In Praise of Poison Ivy

This is a guest post by Margaret Gargiullo. Visit her website, Plants of Suburbia, and check out her books for sale on Amazon.

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No one seems to like Toxicodendron radicans, but poison ivy is an important plant in our urban and suburban natural areas. Poison ivy (Anacardiaceae, the cashew family) is a common woody vine, native to the United States and Canada from Nova Scotia to Florida, west to Michigan and Texas. It is also found in Central America as far south as Guatemala. It is all but ubiquitous in natural areas in the Mid-Atlantic United States. It has been recorded in over 70 wooded parks and other natural areas in New York City.

Leaflets of three? Let if be. Poison ivy (Toxicodendron radicans). photo credit: wikimedia commons

Leaflets of three? Let if be. Poison ivy (Toxicodendron radicans) – photo credit: wikimedia commons

Poison ivy does have certain drawbacks for many people who are allergic to its oily sap. The toxins in poison ivy sap are called urushiols, chemicals containing a benzene ring with two hydroxyl groups (catechol) and an alkyl group of various sorts (CnHn+1).

These chemicals can cause itching and blistering of skin but they are made by the plant to protect it from being eaten by insects and vertebrate herbivores such as rabbits and deer.

Poison ivy is recognized in summer by its alternate leaves with three, shiny leaflets and by the hairy-looking aerial roots growing along its stems. In autumn the leaves rival those of sugar maple for red and orange colors. Winter leaf buds are narrow and pointed, without scales (naked). It forms extensive colonies from underground stems and can cover large areas of the forest floor with an understory of vertical stems, especially in disturbed woodlands and edges. However, It generally only blooms and sets fruit when it finds a tree to climb. When a poison ivy stem encounters a tree trunk, or other vertical surface, it clings tightly with its aerial roots and climbs upward, reaching for the light (unlike several notorious exotic vines, it does not twine around or strangle trees). Once it has found enough light, it sends out long, horizontal branches that produce flowers and fruit.

Flowers of poison ivy are small and greenish-white, not often noticed, except by the honeybees and native bees which visit them for nectar and exchange pollen among the flowers. Honey made from poison ivy nectar is not toxic. Fruits of poison ivy are small, gray-white, waxy-coated berries that can remain on the vine well into winter. They are eaten by woodpeckers, yellow-rumped warblers, and other birds. Crows use poison ivy berries as crop grist (instead of, or along with, small stones) and are major dispersers of the seeds.

The fruits of poison ivy (Toxicodendron radicans) - photo credit: Daniel Murphy

The fruits of poison ivy (Toxicodendron radicans) – photo credit: Daniel Murphy

It is as a ground cover that poison ivy performs its most vital functions in urban and suburban woodlands. It can grow in almost any soil from dry, sterile, black dune sand, to swamp forest edges, to concrete rubble in fill soils, and along highways. It enjoys full sun but can grow just fine in closed canopy woodlands. It is an ideal ground cover, holding soil in place on the steepest slopes, while collecting and holding leaf litter and sticks that decay to form rich humus. It captures rain, causing the water to sink into the ground, slowing runoff, renewing groundwater, filtering out pollutants, and helping to prevent flooding.

Poison ivy is usually found with many other plants growing up through it – larger herbs, shrubs, and tree seedlings that also live in the forest understory. It seems to “get along” with other plants, unlike Japanese honeysuckle or Asian bittersweet, which crowd out or smother other plants. Poison ivy is also important as shelter for birds and many invertebrates.

While those who are severely allergic to poison ivy have reason to dislike and avoid it, Toxicodendron radicans has an important place in our natural areas. No one would advocate letting it grow in playgrounds, picnic areas, or along heavily used trail margins, but it belongs in our woods and fields and should be treated with respect, not hatred. Recognize it but don’t root it out.

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Further Reading: Uva, R. H., J.C. Neal and J. M. DiTomaso. 1997. Weeds of the Northeast. Comstock Publishing. Ithaca, NY.

This piece was originally published in the New York City Dept. of Parks & Recreation, Daily Plant.

Alien Plant Invasions and the Extinction Trajectory

One of the concerns about introduced species becoming invasive is that they threaten to reduce the biodiversity of the ecosystems they have invaded. They do this by spreading rampantly, using up resources and space, altering ecosystem functions, and ultimately pushing other species out. In the case of certain invasive animals, species may be eliminated via predation; but plants don’t eat each other (generally), so if one plant species is to snuff out another plant species it must use other means. Presently, we have no evidence that a native plant species has been rendered extinct solely as a result of an invasive plant species. That does not mean, however, that invasive plants are not doing harm.

In a paper published in AoB Plants in August 2016, Paul O. Downey and David M. Richardson argue that, when it comes to plants, focusing our attention on extinctions masks the real impact that invasive species can have. In general, plants go extinct more slowly than animals, and it is difficult to determine that a plant species has truly gone extinct. Some plants are very long-lived, so the march towards extinction can extend across centuries. But the real challenge – after determining that there are no above-ground signs of life – is determining that no viable seeds remain in the soil (i.e. seed bank). Depending on the species, seeds can remain viable for dozens (even hundreds) of years, so when conditions are right, a species thought to be extinct can emerge once again. (Consider the story of the Kankakee mallow.)

On the other hand, there is plenty of evidence that invasive plant species have had significant impacts on certain native plant populations and have placed such species on, what Downey and Richardson call, an extinction trajectory. It is this trajectory that deserves our attention if our goal is to save native plant species from extinction. As described in the paper, the extinction trajectory has six steps – or thresholds – which are defined in the infographic below:

6-threshold-extinction-trajectory

Downey and Richardson spend a portion of the paper summarizing research that demonstrates how invasive plants have driven native plants into thresholds 1-3, thereby placing them on an extinction trajectory. In New Zealand, Lantana camara (introduced from the American tropics) creates dense thickets, outcompeting native plants. Researchers found that species richness of native plants declined once L. camara achieved 75% cover in the test sites. In the U.S., researchers found reduced seed set in three native perennial herbs as a result of sharing space with Lonicera mackii (introduced from Asia), suggesting that the alien species is likely to have a negative impact on the long-term survivability of these native plants. Citing such research, Downy and Richardson conclude that “it is the direction of change that is fundamentally important – the extinction trajectory and the thresholds that have been breached – not whether a native plant species has actually been documented as going extinct due to an alien plant species based on a snapshot view.”

Introduced to New Zealand from the American tropics, largeleaf lantana (Lantana camara) forms dense thickets that can outcompete native plant species. (photo credit: wikimedia commons)

Introduced to New Zealand from the American tropics, largeleaf lantana (Lantana camara) forms dense thickets that can outcompete native plant species. (photo credit: wikimedia commons)

In support of their argument, they also address problems with the way some research is done (“in many instances appropriate data are not collected over sufficiently long periods,” etc.), and they highlight the dearth of data and research (“impacts associated with most invasive alien plants have not been studied or are poorly understood or documented”). With those things in mind, they make recommendations for improving research and they encourage long-term studies and collaboration in order to address the current “lack of meta analyses or global datasets.” A similar recommendation was made in American Journal of Botany in June 2015.

The language in this report makes it clear that the authors are responding to a certain group of people that have questioned whether or not the threat of invasive plants has been overstated and if the measures we are taking to control invasive plants are justified. The following cartoon that appeared along with a summary of the article way oversimplifies the debate:

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Boy: There are no studies that show weeds cause native plants to go extinct, thus we should not control them. Plant: If we wait until then, we’ll all be gone!!! Girl: Just because no one has demonstrated it does not mean that extinctions do not occur. The problem is not overstated!

It seems to me that a big part of why we have not linked an invasive plant species to a native plant species extinction (apart from the difficulty of determining with certainty that a plant has gone extinct) is that extinctions are often the result of a number of factors. The authors do eventually say that: “it is rare that one threatening process in isolation leads to the extinction of a species.” So, as much as it is important to fully understand the impacts that invasive plant species are having, it is also important to look at the larger picture. What else is going on that may be contributing to population declines?

Observing invaded plant populations over a long period seems like our best bet in determining the real effects that invasive species are having. In some cases, as Downey and Richardson admit, “decreased effects over time” have been documented, and so “the effects [of invasive species] are dynamic, not static.” And speaking of things that are dynamic, extinction is a dynamic process and one that we generally consider to be wholly negative. But why? What if that isn’t always the case? Extinctions have been a part of life on earth as long as life has been around. Is there anything “good” that can come out of them?

Introducing Invasive Species

The terms “invasive” or “invasive species” get thrown around a lot. They are frequently used to describe anything that is “misbehaving,” or acting in a way that doesn’t fit our idealized vision for how a landscape should look and function. Oftentimes a species that is introduced (by humans) or is not native to an area automatically gets labeled invasive, even if it isn’t acting aggressively or having any sort of dramatic impact on the ecosystem. It is an alien species in an alien environment; it has invaded, therefore it is invasive.

image credit: cartoon movement

image credit: cartoon movement

Determining what is actually invasive in what location and at what time is much more complex than that. We do our best to understand the natural features and functions of ecosystems, and we single out any species, whether introduced or not, that is acting to upset things. That species is considered invasive and, if the goal is to restore the natural balance, it must be controlled. To what degree a species should be controlled depends on the degree that it is upsetting things. Ultimately, it comes down to human judgement. Hopefully that judgement is based on the best available evidence, but that isn’t always the case.

But we are getting ahead of ourselves. What I mostly want to accomplish with this post is to introduce the concept of invasive species and point you to a selection of resources to learn more about them. I defined invasive species in a post I wrote back in August 2015, so I will repeat myself here:

“Invasive species” is often used inappropriately to refer to any species that is found outside of its historic native range (i.e. the area in which it evolved to its present form). More appropriate terms for such species are “introduced,” “alien,” “exotic,” “non-native,” and “non-indigenous.” The legal definition of an invasive species (according to the US government) is “an alien species that does or is likely to cause economic or environmental harm or harm to human health.” Even though this definition specifically refers to “alien species,” it is possible for native species to behave invasively.

These terms refer not just to plants but to all living organisms. The term “noxious weed,” on the other hand, is specific to plants. A noxious weed is a plant species that has been designated by a Federal, State, or county government as “injurious to public health, agriculture, recreation, wildlife, or property.” A “weed” is simply a plant that, from a human perspective, is growing in the wrong place, and any plant at any point could be determined to be a weed if a human says so.

Invasive species are easily one of the most popular ecological and environmental topics, and resources about them abound – some more credible than others. Here is a list of places to start:

That should get you started. There are, of course, numerous books on the subject, as well as a number of peer-reviewed journals dedicated to biological invasions. You should also be aware that IUCN maintains a list of the Top 100 World’s Worst Invasive Species and that there is a National Invasive Species Awareness Week, which is quickly approaching. This episode of Native Plant Podcast with Jamie Reaser (executive director of National Invasive Species Council) offers an informative discussion about invasive species, and a search for “invasive species” on You Tube brings up dozens of results including this brief, animated video:

 

I want to believe that we are doing the right thing when we make concerted efforts to remove invasive species and restore natural areas, but I’m skeptical. The reason why I have chosen to spend an indefinite amount of time exploring the topic of invasive species is because I truly want us to get it right. Yet I don’t even know that there is a “right.” It seems to me that there are endless trajectories – each one of them addressing different objectives and producing different outcomes. In a way we are playing God, regardless of which approach we take. We are making decisions for nature as if we know what’s best for it or that there even is a “best.”

Humans have had major impacts on virtually every square inch of the planet and have been placing our fingerprints on every ecosystem we touch since long before we became the humans we are today, and so it is difficult for me to envision a planet sans humans. It is also difficult for me to buy into the idea that our planet should look as though humans haven’t touched it (i.e. pristine). Because we have been touching it – for hundreds of thousands of years. Efforts to rewind time to before introductions occurred or to hold an ecosystem in stasis, securing life for only those species that “belong” there, seem noble yet fanciful at best and misguided, arrogant, and fruitless at worst.

To be the best conservationists we can be, we probably need to find a middle ground regarding invasive species – not a deter and eliminate at all costs approach, but also not a complete surrender/all are welcome and all can stay stance. Somewhere in between seems reasonable, acknowledging that the strategy taken will be different every time based on the location, the species in question, and our objectives. Of course, none of my beliefs or opinions on this topic (or any topic for that matter) are fully formed. I am trying to do my best to maintain an open mind, seeking out the best information available and following the evidence where it takes me. A topic as complex as invasion biology, however, is never going to be easy to finalize one’s opinions on, and so this journey will be boundless. I hope you will join me.

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Last but not least, here are two articles that discuss updating our approach to dealing with invasive species:

 

2016: Year in Review

2016 was another busy year at Awkward Botany headquarters. A major highlight was the response I received from the Help Wanted announcement that I posted early last year. Several people expressed interest in writing guest posts, while several others volunteered to help out in other ways (contributing images, illustrations, logos, etc.). The offer still stands, so please be in touch if you would like to contribute in any way.

Speaking of being in touch, the comments I’ve received and the connections I’ve made through social media and beyond really add to the experience of doing this blog. Not only does it make this more of a conversation, but it is greatly motivating to know that people find this to be a valuable and entertaining resource. Thank you to all who have reached out. And thanks to silent observers as well. Let’s stay in touch.

As I have done in the past, I am including a list of some of the posts from this past year, mainly those that are part of ongoing series. Many posts don’t fall within these categories, so all others can be found in the ‘Archives’ widget on the right side of the screen.

Book Reviews:

Poisonous Plants:

Famous Botanists in History:

Drought Tolerant Plants:

Field Trips:

Ethnobotany:

Botany in Popular Culture:

Tiny Plants:

Rare and Endangered Plants

Podcast Review:

Guest Posts:

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

Along with the great guest posts, I also received Awkward Botany logos from three incredible artists/graphic designers. I loved them all, and I am very thankful for the time and talent that was spent creating them. The logos are featured below. In order of appearance they were created by Franz Anthony, Mesquite Cervino, and Mara McCall. If you have an idea for an Awkward Botany logo, please let me know. I would love to see it.

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And now a heads up…

In the coming months I plan to focus most of my posts on “weeds” and invasive species. These are topics that I have found increasingly intriguing, so I am hoping that writing a long series of posts about them will help satisfy my curiosity. This may or may not be your thing, but I hope you will stick around regardless. I plan to continue to include some guest posts, which will hopefully help break up the monotony. Also, I know I said this last year and it didn’t actually happen, but I will most likely be taking some breaks from my weekly publishing schedule in order to work on some other projects. Those projects and more will be revealed at some point in time, along with other ideas I have rolling around in my head. If the thought of me taking breaks from posting here bothers you, I invite you to join me on twitter and tumblr, where I will continue to post random things regularly.

Until then, I wish you all a splendid 2017. It should be an interesting one, so buckle up.

Yucca in the snow at Idaho Botanical Garden in Boise, Idaho

Yucca in the snow at Idaho Botanical Garden in Boise, Idaho

Ethnobotany: The Henna Tree

A hair dye used in pre-dynastic Egypt is still used today. This enduring plant-based dye has found its way into a great number of cultures going back as long as 6000 years. Its popularity is thanks in part to the broad distribution of the plant itself, but is largely a result of the diverse religious traditions that have incorporated the dye into their rituals. The plant’s use in such traditions continues, while its current popularity extends well beyond that.

Lawsonia inermis is the only species in its genus. It is a member of the plant family, Lythraceae, a family that includes crepe myrtles (Lagerstroemia), cigar plants (Cuphea), and pomegranates (Punica). L. inermis has many common names, including mignonette tree and Egyptian privet. It is most commonly known as, henna, a term that refers to the plant itself, the dye derived from the plant, and the body art made using the dye.

Henna is a shrub or small tree that reaches a height of about 6 meters. The leaves are smooth, elliptically-shaped, and oppositely-arranged on branches that are spine-tipped. Inflorescences are many-branched with numerous small, fragrant flowers. The most prominent features of the flowers are four sepals forming a bowl shape and several white to red stamens reaching towards the sky. The fruits are small, round, brown capsules full of tiny seeds. Henna thrives in dry environments with poor soil; however, it does not tolerate frost. It occurs in tropical and subtropical regions of Africa, western and southern Asia, and northern Australasia. Cultivation by humans has broadened its distribution well beyond its original boundaries.

Lawsonia inermis - photo credit: wikimedia commons

Lawsonia inermis – photo credit: wikimedia commons

Henna has been used to dye the skin, nails, and hair of women and men in many cultures and religions across its area of natural distribution and beyond. Its use has been especially common among women as part of fertility and marriage celebrations. The plant’s dye may have been first discovered around the mouths of browsing livestock – the persistent red-orange color having the appearance of blood. Henna plants are drought-deciduous, but they burst back to life when rain returns, producing abundant new branches, leaves, and flowers. This period of growth coincides with celebrations of marriage and fertility and may explain why it found common use in such traditions.

Dyes are made by crushing dried leaves into a fine powder and then mixing it into a paste using water, lemon juice, tea, or other liquids. A soap or shampoo is produced when henna is mixed with plant extracts containing saponin, and the addition of certain essential oils can enhance the performance of the dye. The compound in the leaves that produces the red-orange dye is called lawsone and is found in varying concentrations depending on the conditions in which the plant was grown. High heat and low soil moisture is said to produce the highest levels of lawsone. More than just a dye, lawsone also has antifungal properties and strongly absorbs UV light, thus its application is beyond cosmetic as it has proven useful against fungal diseases like athlete’s foot and as a sunscreen. And that’s just the beginning.

Henna applied to hair - photo credit: wikimedia commons

Henna applied to hair – photo credit: wikimedia commons

A study published in the Journal of Ethnopharmacology by Semwal, et al. reveals that nearly a hundred phytoconstituents (or “biologically active compounds”) have been isolated from all parts of the henna plant. Henna has long been used medicinally to treat a wide range of ailments, and while it may not be an effective treatment for all that it has been historically used for, it has been found effective for certain things and has great potential for further use.

In the paper, the authors review dozens of studies exploring the many “biological activities” that henna is claimed to have, which include “antifungal, antibacterial, virucidal, antiparasitic, anti-inflammatory, analgesic, and anticancer properties,” etc. Research into these properties is limited and has been “complicated and hampered” by the widespread practice of adding other ingredients (some of them harmful) to henna products. In order for henna’s “therapeutic potential” to be properly explored, the authors advise identifying and standardizing the plant’s active components.

Henna continues to be used in cultures across the world and is particularly prominent in Hinduism and Muslim practices. It is most commonly used to dye hair and create temporary body art (also known as mehndi). Henna art is often applied to the hands and feet, where the skin is thick and absorbs more of the lawsone. It is applied as a paste and either squeezed through a plastic cone or syringe or painted on with a stick or brush. The longer the paste is left on, the darker the stain will be. After a week or so the henna begins to fade as old skin cells slough off.

photo credit: wikimedia commons

photo credit: wikimedia commons

In ancient cultures, henna was thought to ward off the Evil Eye as well as bring good luck and blessings, a trait known as baraka. This belief is part of the reason why henna was incorporated into marriage ceremonies and other religious rituals. Because of henna’s antifungal, analgesic, and anti-inflammatory properties, etc., real benefits are seen when henna is applied to various parts of the body. Semwal, et al. argue that a scientific understanding was not necessary for “recognition of benefit.” Today however, “scientific investigation and quantification of henna’s ‘baraka’ should expand and optimize these traditional qualitative understandings.”

Because of henna’s widespread use and long history, it is not feasible to fit henna’s entire story into a single blog post. Henna is worth exploring on your own. Here are a few more interesting tidbits for now. In Semwal, et al.’s summary there is a mention of henna twigs being “rubbed over the teeth for effective dental self-care” – something to keep in mind in case you find yourself without a toothbrush, and a henna plant happens to be nearby. A paper published in a 1993 issue of Thaiszia – Journal of Botany discusses the historical use of henna in the Balkans. Slavs in the area reportedly treated typhoid fever using a mixture of henna and “the juice of twenty heads of garlic” heated in water. Finally, henna has been used to dye many things, including leather, cloth, and animal fur. Persians have long used henna to dye the manes, tales, and hooves of their horses and other animals. A practice that continues today.

More Ethnobotany Posts:

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

What Is a Plant?

Part one and two of this series have hopefully answered that.

Why should you care?

Part three offered a pretty convincing answer: “if it wasn’t for [plants], there wouldn’t be much life on this planet to speak of.”

Plants are at the bottom of the food chain and are a principle component of most habitats. They play major roles in nutrient cycling, soil formation, the water cycle, air and water quality, and climate and weather patterns. The examples used in part three of this series to explain the diverse ways that plants provide habitat and food for other organisms apply to humans as well. However, humans have found numerous other uses for plants that are mostly unique to our species – some of which will be discussed here.

But first, some additional thoughts on photosynthesis. Plants photosynthesize thanks to the work accomplished by very early photoautotrophic bacteria that were confined to aquatic environments. These bacteria developed the metabolic processes and cellular components that were later co-opted (via symbiogensis) by early plants. Plants later colonized land, bringing with them the phenomena of photosynthesis and transforming life on earth as we know it. Single-celled organisms started this whole thing, and they continue to rule. That’s just something to keep in mind, since our focus tends to be on large, multi-cellular beings, overlooking all the tiny, less visible beings at work all around us making life possible.

Current representation of the tree of life. Microorganisms clearly dominate. (image credit: nature microbiology)

Current representation of the tree of life. Microorganisms clearly dominate. (image credit: nature microbiology)

Food is likely the first thing that comes to mind when considering what use plants are to humans. The domestication of plants and the development of agriculture are easily among the most important events in human history. Agricultural innovations continue today and are necessary in order to both feed a growing population and reduce our environmental impact. This is why efforts to discover and conserve crop wild relatives are so essential.

Plants don’t just feed us though. They house us, clothe us, medicate us, transport us, supply us, teach us, inspire us, and entertain us. Enumerating the untold ways that plants factor in to our daily lives is a monumental task. Rather than tackling that task here, I’ll suggest a few starting points: this Wikipedia page, this BGCI article, this Encylopedia of Life article, and this book by Anna Lewington. Learning about the countless uses humans have found for plants over millennia should inspire admiration for these green organisms. If that admiration leads to conservation, all the better. After all, if the plants go, so do we.

Humans have a long tradition of using plants as medicine. Despite all that we have discovered regarding the medicinal properties of plants, there remains much to be discovered. This one of the many reasons why plant conservation is so important. (photo credit: wikimedia commons)

Humans have a long tradition of using plants as medicine. Despite all that we have discovered regarding the medicinal properties of plants, there remains much to be discovered. This is one of the many reasons why plant conservation is imperative. (photo credit: wikimedia commons)

Gaining an appreciation for the things that plants do for us is increasingly important as our species becomes more urban. Our dense populations tend to push plants and other organisms out, yet we still rely on their “services” for survival. Many of the functions that plants serve out in the wild can be beneficial when incorporated into urban environments. Plants improve air quality, reduce noise pollution, mitigate urban heat islands, help manage storm water runoff, create habitat for urban wildlife, act as a windbreak, reduce soil erosion, and help save energy spent on cooling and heating. Taking advantage of these “ecosystem services” can help our cities become more liveable and sustainable. As the environmental, social, and economic benefits of “urban greening” are better understood, groups like San Francisco’s Friends of the Urban Forest are convening to help cities across the world go green.

The importance of plants as food, medicine, fuel, fiber, housing, habitat, and other resources is clear. Less obvious is the importance of plants in our psychological well being. Numerous studies have demonstrated that simply having plants nearby can offer benefits to one’s mental and physical health. Yet, urbanization and advancements in technology have resulted in humans spending more and more time indoors and living largely sedentary lives. Because of this shift, author Richard Louv and others warn about nature deficit disorder, a term not recognized as an actual condition by the medical community but meant to describe our disconnect with the natural world. A recent article in BBC News adds “nature knowledge deficit” to these warnings – collectively our knowledge about nature is slipping away because we don’t spend enough time in it.

The mounting evidence for the benefits of having nature nearby should be enough for us to want to protect it. However, recognizing that we are a part of that nature rather than apart from it should also be emphasized. The process that plants went through over hundreds of millions of years to move from water to land and then to become what they are today is parallel with the process that we went through. At no point in time did we become separate from this process. We are as natural as the plants. We may need them a bit more than they need us, but we are all part of a bigger picture. Perhaps coming to grips with this reality can help us develop greater compassion for ourselves as well as for the living world around us.

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.