous, medium to large tree. Its cones are round and about 1 inch long. Its leaves are oppositely arranged and have a feather-like appearance. Its bark is fibrous, stringy, and red-brown to gray in color.  (photo credit: wikimedia commons)

At some point, a discussion between Zheng and a forester named Duo Gan (also known as Toh Kan) revealed that Gan had come across the tree in 1941, but he did not make any collections. Despite Zheng learning of Gan’s encounter after Zheng and Hu’s original paper had been published, Gan’s story became prominent, further obscuring the role that Wang played.

It’s important to note that none of Wang’s original collections were used as the type specimen – the particular specimen of an organism to which the scientific name is formally attached and is referred to in the scientific literature. The type specimen was collected by Xue. This is not uncommon, as initial collections may not always be in the best condition and may not include all the parts and pieces necessary to identify and describe a new species. But, as Rubin notes, “it was Wang’s specimens [that Zheng and others] had first examined and those specimens brought the tree to their attention to begin with.” So Wang’s contribution is an important part of the story.

Thanks to Wang’s former students, his role in the discovery has received greater exposure. Jinshuang Ma in particular has made it his mission to highlight the part that Wang played in the event. Apart from maintaining a website all about Metasequoia, Ma also spent several years searching for a lost herbarium specimen collected by Wang, which he found in an abandoned herbarium in Nanjing. You can read about his find in this article from the August 2003 issue of the journal Taxon. (Ma’s well researched summary of the events surrounding the Metasequoia discovery is also worth reading.)

Failure to acknowledge Wang’s contribution (at least initially) perhaps didn’t make waves outside of China, but in Rubin’s words, “the omission of Wang’s contribution sparked immediate hullabaloo inside China’s botanical circles in the late 1940’s.” Power and class differences likely played a big role. Hu and Zheng were established scholars that had received their educations in the United States and France respectively. Wang was young, from a remote village, and had not studied abroad. While Wang “went on to become one of China’s most distinguished forestry experts and botanists,” he was early in his career at the time of the Metasequoia discovery.

A deep respect for the elders in his field may be the reason that Wang’s students claim that he “never complained” about his treatment. His students go on to say that Wang “was not interested in personal gain,” and instead was simply satisfied to see that Metasequoia “was now growing successfully all over the world and was better protected.” It is listed as endangered on the IUCN Red List and would likely be extinct in its shrunken native range had awareness of its existence not come about when it did.

Fossil of Metasequoia occidentalis - photo credit: wikimedia commons

Fossil of Metasequoia occidentalis – photo credit: wikimedia commons

There are plenty of other interesting details to this story. Read the full article and check out the links on metasequoia.org to learn more. The account of Jiru Xue (also known as Hsueh Chi-Ju), the graduate student who collected the type specimens, is particularly interesting. Suprisingly, the tree Wang and Xue took their collections from is still alive today and is estimated to be over 400 years old.

Other longform article reviews on Awkward Botany:

Year of Pollination: The Anatomy of a Bee

A greater appreciation for pollinators can be had by learning to identify them – being able to tell one from another and calling them by name. Anyone can tell a butterfly from a bee, but how about telling a sweat bee from a leafcutter bee? Or one species of sweat bee from another species of sweat bee? That takes more training. This is where knowing the parts of a bee becomes important.

I am new to learning the names of pollinators. I’ve been learning the names of plants for many years now (and I still have a long way to go), but my knowledge of insect identification is largely limited to one entomology course I took in college and the occasional reading about insects in books and magazines. So, this post is just as much for me as it is for anybody else. It also explains why it is brief and basic. It’s for beginners.

This first illustration is found in the book Pollinators of Native Plants by Heather Holm. The book starts with brief overviews of pollination, pollinators, and pollinator conservation, but then spends nearly 200 pages profiling specific plants and describing the particular species of pollinating insects that visit them. The photos of the insects are great and should be very useful in helping to identify pollinators.

bee anatomy_pollinators of native plants book

This next illustration is from the book California Bees and Blooms by Gordon W. Frankie, et al. The title is a bit deceptive because much of what is found in this book is just as applicable to people outside of California as it is to people within. There is some discussion about plants and pollinators specific to California and the western states, but there is also a lot of great information about bees, flowers, and pollination in general, including some great advice on learning to identify bees. The book includes this basic diagram, but it also provides several other more detailed illustrations that help further describe things like mouth parts, wings, and legs.

bee anatomy_california bees and blooms book

As part of their discussion on identifying bees, the authors of California Bees and Blooms offer these encouraging and helpful words to beginners like me: “Even trained taxonomists must examine most bees under a microscope to identify them to species level, but knowing the characteristics to look for can give you a pretty good idea of the major groups and families of bees that are visiting your garden. These include size, color, and features of the head, thorax, wings, and abdomen.”

If you would like to know more about the pollinators found in your region, including their names, life history, and the plants they visit, books like the aforementioned are a good start. Also, find yourself a copy of a field guide for the insects in your area and a good hand lens. Then spend some time outside closely and quietly observing the busy lives of the tiny things around you. I plan to do more of this sort of thing, and I am excited see what I might find. Let me know what you find.

Here are a few online resources for learning more about bee anatomy and bee identification:

Other “Year of Pollination” Posts: