A Few More Snags Near Ketchum

Nearly a year has passed since Sierra and I took a trip to Ketchum, Idaho and I reported on some of the snags we encountered there. After months without a break, we finally had the chance to get away for a few days, and since we were desperate for some time off and a change of scenery, we couldn’t turn it down. Plus, we were heading back to Ketchum, so I knew I’d get to check out a few more snags. I was stoked.

I’m obsessed with trees, and my preference is for live ones (generally speaking), but dead trees are certainly gaining in popularity. After all, a dead tree isn’t truly dead. As its corpse slowly rots, it continues to harbor and support life inside and out in a substantial way. Forests need dead trees just as much as they need live trees. Plus, ecology aside, dead trees are no less photogenic than any other tree.

Death isn’t all bad. New life springs from decay. Given our current state of affairs, we need this reminder, and snags offer it in spades. As Sierra and I pulled up to the Apollo Creek trailhead, we looked out onto a section of forest that had clearly been ravaged by fire in the not too distant past. Acres of standing and fallen burned out trees bore witness to this fact. Yet among the dead, life flourished, as dozens of songbirds actively foraged on and around the charred trees. They were there for the insects that were feeding on the dead wood, fueling themselves for fall migration. In the spring, when the birds return, some of them may even nest in the cavities of the dead trees. They will feed again on the insects and raise up a new generation of songbirds that will do the same. In and among snags there are myriad examples just like this, showing us the countless ways in which death supports new life.

What follows is a small sampling of the snags we encountered this time around on our trip to Ketchum.

post-fire snag among many other snags

a series of cavities in a post-fire snag

snag surrounded by live trees

three new snags

fallen snag

broken snag

new tree emerging from a nurse stump

not a snag, but one of many lupines we saw flowering along Apollo Creek Trail

Flowers Growing Out of Flowers (Things Are Getting Weird Out There)

I’m sure that anyone living through the events of 2020 would agree, these are truly wild times. So, when I stumbled across some purple coneflowers that appeared to be growing flowers out of flowers, I thought to myself, “Of course! Why not!?!” The world is upside down. Anything is possible.

As it turns out, however, this phenomenon occurs more frequently than I was aware. But it’s not necessarily a good thing, particularly if you’re concerned about plant health. We’ll get to that in a minute. First, what’s going on with these flowers?

Flowers in the aster family are unique. They have the appearance of being a single flower but are actually a cluster of two types of much smaller flowers all packed in together. Purple coneflower (Echinacea purpurea) is a great example of this. Its flower heads are composed of dozens of disc flowers surrounded by a series of ray flowers. The minuscule disc flowers form the cone-like center of the inflorescence. The petals that surround the cone are individual ray flowers. This tight cluster of many small flowers (or florets) is known as a composite. Sunflowers are another example of this type of inflorescence.

Flowers are distinct organs. Not only are they the reproductive structures of flowering plants, but unlike the rest of the plant, they exhibit determinate growth. Flowers are, after all, plant shoots that have been “told” to stop growing like other shoots and instead modify themselves into reproductive organs and other associated structures. Unlike other shoots, which continue to grow (or at least have the potential to), a flower (and the fruit it produces) is the end result for this reproductive shoot. This is what is meant by determinate growth. However, sometimes things go awry, and the modified shoots and leaves that make up a flower don’t develop as expected, producing some bizarre looking structures as a result.

An example of this is a double flower. Plants with double flowers have mutations in their genes that cause disruptions during floral development. This means that their stamens and carpels (the reproductive organs of the flowers) don’t develop properly. Instead, they become additional petals or flowers, resulting in a flower composed of petals upon petals upon petals – a look that some people like, but that have virtually nothing to offer the pollinators that typically visit them. Because of their ornamental value, double-flowered varieties of numerous species – including purple coneflower – can be found in the horticultural trade.

double-flowered purple coneflower

Genetic mutations are one way that odd looking flowers come about. It is not the cause, however, of the freak flowers that I recently came across. What I witnessed was something called phyllody and was the result of an infection most likely introduced to the plant by a leafhopper or some other sap-sucking insect. Phyllody, which has a variety of causes, is a disruption in plant hormones that leads to leaves growing in place of flower parts. As a result, the flowers become sterile and green in color. In the case of purple coneflower, leafy structures are produced atop shoots arising from the middle of ray and/or disc florets. In other species, shoots aren’t visible and instead the inflorescence is just a cluster of leaves. In a sense, the reproductive shoot has returned to indeterminate growth, having switched back to shoot and leaf production.

Phyllody can have either biotic or abiotic causes. Biotic meaning infection by plant pathogens – including certain viruses, bacteria, and fungi – or damage by insects. Abiotic factors like hot weather and lack of water can result in a temporary case of phyllody in some plants. Phyllody plus a number of other symptoms made it clear that the purple coneflower I encountered had a fairly common disease known as aster yellows. This condition is caused by a bacterial parasite called a phytoplasma, and is introduced to the plant via a sap-sucking insect. It then spreads throughout the plant, infecting all parts. The phyllody was a dead give away, but even the flowers that weren’t alien-looking were discolored. The typical vibrant purple of the ray flowers was instead a faded pink color. The flowers that had advanced phyllody – along with the rest of the plant – were turning yellow-green.

This inflorescence isn’t exhibiting phyllody yet, but the purple color in the ray flowers is quickly fading.

Hundreds of plant species are susceptible to aster yellows, and not just those in the aster family. Once a plant is infected with aster yellows, it has it for good and will never grow or reproduce properly. For this reason, it is best to remove infected plants from the garden to avoid spreading the infection to other plants. As cool as the flowers may look, infected plants just aren’t worth saving.

Further Reading: 

Book Review: The Gyroscope of Life

Gyroscopes are entertaining toys and incredibly useful tools. They retain their balance and resist changes to their orientation as long as their flywheel is spinning. As the flywheel slows or stops, the gyroscope wobbles out of control and ultimately quits. Considering their design and function, it’s easy to find parallels between gyroscopes and living systems. Consistent energy inputs keep living things alive. Changes can bring imbalance; major disruptions can lead to death. There is a reason we often describe the natural world as a sort of balancing act. It is the work of an ecologist to make sense of this balancing act. The better we understand it, the more equipped we are to protect it and operate responsibly within it.

It is through this lens that David Parrish writes about the biological world in The Gyroscope of Life, a book that Parrish refers to as “a love song to the field of biology.” Parrish has spent much of his life observing and studying the natural world and, as professor emeritus of Crop and Soil Environmental Sciences at Virginia Tech, undoubtedly shared much of what he presents in his book with countless students over the years. The Gyroscope of Life reads like part memoir and part last lecture, and is the work of someone who has an obvious passion for science and nature.

Parrish spends the first few chapters of his book writing mostly about his life and how he came to be a biologist. He acknowledges his privelege – “born male, white, and American in an era where each of those attributes provided me major advantages” –  having essentially been placed on third base from the start, “well down the third base line.” An aspiring zoologist turned botanist, he spent his early years in graduate school studying seeds and seed dormancy. It’s a topic that obviously interests him, as several pages of the book are spent considering what’s going on inside of a seed. “Seeds provide the widest-spread examples of suspended life,”  Parrish says. Are they alive or dead or neither?

Two additional, major life events play a prominent role in the arc of Parrish’s book. One being his break from organized religion and the other his battle with advanced prostate cancer. He grew up in an orthodox Christian home with a very literal understanding of the Bible. His education put him at odds with what he was taught growing up about (among other things) the age of the earth and its creation. Eventually he came to understand that science and religion “exist in separate non-overlapping spheres – the physical and the metaphysical.” He doesn’t necessarily see science and religion as being inherently at odds with each other, but his understanding of science makes it difficult to “find resonance in religion” due to the “cacophony of dissonance” it offers.

In addressing his prostate cancer, Parrish underwent an operation that gave him a newfound perspective on gender. Freed from “testosterone poisoning,” he was able to more fully consider sex and gender from a biological perspective, which he says he had been doing for decades prior to the operation. He spends a good portion of the book “demystifying sex and gender.” One compelling example he offers involves avocado flowers, which actually change gender over time, a phenomenon known as synchronous dichogamy.

avocado flowers (Persea americana) via wikimedia commons

Over the course of its pages, The Gyroscope of Life covers a significant number of topics in the fields of biology and ecology. It’s a relatively short book, but as it careens through such wide-ranging material, it does so in an approachable and suprisingly succint manner. Parrish’s sense of humor, which doesn’t waver despite how bleak the discussion sometimes gets, helps carry the story along and keeps things interesting. Parrish covers evolution (“[Biologists] argue that, if evolution didn’t happen, it should.”), taxonomy (“the name for naming things”) and sytematics, ecological niches (“[humans] are essentially living niche-free and ecosystemless”), domestication, and so much more. The last chapter is spent discussing agroecosystems (“the organisms and abiotic environment that interact in a human-managed agricultural setting”), a topic he spent much of his career studying.

The underlying message of this book, as I see it, is a simultaneous celebration for life on earth and a concern for the direction things are going considering how humans have managed things. Parrish has some admonition for humans in light of how we’ve treated our home planet, but he isn’t too heavy-handed about it. Overall, reading the book felt like sitting in on a lecture given by a friendly and dynamic professor who has obviously given a lot of thought to what he has to say.

Check out the following video to see David Parrish describe the book in his own words.

More Book Reviews on Awkward Botany:

The Hidden Flowers of Viola

Violas keep a secret hidden below their foliage. Sometimes they even bury it shallowly in the soil near their roots. I suppose it’s not a secret really, just something out of sight. There isn’t a reason to show it off, after all. Showy flowers are showy for the sole purpose of attracting pollinators. If pollinators are unnecessary, there is no reason for showy flowers, or to even show your flowers at all. That’s the story behind the cleistogamous flowers of violas. They are a secret only because unless you know to look for them, you would have no idea they were there at all.

Cleistogamy means closed marriage, and it describes a self-pollinating flower whose petals remain sealed shut. The opposite of cleistogamy is chasmogamy (open marriage). Most of the flowers we are familiar with are chasmogamous. They open and expose their sex parts in order to allow for cross-pollination (self-pollination can also occur in such flowers). Violas have chasmogamous flowers too. They are the familiar five-petaled flowers raised up on slender stalks above the green foliage. Cross-pollination occurs in these flowers, and seed-bearing fruits are the result. Perhaps as a way to ensure reproduction, violas also produce cleistogamous flowers, buried below their leaves.

an illustration of the cleistogamous flower of Viola sylvatica opened to reveal its sex parts — via wikimedia commons

Flowers are expensive things to make, especially when the goal is to attract pollinators. Colorful petals, nectar, nutritious pollen, and other features that help advertise to potential pollinators all require significant resources. All this effort is worth it when it results in the ample production of viable seeds, but what if it doesn’t? Having a method for self-pollination ensures that reproduction will proceed in the absence of pollinators or in the event that floral visitors don’t get the job done. A downside, of course, is that a seed produced via self-pollination is essentially a clone of the parent plant. There will be no mixing of genes with other individuals. This isn’t necessarily bad, at least in the short term, but it has its downsides. A good strategy is a mixture of both cross- and self-pollination – a strategy that violas employ.

The cleistogamous flowers of violas generally appear in the summer or fall, after the chasmogamous flowers have done their thing. The fruits they form split open when mature and deposit their seeds directly below the parent plant. Some are also carried away by ants and dispersed to new locations. Seeds produced in these hidden flowers are generally superior and more abundant compared to those produced by their showy counterparts. People who find violas to be a troublesome lawn weed – expanding far and wide to the exclusion of turfgrass – have these hidden flowers to blame.

That being said, there is a defense for violas. In the book The Living Landscape by Rick Darke and Doug Tallamy, Tallamy writes: “Plants such as the common blue violet (Viola sororia), long dismissed by gardeners as a weed, can be reconstituted as desirable components of the herbaceous layer when their ecosystem functionality is re-evaluated. Violets are the sole larval food source for fritillary butterflies. Eliminating violets eliminates fritillaries, but finding ways to incorporate violets in garden design supports fritillaries.”

sweet violet (Viola odorata)

In my search for the cleistogamous flowers of viola, I dug up a sweet violet (Viola odorata). I was too late to catch it in bloom, but the product of its flowers – round, purple, fuzzy fruits – were revealed as I uprooted the plant. Some of the fruits were already opening, exposing shiny, light brown seeds with prominent, white elaiosomes, there to tempt ants into aiding in their dispersal. I may have missed getting to see what John Eastman calls “violet’s most important flowers,” but the product of these flowers was certainly worth the effort.

Fruits formed from the cleistogamous flowers of sweet violet (Viola odorata)

Up close and personal with the fruit of a cleistogamous flower

The seeds (elaiosomes included) produced by the cleistogamous flower of sweet violet (Viola odorata)

See Also:

Podcast Review: Plants and Pipettes

Gardening was my first introduction to plants. I enjoyed growing plants so much that I decided to study them. Or rather, I studied the growing of them, i.e. horticulture. During my studies, I became increasingly interested in botany, a vast scientific field that investigates all things plant related, from their evolutionary history to their cellular biology to their interactions with other organisms, etc. Now I am obsessed with pretty much anything to do with botany. However, the molecular side of plant science has never been much of a pursuit of mine. Until now.

What has piqued my interest in this isn’t a university course or a dense textbook on the subject, but instead a podcast hosted by two molecular biologists – Tegan and Joram – who make learning about molecular plant science considerably more interesting than I had previously found it to be. Their podcast (and blog of the same name) is called Plants and Pipettes, and they have been consistently publishing both written and audio content on their site for well over a year now.

The bulk of the Plants and Pipettes podcast consists of Tegan and Joram summing up and discussing a recent plant science research article. While I occasionally get lost in the discussion (particularly when the research delves deep into molecular biology), they both do an exceptional job explaining the science and offering insights that I would not get if I attempted to read the papers on my own. When listening to this portion of the podcast, it helps to have a basic understanding of molecular biology, but it isn’t entirely necessary as the hosts often review basic concepts while discussing the research.

Over the course of the podcast’s history, additional segments have been added. These rarely have anything to do with molecular biology, so if you don’t see yourself tuning in for the research discussion, definitely tune in for the rest. One segment is called My Favorite Plant in which one of the hosts talks about a plant they are interested in that week. Next is Diversity in Plant Science, in which they pick a person that is not a white male and talk about their life and contributions to science (George Washington Carver, for example). After that they define and discuss a cognitive bias, and then they share random things (sometimes science-y, sometimes not) that they find fun or interesting or important to share. Each episode typically ends with a cat fact, as they both have a profound love for cats (although everything is a cat to Joram, apparently).

grass triggerplant (Stylidium graminifolium) was Joram’s favorite plant in episode 12 of Plants and Pipettes (image credit: wikimedia commons)

A highlight among the early episodes was an interview they did with a researcher at the University of Minnesota who is working with pennycress (Thlaspi arvense). This plant is a common weed, but it shows potential for being a productive and useful oilseed crop, similar to a few of its relatives in the mustard family. Speaking of weeds, a fun fact in episode 29 caught my interest, in which Tegan shares an example of Vavilovian mimicry involving rice and barnyard grass (Echinochloa crus-galli). A great introduction to their ongoing series about cognitive biases is episode 37 in which they discuss the Texas sharpshooter fallacy. And of course, I have to recommend listening to episode 48, in which Tegan gives a shout out to Awkward Botany and my new zine Dispersal Stories. How cool is that!?

pennycress (Thlaspi arvense) discussed in episode 8 of Plants and Pipettes (image credit: wikimedia commons)

While I am not always able to keep up with the discussions about molecular plant biology, I still really love listening to this podcast. Apart from the interesting content, the hosts are the real appeal.  Not only do I appreciate their social justice rants and their support for open science, but I also find their sense of humor and lack of pretension refreshing. They are excellent models of the way that science communication should be done. 

If you check out Plants and Pipettes and decide you need more Tegan and Joram in your life, check out a new podcast they just started with Ellen from Plant Crimes podcast called Plant Book Club, in which they choose a plant-themed book to read and discuss. You can also watch/listen to Tegan and Joram talking about their podcast on Career Conversations

More Podcast Reviews on Awkward Botany:

Tea Time: Violet Leaf Tea

The genus Viola is large and widespread. Its flowers are easily recognizable and obviously popular. A significant number of Viola species, hybrids, and cultivars are commercially available and commonly planted in flower beds and container gardens. Certain species have even become weeds – vicious lawn invaders in some people’s opinion. Violets (or pansies in some cases) are also edible. Their leaves and/or flowers can be used in salads, drinks, and desserts. One way to use the leaves is to make tea, so that’s what I did.

I imagine you can make tea from any Viola species, but after some searching I found that two species frequently mentioned are Viola odorata and Viola sororia – two very similar looking plants, one from the Old World and the other from the New World.

sweet violet (Viola odorata)

Viola odorata – commonly known as sweet violet, wood violet, or English violet – is distributed across Europe and into Asia and has been widely introduced outside of its natural range. It has round, oval, or heart-shaped leaves with toothed margins that grow from the base of the plant, giving it a groundcover-type habit. Its flowers range from dark purple to white and are borne atop a single stem that curves downward at the top like a shepherd’s crook. It has no leafy, upright stems, and it spreads horizontally via stolons and rhizomes. The flowers are distinctly fragrant and have a long history of being used in perfumes.

One way to get a good whiff of these flowers is to try a trick described in the book The Reason for Flowers by Stephen Buchmann:

Go into a garden or any natural area and select one or more flowers you want to investigate…. Select a small, thoroughly washed and dried glass jar with a tight-fitting lid. Place just one type of flower in the jar. Set your jar in a warm, sunny place such as a windowsill and come back in an hour or two. Carefully open the lid and sniff…. If you’ve selected a blossom with even the faintest scent, you should be able to smell it now, since the fragrance molecules have concentrated inside the jar.

sweet violet flowers inside glass jar

Viola sororia – native to eastern North America –  is also commonly planted outside of its native range. It’s clearly a favorite, having earned the distinction of state flower in four U.S. states. Known as the common blue violet (or myriad other commons names), it looks and acts a lot like sweet violet. I distinguish them by their flowers, which are wider and rounder (chunkier, perhaps) than sweet violet flowers, and their leaves, which are generally more heart-shaped. Feel free to correct me. If, like me, you’re having trouble identifying violets, keep in mind that Viola species are highly variable and notorious hybridizers, so don’t beat yourself up over it. It’s their fault, not yours.

common blue violet (Viola sororia)

Violets bloom when the air is cool and the days are short. They are among the earliest plants to flower after the new year and among the latest plants flowering as the year comes to a close. In his entry on violets in The Book of Forest and Thicket, John Eastman refers to these early bloomers as “this low, blue flame in the woods.” They are like “a pilot light that ignites the entire burst of resurrection we call spring.” I can’t really picture spring without them. I find their unique flowers so intriguing that I fixate on them whenever I see them. And once I learned that I could make a tea out of their leaves, I had to try it.

I used the leaves of Viola odorata (or what I, with my amateur skills, identified as V. odorata). I picked several of what looked to be young leaves and left them to dry in the sun for several days. Later, I chopped them up and brewed a tea according to the instructions found on this website, which suggests using one tablespoon of dried leaves in sixteen ounces of water. Apparently, a little goes a long way, and I probably could have used fewer leaves than I did.

dried, chopped up leaves of sweet violet (Viola odorata) for making tea

The tea has a nice green color and smells a bit like grass to me. It may even taste like grass. I found it fairly bitter. Sierra didn’t like it and called it musty. I enjoyed it, but would likely enjoy it more if I hadn’t made it quite so strong. The aforementioned website also recommends combining violet leaf with other things like mint, dandelion, clover, and/or chamomile. I imagine a combination of ingredients could be better than just violet leaf on its own. Another site warns that “some of the wild violets have an unpleasant soapy flavor,” so that’s something to keep in mind when selecting your leaves for tea and other things. Either way, violet leaf tea is an experience worth having.

See Also: Pine Needle Teas

Introducing Weeds of Boise

Weeds are the wild flora of our cities. Their occurrence and continued existence is not directly reliant on humans in the same way that the plants in our yards, parks, gardens, and other green spaces are. They may take advantage of the disturbance that we cause when we stir up the soil or cease maintenance in a particular spot, and they certainly appreciate the runoff from our sprinklers and the free rides their seeds get on our pets and ourselves, but they don’t need us looking after them to survive. They get by on their own whether we approve of them or not. Most may not be native to the area, but their presence is natural – undirected and involuntary – and for this reason I consider them to be a valid component of our urban flora.

If you visit a natural area outside of our cities, you are likely to find a field guide associated with that region that will help you identify many of the plants found there. However, such a field guide is not likely to exist for the plants found in a vacant lot or an urban roadside near you. Sure, there are plenty of general weed identification guides, some of which may be specific to where you live, but they are often focused on agricultural/horticultural weeds or weeds found in natural areas outside of the built environment. Few show weeds in an unmaintained urban setting the way that Peter Del Tredici’s book or Maggie Herskovits’ zine do. Clearly we need more resources that identify and document our urban floras.

Weeds of Boise is an attempt to begin that process for my corner of the world. After coming across websites like The Weedalouge (cataloging the wild plants of Philadelphia), Weeds of Melbourne (“a visual glossary of the weedy heritage of Melbourne, Australia”), and Spontaneous Urban Plants (an attempt to map weeds in urban areas around globe), I decided to start the process here in Boise, Idaho. My goal is to select locations across the city and inventory the weeds found there at different times of the year. I will keep a running list of what I find and photograph as many plants as I can. I will make a separate blog post for each location and maintain a link for each post in the Weeds of Boise page. The blog posts will be updated as I collect more data for each site. Over time I hope to have a more clear picture of what weeds are found here and how they are distributed.

Because many of these plants are cosmopolitan, the weeds found in my area are likely similar to the ones found in yours, but there may be some unique differences. If more projects like this are undertaken, we will have a better idea of the similarities and differences among our urban floras. Upon closer observation, we are likely to make some interesting discoveries. Who knows what we might find once we really start looking at these obnoxiously ubiquitous but otherwise completely ignored plants?

Weeds of Boise is also a reminder that you can botanize anytime anywhere. You don’t have to jet off to some remote location to see plants. It’s likely that there are wild plants growing right outside your front door – each one with a unique name and story and just as worth getting to know as any other.

2019: Year in Review

It’s the start of a new decade and the beginning of another year of Awkward Botany. As we’ve done in years prior, it’s time to look back at what we’ve been up to this past year and look forward to what’s coming in the year ahead. Thank you for sticking with us as we head into our eighth year exploring and celebrating the world of plants.

The most exciting news of 2019 (as far as Awkward Botany is concerned) is the release of the first issue of our new zine, Dispersal Stories. It’s a compilation of (updated) writing that originally appeared on Awkward Botany about seeds and seed dispersal and is the start of what I hope will be a larger project exploring the ways in which plants get around. Look forward to the second issue coming to a mailbox near you sometime in 2020.

Also new to our Etsy Shop is a sticker reminding us to always be botanizing, including while riding a bike. Stay safe out there, but also take a look at all the plants while you’re cruising around on your bike or some other human-powered, wheeled vehicle. Whether you’re in a natural area or out on the streets in an urban or rural setting, there are nearly always plants around worth getting to know.

This year we also started a Ko-fi page, which gives readers another avenue to follow us and support what we do. Check us out there if Ko-fi is your thing.

Buy Me a Coffee at ko-fi.com

We also still have our donorbox page for those who would like to support us monetarily. As always you can stay in touch with us by liking and following our various social media accounts (Facebook, Twitter, Tumblr, and our currently inactive, but that could change at any moment Instagram). Sharing is caring, so please be sure to tell your friends about Awkward Botany in whatever way you choose. We are always thrilled when you do.

Below are 2019 posts that are part of new and ongoing series. You can access all other posts via the Archives widget. 2019 saw a significant drop in guest posts, so if you’d like to submit a post for consideration, please visit our Contact page and let me know what you’d like to write about. Guest writers don’t receive much in return but my praise and adulation, but if that sounds like reward enough to you, then writing something for Awkward Botany might just be your thing. And while we’re on the topic of guest posts, check out this post I wrote recently for Wisconsin Fast Plants.

Happy Reading and Plant Hunting in 2020!

Inside of a Seed & Seed Oddities:

Podcast Review:

Poisonous Plants:

Tiny Plants:

Eating Weeds:

Using Weeds:

Drought Tolerant Plants:

Tea Time:

Field Trip:

Awkward Botanical Sketches:

Guest Posts:

Pine Cones and the Fibonacci Sequence

While we’re on the topic of pine cones, have you ever considered their scales and the spirals they form? Nature is replete with spirals, so perhaps it’s no surprise that they are found in pine cones. The more interesting thing is that the number of spirals found on pine cones are almost always Fibonacci numbers. But maybe that’s not that surprising either, as Fibonacci numbers are also pretty common in nature.

Add 1 plus 1 and you get 2. Add 2 plus 1 and you get 3. 3 + 2 = 5, 5 + 3 = 8, and 8 + 5 = 13. One, two, three, five, eight, and thirteen are Fibonacci numbers. Continue adding the sum to the number that came before it, and that’s the Fibonacci Sequence. The ratio of two neighboring Fibonacci numbers is an approximation of the golden ratio (e.g. 8/5 = 1.6). This is commonly represented by drawing a series of squares on graph paper and then drawing a spiral across the squares. Each square drawn is larger than the last in accordance with the Fibonacci sequence, and the spiral drawn through the squares is a logarithmic spiral.

So, what does this have to do with pine cones? Well if you count the number of spirals that are going to the right, then count the number of spirals going to the left, you usually end up with two adjacent numbers in the Fibonacci sequence. Most often it’s either 5 and 8 or 8 and 13. You can find this same pattern in lots of other plant parts, including the aggregate fruits of pineapples, the disc flowers of sunflowers (and other plants in the aster family), the bracts of artichoke flowers, florets on a cauliflower, and leaf arrangements of all sorts of other plants.

The arrangement of leaves is called phyllotaxis, and when the leaves on a stem form a spiral pattern it’s called a phyllotactic spiral. The benefit the plant receives from having its leaves grow in a spiral formation down the length of its stem is actually quite simple – it keeps them from shading each other out and thereby maximizes their exposure to the sun. If you measure the angle between each leaf, the angle should be the same between each adjacent leaf on the stem. In order for the number of spirals to be a Fibonacci number, the leaves have to be oriented at a specific angle from each other. But this isn’t always the case. Depending on the angle, the number of spirals could be part of some other number sequence, like Lucas numbers perhaps.

While the specifics of plant growth can be quite complex, the reason for the patterns that result is actually quite simple. As plants grow new parts, they are put in a spot where there is room for them to grow, which is at some angle from the part that grew before it. Once that angle is “chosen,” it generally doesn’t change, and as more plant parts grow, a spiral forms (or no spiral forms at all, depending on the pattern of growth). If plant parts are oriented at a specific angle (~ 137.5o), the numbers of spirals end up being Fibonacci numbers. For a more thorough and entertaining explanation of all this, check out this three part video series from Khan Academy. It’s well worth the watch.

And now an example:

Count the number of right-hand spirals on this ponderosa pine cone. There are 8. That’s a Fibonacci number!

Count the number of left-hand spirals on this ponderosa pine cone. To make it easier to count, you can start or end with the top left spiral that has alternating red and green scales. There are 13. That’s another Fibonacci number!

And now your mission, should you choose to accept, is to find a pine cone (or some other conifer cone) in which the number of right and left-hand spirals are not Fibonacci numbers. They’re definitely out there, so let me know what you find in the comment section below.

Further Reading:

Out Now! Dispersal Stories #1

Before I started this blog, I had spent 16 years publishing zines at a steady clip and sending them to all corners of the world through the mail. I had never really meant to abandon zines altogether, and in some ways, putting all my writing efforts into a blog felt a little like a betrayal. My intention had always been to one day put together another zine. Now, six and a half years later, I’m happy to report that day has come.

Rather than bring an old zine back from the grave, I decided to make a new zine. Thus, Dispersal Stories #1. It’s quite a bit different from zines I’ve made in the past, which were generally more personal and, I guess, ranty. In fact, Dispersal Stories is very much like this blog, largely because it is mostly made up of writing that originally appeared here, but also because its main focus (for now) is plants. What sets it apart is that, unlike this blog, it zeroes in on a specific aspect of plants. As the title suggests, it’s all about dispersal. For much of their life, plants are essentially sessile. Once they are rooted in place, they rarely go anywhere else. But as seeds, spores, or some other sort of propagule they are actually able to move around quite a bit. The world is their oyster. What’s happening during this period of their lives is the focus of Dispersal Stories.

But why do a zine about this? Apart from just wanting to do another zine after all these years, my hope is that Dispersal Stories will be the start of a much more ambitious project. A book perhaps. My interest in dispersal was born out of my interest in weeds, and there is so much that I would like to learn and share about both of these subjects – so much so that the blog just doesn’t really cut it. So, I’m expanding the Awkward Botany empire. First a zine, then a book, then … who knows? I’m an oyster! (Or something like that.)

Dispersal Stories #1 is available in our etsy shop, or you can contact me here and we can work something out. While you’re at it, check out our new sticker.

If you love looking at plants and learning their names, then you probably enjoy doing it any chance you get. Usually it’s an activity you do while walking, but who says you can’t botanize while riding a bike? This sticker is inspired by a friend who once said that while mountain biking you get to “see three times as many flowers in half the time!” Stick it on your bike or in some other prominent location to remind yourself and others that we can botanize anytime anywhere.

Your purchase of one or both of these items helps support what we do. You can also support us by buying us a ko-fi or putting money in our donorbox. Sharing these posts also helps us out. If you get a copy of the zine, let us know what you think by sending us an email, a message on twitter or facebook, or by leaving a comment below. As always, thanks for reading.

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