Category Archives: Botany

Pursuing mystery: how we found out lichen has a third partner and is saving the earth

Mixed lichen and moss on a stick Mount Tamalpais, California by Betsey-CrawfordFor 150 years lichen has been known to be a combination of two life forms. The outside is a fungal matrix, rather like the crust of a baguette,  which gives structure and protection to the softer, more filamentous inside, formed by one of the algae family, or occasionally a cyanobacteria. These latter two provide nutrients for themselves and the protective fungus via photosynthesis. The word symbiosis (Greek for ‘living with’) was coined in 1868 specifically to describe lichen’s interrelationships. When I wrote my first post about lichen two years ago, this is where our knowledge stood. A few months later, that changed. A hidden partner had been found, and the story of that discovery is wonderful. 

As is appropriate to its subject, the entire project was a symbiosis. Montana lichenologist Toby Spribille was inspired by an essay by British Columbia lichenologist Trevor Goward. Trailing like long strands of hair from the branches of Pacific Northwest trees are two lichens formed by exactly the same fungus and alga. But they are different colors. Tortured horsehair lichen (Bryoria tortuosa) is greenish yellow, a result of the production of toxic vulpinic acid. Edible horsehair lichen (Bryoria fremontii), also called wila, is dark brown, does not produce a toxin, and was an important food for indigenous northwest peoples. They were thought to be different until genetic testing came along, so we need to include the genome pioneers in the team.

Edible horsehair lichen, or wila (Bryoria fremontii) Peyto Lake, Banff, Alberta. Photo by Jason Hollinger via Creative Commons

Edible horsehair lichen, or wila (Bryoria fremontii) Peyto Lake, Banff, Alberta. Photo by Jason Hollinger via Creative Commons

Growing up in Montana, Spribille had always been fascinated by the forests of hanging lichen. But he may well never have been in a position to explore them. Despite his yearning to study science, he was home-schooled in a family that didn’t believe in it, so he couldn’t do so until he left home. Then he was faced with the hurdles of finding a university he could afford that would accept him without a formal high school degree. He heard that European schools are more open to people like him. Since his family spoke the language, he went to Germany, where the University of Gottingen took him in.

After getting his Ph.D. at the University of Graz in Austria, Spribille showed up at the McCutcheon Lab at the University of Montana, which specializes in symbiosis. ‘I study lichens,’ he said, and was warmly welcomed by John McCutcheon, who urged him to study genomics, as well. Genetic analysis was crucial to his discovery since scientists have spent many years probing lichens under powerful microscopes without seeing the hidden partner. Inspired by Goward’s query, he began poking around in the Bryoria genome to see what caused the two seemingly identical lichens to be different.

A lichen called tree lungwort (Lobaria pulmonaria) Tongas National Forest, Alaska by Betsey Crawford

Tree lungwort (Lobaria pulmonaria) Tongas National Forest, Alaska

Even with genetics on his side, and the McCutcheon team to brainstorm with, Spribille couldn’t find anything new until he decided to expand his search. The fungi long associated with lichen are from the Ascomycota family, and he looked for their genes first. Then he decided to look more broadly at the whole fungal kingdom and discovered genes from the Basidiomycota family, home of the types of mushrooms we’re used to eating. Excited but doubtful, the team wondered if they’d stumbled on a passing impurity or an infection. It wasn’t until he took the basidiomycetes data out of his calculations that he saw that the production of vulpinic acid went, too. That, he says, was the eureka moment.

Actually seeing the fungus cells involved high tech genetic tagging with fluorescent colors to visually separate the alga and the two fungi. It also involved — my favorite detail — a very low tech trip to the grocery store to buy laundry detergent. The basidiomycetes were under a crust of polysaccharides on the surface of the lichen, and Spribille used the soap to dissolve the coating. That enabled him to tag the newly found yeast cells with their own color and to see that they surround the lichen, embedded in the outer cortex. The yellow Bryoria tortuosa had lots more of the yeast than the edible brown fremontii, which is what enables the former to produce vulpinic acid. 

Old man's beard lichen (Dolichnousnea longissima) Tongass National Forest, Alaska by Betsey Crawford

Old man’s beard lichen (Dolichnousnea longissima) Tongass National Forest, Alaska

Soon after he hit his eureka moment, scientists all over the world got involved, and it was quickly found, now that they knew what to look for, that varieties of the newly discovered Cyphobasidium yeasts showed up in 52 other genera on six continents. As with the Bryoria, their presence helps explain differences in appearance in genetically similar lichen. The team expands, the search continues, and the lichen world is forever changed. 

I’ve planned for a while to update my lichen post. What got me thinking about it now is my fascination with the origins of Project Drawdown, which I wrote about in my last post. It started with Paul Hawken asking a question no one else was asking. In his case, it was ‘what are we already doing that can actually reverse global warming?’ It seems like such an obvious thing to ask, and yet brilliant scientists and policymakers weren’t doing so. Like Isaac Newton wondering why the apples in his orchard fell downward and not sideways, many seemingly simple questions, asked by people who then proceed to pursue the mystery, revolutionize our knowledge and perceptions. 

Snow lichen (Flavocentria nivalis) with alpine bearberry (Arctostaphylos alpina), mountain harebell (Campanula lasiocarpa) and other alpine plants make up the tundra of the Yukon. Photo by Betsey Crawford

White snow lichen (Flavocentria nivalis) with alpine bearberry (Arctostaphylos alpina), mountain harebell (Campanula lasiocarpa) and other alpine plants make up the tundra of the Yukon. Note the light and dark lichen on the rock.

Surprises in the lichen world are rare enough that the story made headlines. The more attention, the better, since lichens are crucial to the health of our planet. We know this because another team pursued a question no one had asked. Climate researchers have long studied the amount of carbon held in oceans and forests. But it wasn’t until 2012 that scientists at the Max Planck Institute for Chemistry in Germany wondered about the carbon impact of cryptograms, which are photosynthesizers that don’t flower, like mosses, algae, and lichen. 

Together these tiny life forms cover 30% of the earth’s plant-bearing soil surfaces. Lichen alone covers 8% of the planet, which closes in on 16 million square miles. The team found that cryptograms sequester about 14 billion tons of carbon dioxide each year. That’s 12.7 gigatons, which is the measurement used in Drawdown. The number one solution there is estimated to make a difference of 89.74 gigatons between now and 2050. Using simple multiplication (though I suspect it’s more complicated than that) lichen and its cohorts could sequester over 400 gigatons by then.

Dramatic lichen on toxic serpentine rock doing the incredibly slow work of creating dirt. Mount Burdell, Novato, California. Photo by Betsey Crawford

Dramatic lichen on toxic serpentine rock doing the incredibly slow work of creating dirt. Mount Burdell, Novato, California

The carbon cycle is the most widely studied and reported aspect of global warming. Also crucial is the nitrogen cycle, which, now wildly out of balance, is producing another dangerous greenhouse gas, nitrous oxide. There, too, the cryptograms shine, by taking close to 50 million tons of nitrogen from the air and putting it into the soil each year, where it’s a crucial nutrient. This is part of another important role they play: breaking down rock and creating and stabilizing soil in barren landscapes. 

Given all it provides for the stability of the earth’s fragile atmosphere, it’s ironic, and tragic, that global warming is itself the biggest threat to lichen’s existence. Though most of us rarely think about these life forms, we depend on them. But that shouldn’t surprise us. The slow wisdom of evolution put lichen in place 400 million years ago. DNA analysis shows us that the newly discovered yeasts joined forces with the original partners 100 million years ago. The cyanobacteria that sometimes takes the place of algae in the mix has been here for 2.5 billion years. They were the first photosynthesizers on the planet, creating the oxygen-rich world everything has depended on since.

The fairy cups of the lichen species Cladonia, Denali National Park, Alaska by Betsey Crawford

The fairy cups of the lichen species Cladonia, Denali National Park, Alaska

The first human fossils are a mere 2.8 million years old. Our possibility lay in the same possibility of all the beings we share the planet with: cycles of oxygen, carbon, nitrogen, water, soil building, plate tectonics and temperature regulation. These forces create and maintain the thin crust and surrounding atmosphere that provide our delicate envelope of life. Lichen’s carbon and nitrogen regulating abilities aren’t evolutionary accidents. They are traits carefully evolved to provide a living, breathing world for themselves and each subsequently evolving being. 

In a culture where embracing interconnections within our own species is a huge challenge, it may be hard to fathom how deeply our existence is interwoven with a being that is itself created by an interweaving of beings. All of earth’s forms, including ourselves, are both presence and possibility on our paths through existence. The whole planet is a symbiont, a network of intimately and intricately related parts, each evolving detail generating deepening possibilities for the whole.

Lichen and other cryptograms are dominant in the tundra of northern Canada and Alaska. All the white on the ground in this picture from the Tombstone Mountains in Yukon is a leafy lichen. Photo by Betsey Crawford

Lichen and other cryptograms are dominant in the tundra of northern Canada and Alaska. Here snow lichen (Flavocentria nivalis) lives up to its name in Tombstone Territorial Park in Yukon.

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Songlines 2017: widening circles

A wild rose, Rosa woodsii, in Coeur d'Alene, Idaho by Betsey Crawford

I live my life in widening circles
that reach out across the world

These words, from Rainer Maria Rilke’s exquisite Book of Hours, are slightly paradoxical because this year we traveled less than any of the other years since we set off on our journey in 2011.  My partner George’s health isn’t up to life on the road at this point, so my songlines this year became widening circles around Greenbrae, California, just north of San Francisco, where there is a whole world to explore. California hosts one of the most diverse native plant populations in the country and is home to snow-capped mountains, oceans, deserts, grasslands, coastal forests. Earlier this year I celebrated this extraordinary mix within easy reach in Wild Abandon: the Mystery and Glory of Plant Diversity. 

Fairy slipper orchid (Calypso bulbosa) on Mount Tamalpais, Mill Valley, California by Betsey Crawford

Fairy slipper orchid (Calypso bulbosa)

Californians also care deeply about saving wild places. Half of the state is preserved land, an extraordinary accomplishment. I marvel at the knowledge of native plants and birds I find when meeting lawyers, nurses, teachers, business people on walks and hikes. In May, I joined a bioblitz for the first time. In fact, it was the first time I’d ever heard the word. I wrote about the fun we had cataloging every living thing within a small area of Mount Tamalpais in Blessed Unrest: the Bioblitz. It’s a celebration not only of our day but of the millions of people around the world who are taking actions, large and small, to save and repair the world.

White-lined sphinx moth (Hyles lineata) Gary Giacomini Open Space Preserve, Woodacre, California by Betsey Crawford

White-lined sphinx moth (Hylea lineata) 

Rilke’s quote comes from one of the highlights of the year: spending three days with the ecological and Buddhist philosopher, Joanna Macy. Her Work that Reconnects helps people to confront their grief at what is happening to the earth, and to renew their commitment to the work they feel called to do. Rilke’s genius has supported her ever since she discovered him when she lived in Germany in her twenties, and her translation of his poetry punctuated our time with her. In The Work that Reconnects: a Weekend with Joanna Macy, I wrote about the extraordinary, moving circle of twenty-eight people, young and old, who gathered to move through Joanna’s spiral of gratitude, grief, and renewal. I found it uplifting, joyous, complicated, loving, inspiring, painful: life distilled into a weekend

California poppy (Eschscholzia californica) El Soprante, California by Betsey Crawford

California poppy (Eschscholzia californica) 

Out of the time with Joanna came other circles. There were several landscape designers there, and one of them, Susan Friedman, had a number of native plant gardens on a tour in early May. So, off I went. I described what I found in Retaining Paradise: Gardening with Native Plants, and wrote about a longtime passion: using our gardens to recreate the bird and animal habitat that built-up neighborhoods inevitably destroy. 

Tall thistle (Cirsium altissimo) and bee, Golden Prairie, Golden City, Missouri by Betsey CrawfordJoanna’s workshop was held at Canticle Farm, an urban farm in the heart of Oakland. While we were there, the bees from the beehive swarmed, as they got ready to leave for a new home. This inspired Susan, who’d been thinking about having a hive, to find a class on beekeeping. It had never occurred to me to do such a thing, but when she asked if I was interested, I instantly wrote back, ‘of course.’ I loved our day with the bees, and chronicled it in Treasuring Bees, Saving the World

Rock tunnel along the road in southern Utah by Betsey CrawfordOur life on earth is tied to the health and life of the bees, which can also be said of many things, including dirt. In The Intimate Bond: Humans and Dirt, I treasure its multi-faceted community and innate intelligence, which made it possible for us to evolve and keeps every living thing on earth going. Dirt is not cheap! Much of the urgent need to take care of the thin layer of soil on our planet lies in the endless time frame it takes to form it. Focusing on Utah, where you can literally drive through the planet’s ancient past, I explored its mysteries and consolations in The Solace of Deep TimeBlack crowned night heron in Corte Madera Marsh, Corte Madera, California by Betsey CrawfordIn Greenbrae, I live near a lagoon that attracts a wonderful, shifting community of shorebirds all year. Around Easter an avalanche of ducklings started, family after family of adorableness so acute I was addicted to that walk for three months. This handsome night heron is part of  A Season of Birds, where I describe my happy visits to the vibrant life there — which included an unusual extended family — and honor the necessity and hard work of preserving and reclaiming such lands. 

Pacific coast iris (Iris douglasiana) along the Hoo-Koo-e-Koo Trail, Larkspur, California by Betsey Crawford

Pacific coast iris (Iris douglasiana) 

And, of course, I spent the year celebrating flowers. For a few weeks each spring, California is an iris addict’s paradise. I wrote about my feelings for these bewitching flowers in Elegant, Wild, Mysterious: Loving Iris, and suggested that flowers’ ability to inspire love may help save the planet. I discussed the complications of our gorgeous roses in Passion and Poison: the Thorn in the Rose. In early August I explored one of the most joyful flower families on earth in One Big Happy Family: the Asteraceae, and created a gallery to show their beauty and wide diversity
Canada goldenrod (Solidago canadensis) Westport, New York by Betsey Crawford
Then, later in August, on a trip to New York, I was able to do something I can’t do in California: stand in a sea of goldenrod. Naturally, that called for celebrating the way this extraordinary explosion of luminous yellow connects us to the heart of nature in The Gold Rush: the Joyful Power of Goldenrod. I also visited an early childhood home, set in a magical green world. I wove my memories and my realization about how deeply that time affected the life I’ve lived into A Girl in the Garden of Eden.

For Halloween I thought choosing ghostly white flowers for Happy Halloween: Ghosts in the Landscape would be fun, and it was. To my surprise, the fun turned out to be exploring why we have white flowers at all, and how their chemistry is related to ours. That post, too, inspired a gallery: Luminous Whites.

Bush anemone (Carpenteria californica) white flowered native plants, San Ramon, California by Betsey Crawford

Bush anemone (Carpenteria californica)

The only essay I didn’t write was written by Pope Francis. Laudate Si Repictured is an interweaving of words from his eloquent encyclical on the care of the earth with pictures of our beautiful planet. One of the quotes encapsulates the message I kept finding on my circling songlines this year:

All of us are linked by unseen bonds and together form a kind of universal family, a sublime communion which fills us with a sacred, affectionate and humble respect.

Human and seagull footprints in the dirt in Kenai, AlaskaLoving the place we find ourselves will give us the strength and vitality to preserve it. Damage to the world and its people will be slowed and salvaged by love: for the earth, for our fellow creatures, for its waters and air, for the dirt under our feet, for the wondrously intricate web of all beings of which we are a part.  A profound understanding of our inherence in the natural world– the idea that we are the planet, not on the planet — is a gift we give both the earth and ourselves. 

I wish you all a new year of love, commitment, and beauty.

Celebrating Laudate si: clouds reflected in Dease Lake, British Columbia

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The gold rush: the joyful power of goldenrod

Canada goldenrod (Solidago canadensis) and Joy Pye weed (Euchotrichum maculate) Westport, New York by Betsey CrawfordOne of the blessings of a visit to New York late last summer was seeing something I miss in California: a world awash in goldenrod. A member of the vast and happy Asteraceae family, Solidago canadensis, one of a hundred species of native goldenrods in the US, overflowed fields and banked roadsides near my sister’s house in the Adirondacks. Filled with tiny yellow daisy-like flowers up close, looking like an explosion of yellow fireworks from a near distance, and like a sea of sparkling yellow foam from a greater distance, goldenrod is the late August and September wildflower in most of the country, along with its aster companions.

In her passionately wise and luminous book, Braiding Sweetgrass, botanist Robin Wall Kimmerer tells the story of her first interview with her advisor at the State University of New York’s School of Environmental Science and Forestry. Why, he asked, did she want to study botany. She had her answer ready: she wanted to know why goldenrod and asters look so beautiful together. His answer was crushing. That, he said, was not a valid reason to study botany. Such considerations belonged to art, not science. 

Canada goldenrod (Solidago canadensis) Westport, New York by Betsey Crawford

Canada goldenrod (Solidago canadensis) Westport, New York

Luckily for us, she was, though daunted, not discouraged, and later found other, more sympathetic teachers and mentors. But for a while, she left the indigenous knowing of her heritage behind while studying science as it was presented in her courses. It wasn’t until she was studying for her Ph.D. in Wisconsin that she found herself at a gathering of native elders who could speak of the depths of plants in ways her botany classes had not: their relationships to other plants, to the places where they grew, to the animals, birds and humans in their midst. The stories of their origins and names. The wisdom they have to share. 

And their beauty. As an artist, I would have happily explained (as artist friends did) that yellow and purple look so beautiful together because they are complementary colors. Each primary color, in this case yellow, has a complement composed of the other two primaries, here red and blue, creating purple. Complementary colors have a powerful synergy, both making the other zing, creating a combination more electric than, for example, pink and purple. However lovely the latter combination, it will always be less exciting to our brains than pairing purple and yellow, or orange and blue, or red and green. These are not the combinations you’d think of for a meditation garden. But if you want to look at a field of scintillating color, or add excitement to your garden, your painting or your wardrobe, interweaving complements is a surefire way to do it.

Pasture thistle (Cirsium discolor) and Canada goldenrod (Solidago canadensis) Curtis Prairie, Madison, Wisconsin by Betsey Crawford

Pasture thistle (Cirsium discolor) and Canada goldenrod (Solidago canadensis) Curtis Prairie, Madison, Wisconsin

Other than red flowers against green leaves, nature hasn’t gone out of her way to combine complementary colors. And red flowers are relatively rare, orange even rarer, and true blue almost nonexistent. Purple is fairly common, and yellow abundant. All are dwarfed by the numbers of white flowers, which offer no opportunity for complementary drama. So it’s especially striking when nature has not only combined complements but thrown them about with as much abandon as she has goldenrod and asters. Robin Wall Kimmerer was talking specifically about New England asters, with their deep purple petals and deeper-than-goldenrod yellow centers. The stronger the purple, the more scintillating the combination, though with the many lighter asters, and with the pink-purple thistle shown here, the combination is still electric. 

New England asters (Symphyotrichum novae angliae) courtesy of the Ohio Department of Natural Resources

New England asters (Symphyotrichum novae angliae) courtesy of the Ohio Department of Natural Resources

But I agree with her about goldenrod and New England asters: their combined gorgeousness is a perfectly good reason to want to study botany. And while it may be true that aesthetics are not the province of science, there’s fascinating science connected to beauty, starting with the exquisitely sensitive cones nestled in our retinas. Millions of neurons, waiting to encode for our brains the light waves bouncing off the world around us. Two-thirds of our cones are dedicated to the longer wavelengths of the warmer colors — like the yellows of goldenrod. Another third is devoted to the seeing their green leaves. Only 2% of our cones are reading the purple aster petals, which reflect back the shortest wavelengths of light. 

Late purple aster (Symphyotrichum patens) and Canada goldenrod (Solidago canadensis) along the road in northern New York by Betsey Crawford

Late purple aster (Symphyotrichum patens) and Canada goldenrod (Solidago canadensis) along the road in northern New York

Why yellow and purple? Carotenoids in the goldenrod and aster centers, and anthocyanins in the aster petals. Chemicals that reflect those colors back to us, and, among other things, protect the flowers from too much of the ultraviolet light we can’t see, and that burns both our skin and the petals’. To bees, who can see in the ultraviolet spectrum,  goldenrod’s yellow is even more incandescent than it is to us. But they hardly need the pizazz. There are so many solidagos, with so many individual flowers per plant, in so many places that they can’t be missed. Bees abound in those fields, picking up the sticky, heavy pollen and bringing it back to the hive to make bee bread for the winter.

I think it’s the sheer exuberance of the solidago phenomenon that I love so much. This is nature at her most joyful, maybe even her whackiest. Why not throw millions of luminous yellow flowers out there as most other flowers fade? Throw in some purple for dazzle! Turn the neighboring leaves vivid red and orange! Provide winter food for thousands of tiny creatures who return the favor by pollinating the flowers. Create larger creatures to stand in the fields, with carefully crafted eyes connected to brains capable of awe. Fill them with wonder at what has been wrought. Those wildly yellow early autumn fields are a sign of a creation that can’t be stopped. 

Canada goldenrod (Solidago canadensis) Westport, New York by Betsey Crawford

Canada goldenrod (Solidago canadensis) Westport, New York

I take a lot of comfort in this vast energy. Although such fields are plowed and bulldozed daily for grazing or agriculture, houses or parking lots, this sheer vibrancy tells me nature is far from fragile in the face of her heedless humans. Another essay in Braiding Sweetgrass details the destruction of Lake Onondaga, sacred to the Onondaga people of upstate New York. After more than a century of pumping industrial waste up to sixty feet deep into and around the lake, along with the sewage of the growing city of Syracuse, it’s now a Superfund site. In fact, nine Superfund sites. Long gone are the wetlands, the trees, the oxygen-generating plants, the moss, the birds, the frogs, the once crystal clear water.

The same story can be told of countless places. The details vary, the heartbreak is painfully similar. There is a lot of restoration going on, even if grudgingly on the part of the corporations and governments that caused the destruction. People the world over are pulling beloved, damaged places back from the brink. The same is happening with Lake Onondaga. There are attempts, some good, some bad, to restore a semblance of natural life to this dead landscape. Of the ones described in the essay, my favorite is the work being done by nature herself, who sent the ‘oldest and most effective of land healers…the plants themselves.’

Seeds of trees took root in the white, gluey sludge and slowly grew. Birds landed in their branches and dropped the seeds of berrying shrubs. Clovers and other legumes, among the most important of our plant allies, arrived and began pulling nitrogen into the muck. The endlessly adaptable grass family moved in. Their roots add humus, and the first glimmering of soil making can be seen. 

It’s a slow process of enormous strength, and one we can trust. That’s where I take comfort. Of course, we should be doing everything in our power to stop the destruction and repair the damage. Nature should be able to rely on us, too. But as she asks, she also inspires.  When we need courage, and ardor, and zeal for this work, she invites us to stoke those fires by standing in the midst of a sea of goldenrod as it pulses with energy, radiating her vibrant, enduring, indomitable heart. 

Canada goldenrod (Solidago canadensis) Westport, New York by Betsey Crawford

Canada goldenrod (Solidago canadensis) Westport, New York

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Happy Halloween: ghosts in the landscape

Cotton grass (Eriophorum angustifolium) Single delight (Moneses uniflora) Wynn Nature Center, Homer, Alaska by Betsey Crawford

Cotton grass (Eriophorum angustifolium) Single delight (Moneses uniflora) Wynn Nature Center, Homer, Alaska

When I first thought of the title for this Halloween post, I had fun in mind — white flowers that have ghostly or skeletal effects — and there are those, like the cotton grass above and the trillium and others below. But the more I thought about white flowers, the more questions I had. How did they become white? Is it a loss of pigment or a color of its own? Why are there so many of them? Depending on the region, they can far outnumber flowers in the blue to red to orange range, and outstrip the numerous species of yellow flowers. Studies show that pollinators, given a choice, will gravitate to colors. So what’s the evolutionary advantage of white? Is there one? It turns out that white flowers are full of mystery. Which is, indeed, fun.

White flowers: Pacific trillium (Trillium ovatum) Blithedale Canyon, California by Betsey Crawford

The very ghostly newborn petals of Pacific trillium (Trillium ovatum) Blithedale Canyon, California

The earliest angiosperms, more than 100 million years ago, are thought to have been white, cream or pale green. Since Darwin, people — including me — have been happily saying that the more vivid colors slowly evolved to attract pollinators, whose vision long predated the flowers. And that appears to be true. Or, at least, there’s no strong body of evidence saying it’s not true. But, as it turns out, there’s no strong body of empirical evidence saying it is true. Empirical evidence implies that we can see something happen in real time, and it’s hard to see an evolutionary process in our brief lifespan. 

White flowers: Ghost flower (Mohavea confertiflora) Anza Borrego Desert, California by Betsey Crawford

This one is actually called ghost flower (Mohavea confertiflora) Anza Borrego Desert, California

There are studies that show, for example, flowers becoming redder in as little as a single generation as more hummingbirds pollinate them. Further studies show that when given choices, pollinators will choose colors over white flowers, though that may be because the colorful ones stand out more vividly against green foliage. Finding flowers efficiently is crucial to the success of both flower and pollinator, so the easier the flower is to see, the better. Very important, the stronger the relationship a pollinator has with a specific color, the more likely it is to bring matching pollen from one flower to fertilize another in the same species.

White flowers: Sitka burnet (Sanguisorba stipulata) Wynn Nature Center, Homer, Alaska by Betsey Crawford

Sitka burnet (Sanguisorba stipulata) Wynn Nature Center, Homer, Alaska

So, we know that pollinators have an intimate relationship with flower color. Or, more accurately, with the color’s wavelength, since the purple we see is not what the pollinator sees. But, with the explosion of genetic information in recent years, there’s also a growing appreciation for other factors that are at play, especially in how white flowers have evolved. Flowers in the blue to purple to red range use anthocyanins to create their color, the chemicals that make foods like grapes and raspberries so good for us. If the dominant anthocyanin is delphinidin, the flower is purple, if pelargonidin, red, if cyanidin, magenta to lavender. Other flavonoids, such as anthoxanthins, along with a variety of carotenoids, create yellows and oranges. 

White flowers: Single delight (Moneses uniflora) Wynn Nature Center, Homer, Alaska by Betsey Crawford

Single delight (Moneses uniflora) Wynn Nature Center, Homer, Alaska

In the course of mutations that alter the expression of specific enzyme and protein pathways, the amounts of these color-inducing chemicals can vary, changing the color of the flower. Mutations may also cause the pathways to stop working altogether. The resulting loss of function can return the flower to its primordial white, a state that’s likely to be irreversible since it would take a series of very specific mutations for those particular pathways to work again. 

White flowers: Sand lily (Mentzelia nuda) Smoky Valley Ranch, Oakley, Kansas by Betsey Crawford

Sand lily (Mentzelia nuda) Smoky Valley Ranch, Oakley, Kansas

There is a widely accepted division of flower/pollinator relationships: bees prefer flowers in the blue range, while hummingbirds gravitate to red, butterflies to pink, moths and beetles to white. And studies do back up these general preferences. But there’s a lot of variation. If bees weren’t interested in pollinating white flowers, we wouldn’t have almonds, apples, plums or any number of other fruits in the Rosaceae family. Thus, other factors are apparently important, among them scent, availability, abundance, learned behavior, competition, as well as the match of plant shapes to pollinator characteristics. It also may be that the subtle pinks that make white apple blossoms so poignantly beautiful to us are neon signs to bees. More mysteries. As every study says, ‘more research is needed.’

White flowers: Fried egg plant (Romneya trichocalyx) San Ramon, California by Betsey Crawford

Fried egg plant (Romneya trichocalyx) San Ramon, California

As fascinating as I find all this, I’m somewhat resistant to the idea that the gorgeous hues of reds, purples and lavenders I love so much are a result of ‘the number of hydroxyl groups attached to the B-ring of the molecule,’ or that tender, luminous whites are due to the functional failure of these groups. Reducing something as magical as color to the action or loss of enzyme and protein pathways seems like a comedown. On the other hand, my seeing and treasuring these colors is possible only because my body relies on similar pathways. Which brings another mysterious dimension forward: the fact that flowers and I share biological functions and genes, and, in sharing them, share each other.

White flowers: white thistle (Cirsium hookerianum) Waterton National Park, Alberta by Betsey Crawford

White thistle (Cirsium hookerianum) Waterton National Park, Alberta

Not only that, but without a strong connection to a variety of pollinating animals and insects, and the biology and genetics we have in common with them, neither flowers nor I would be here to begin with. All those pathways need constant nourishment. Like me, the pollinators depend on flowers for nutrition and survival. Flowers depend on these friendly forces, which can include me, for reproduction. We all depend on a huge array of microbes and fungi to create the nutrients we thrive on from the soil at our feet. We depend on the movements of air currents, the hydrology of water, the minerals released from rocks. 

Sitting among flowers on a forest path, or the desert floor, or out in a meadow, we’re held in a vast array of interlinking pathways, beating our hearts, feeding our cells; moving water, air, nutrients; creating color, vision, scent. All mysteriously designed to keep every one of us — flower, leaf, dirt, human, bee, bird, beetle — alive and blossoming. 

White flowers: White paintbrush (Castilleja occidentalis) Waterton National Park, Alberta by Betsey Crawford

White paintbrush (Castilleja occidentalis) Waterton National Park, Alberta

More beautiful white flowers can be found in the gallery Luminous Whites.

I’d love to have you on the journey! If you add your email address, I’ll send you notices of new adventures.

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One big, happy family: the Asteraceae

A sunflower (Helianthus annuus), a memeber of the Asteracea family, In Cape Breton, Nova Scotia, Canada by Betsey CrawfordI took the picture above six years ago this month, standing in a field of sunflowers on Cape Breton Island on the east coast of Canada. It was the first place we went when we started the journey that has taken us to so many wonderful places. I’ve never forgotten the joy of standing in that field, completely surrounded by the happiest of flowers, growing with wild abandon toward the August sun.

With almost 24,00o species, the Asteraceae family is vast and exuberant. It’s literally everywhere you go, except Antarctica. The accompanying photos range from Alaska to the Anza Borrego Desert in southern California. They reflect one of the family’s strengths: the ability to thrive in many different environments, whether hot or cold, dry grassland or wet marsh, in alpine meadows or among desert cactus. Some are important commercially: sunflower, safflower and canola oils. Camomile and echinacea tea. Artichokes, lettuce, tarragon, radicchio, endive. One shrub even produces a form of latex. The horticultural market depends on many of them.

Mule ears (Wyethia anguvstifolia) taken along Chimney Rock trail in Point Reyes National Seashore, California by Betsey Crawford

Mule ears (Wyethia anguvstifolia) Point Reyes National Seashore, California

The most familiar asteraceae configuration is the sunflower and its relatives: a central circle of disk florets, surrounded by a crown of ray florets that look like and act like petals, attracting insects to pollinate themselves as well as the less showy disk flowers. The family name comes from these composite forms: aster derives from the Latin word for star. But there are a variety of other structures. Some, like the thistle and the arnica below, are discoid, with disk but no ray flowers. Others, like the dandelion, are ligulate, with no disk flowers and ‘petals’ of strappy ligules. 

Rayless arnica (Arnica disoidea) Blithedale Canyon, Larkspur, California by Betsey Crawford

Rayless arnica (Arnica disoidea) Blithedale Canyon, Larkspur, California

As a group, they tend to develop a fluffy seed head, a pappus of filaments that originally surround the base of the ovary, and grow longer as the flower goes to seed. With their feathery attachments, seeds are easily dispersed by wind, which helps account for the ubiquity of yarrow, fleabanes, dandelions, asters and other family members. Some seeds have hooks on them and spread out by attaching themselves to animal fur or clothing. 

Siberian aster (Aster sibericus) Denali National Park, Alaska by Betsey Crawford

Siberian aster (Aster sibericus) Denali National Park, Alaska

What looks like an individual flower is an inflorescence, a bowl-, vase- or cone-shaped capitulum, holding its lovely arrangement of hundreds of ray and disk florets. The capitulum is held by green bracts, or phyllaries, sometimes many layers of them, constituting an involucre. When you eat the bud of an artichoke flower, you peel off, dip in melted butter, and then eat one phyllary after another, until you get to the heart, which is the capitulum containing the disk flowers. The phyllaries can be plain or beautifully sculptural. Their differences, in number, shape and position, are often a key to identifying close species. 

Analysis of fossil pollen found in Antarctica dates the Asteraceae to 80 million years ago, when the continent was still part of Gondwana, before it floated south to the icy pole. Species were lost during the K-T extinction, which killed the dinosaurs around 66 million years ago. But those that survived thrived and multiplied during the great flowering of the warm Late Paleocene and Early Eocene epochs, as did every other plant family. The asteraceae in turn benefitted their pollinating insects, and were especially important to the evolution of bee species.

Tall purple fleabane (Erigeron peregrinus) with two butterflies Waterton Lakes National Park, Alberta, Canada by Betsey Crawford

Tall purple fleabane (Erigeron peregrinus) and friends, Waterton Lakes National Park, Alberta, Canada

They are a pollinator’s dream: one landing, up to 1,000 flowers. The sunflower, our biggest and most dramatic North American native asteraceae, dedicates a most intriguing and charming trait to bees and other pollinators. It starts with buds and young flower heads, still covered with their green, photosynthesizing bracts, following the sun over the course of the day. At night, they work their way back toward sunrise, moving faster near the solstice, and more slowly as the nights grow longer.

 

Brittlebush (Encelia farinosa) Anza Borrego Desert, California by Betsey Crawford

Brittlebush (Encelia farinosa) Anza Borrego Desert, California

This cirdadian heliotropism is driven by growth hormones that spur growth on the east side of the stem during the day, lengthening that side, and tilting the flower head toward the west. At night, another hormone spurs growth on the west side, moving the flower to face east by morning. In experiments that interfere with this sun tracking, plants quickly lose mass and leaf surface, cutting down on photosynthesis and thus vitality and size.

Their sungazing stops at maturity. The ‘clock genes’ turn off, leaving entire fields of sunflower heads facing east. That way they are warmed early in the day, making them five times more likely to be visited by pollinators than experimental plants arranged to face west.  And there are lots of pollinators: bees, butterflies, moths, flies, wasps, wind, and, in South America, birds. With their warm, open faces offering almost unlimited opportunity for fertilizing, reproduction becomes very efficient, which explains the diversity and worldwide habitat of the family.

Pasture thistle (Cirsium discolor) in a late summer sea of goldenrod (Solidago canadensis) Curtis Prairie, Madison, Wisconsin by Betsey Crawford

Pasture thistle (Cirsium discolor) in a late summer sea of goldenrod (Solidago canadensis) Curtis Prairie, Madison, Wisconsin

Standing in a field of sunflowers, or prairies of thistles, coneflowers and goldenrods,  I am not only surrounded by the sheer exuberance of vividly colored, beautifully shaped flowers, with their attendant bees and butterflies. I am surrounded by a long history of carefully ‘chosen’ evolutionary changes that remain mysterious despite all the genetic information we can now gather about plants. Why so many yellows? And why pink, or white? Why feathery leaves on one family member, big chunky leaves on another? Why is this one so tiny, and this one gigantic? Why a cone on one, a bowl on another? This heavenly exuberance of form and color is a delightful mystery.

Prairie coneflower (Rudbeckia nitida) Konza Prairie Preserve, Manhattan, Kansas by Betsey Crawford

Prairie coneflower (Rudbeckia nitida) Konza Prairie Preserve, Manhattan, Kansas

In that sunlit field I’m also surrounded by a form of life — the flowering angiosperms with their nutritious fruits — that may well be responsible for me, a member of a much later species, being able to stand there at all. That nourishment helped my forebears to develop the eyes and consciousness to celebrate the wonder around me. That may even be the point of evolving me at all: a way for the universe to contemplate its glories.

Prairie blazing star (Liatris pycnostachya) Curtis Prairie, Madison, Wisconsin by Betsey Crawford

Prairie blazing star (Liatris pycnostachya) Curtis Prairie, Madison, Wisconsin

Relishing the sunny warmth of a summer day, drinking in the beauty and vitality of the flowers around me, grateful for our shared history and destiny — these are moments of transcendence that make life rich and fulfilling. Our beautiful world makes them so available, but we too often rush by. Even when we stop, we feel we must quickly return to the practical tasks that make life possible. But our world is always there, waiting to be treasured. Waiting for the eyes and ears it has gifted us with to turn toward these great and beautiful mysteries. “Life is this simple,’ theologian Thomas Merton wrote. “We are living in a world that is absolutely transparent and the divine is shining through all the time.”

Blanket flower (Gaillardia aristata) in Coeur d'Alene, Idaho by Betsey Crawford

Blanket flower (Gaillardia aristata) in Coeur d’Alene, Idaho

More pictures of this exuberant family can be found in the Asteraceae Gallery.

I’d love to have you on the journey! If you add your email address, I’ll send you notices of new adventures.

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It takes a village: the community of lichen

hypogymnia-species-alectoria-samentosa-witchs-hair-lichen-lobaria-pulmonaria-lungwort-Fish-Creek-Hyder-Alaska-by-Betsey-CrawfordThe farther I went north last summer, the more I found a world full of lichen. It’s everywhere in Alaska, and a dominant species in the arctic tundra. But it’s everywhere else, too, covering 8% of the world’s surface. Lichen holds the desert in place, fills the forests, hangs off branches in cool, damp coastal woods as well as in warm swamps. It’s on the trees in your backyard, slowly covering your grandparents’ tombstones, growing on fence posts, spreading under your feet as you climb mountains.

lobaria-pulmonaria-lungwort-cladonia-species-moss-Kenai-Wildlife-Refuge-Kenai-Alaska-by-Betsey-Crawford

Large lungwort (Lobaria pulmonaria) ‘leaves’ live with a species of Cladonia among the moss and ferns on a tree in the Kenai National Wildlife Refuge in Alaska

Lichen is indeed a village: it’s composed of varying forms of fungi, algae, and cyanobacteria living in symbiosis. Strands of fungi weave together to provide housing, which protects the algae and bacteria from environmental challenges like desiccation and UV radiation. The algae and bacteria provide food via sugars formed through photosynthesis. The resulting body, or thallus, lives on its substrate — wood, soil, rock, occasionally air — along with other members of the community, usually moss, often other forms of fungi and algae, and the trees, ferns, flowers, rocks, and animals of whatever environment it’s growing in.

cladonia-stygia-black-footed-reinderr-lichen-flavocentria-nivalis-snow-lichen-Denali-National-Park-Alaska-by-Betsey-Crawford

Black-footed reindeer lichen (Cladonia stygia) mixed with snow lichen (Flavocentria nivalis) in the Yukon tundra

Though I am no lichenologist — identifying the few lichens here that I’ve been able to name was a study in cross-eyed bewilderment — I’ve always been fascinated by them. I went to Denali National Park one day to hike, but, on finding a world covered with lichen, got down on the ground and spent the afternoon with them, in all their variety: tiny, lacy shrubs of one lichen run through with little branchlets of another, next to a large patch of dark brown sheets of felt lichen. A white crustose lichen so completely covered the flange of a tree stump that it wasn’t until I put my hand on it that I realized I was looking at wood, not granite. That white crust was dotted with a pink one. Tiny spires, holding up minute cups, occasionally edged in vivid red, grew all over the rest of the stump, happily embedded in moss.

cladonia-digitata-flavocentria-nivalis-snow-lichen-Denali-National-Park-Alaska-by-Betsey-Crawford

A Cladonia species around a tuft of snow lichen (Flavocentrai nivalis)

This plucky, endlessly adaptable, weirdly beautiful, not-plant, not-animal feeds reindeer and caribou. It holds and releases moisture, helpful to the plants that grow with it. It has some medicinal uses, and shows up in Japanese and Korean cuisines. Some are used as dyes, and some in making perfume. But its most important ecological contributions are its ability to take nitrogen from the air and add that essential element to the soil; its ability to live in, stabilize, and form soil in barren landscapes; and its ability to sequester carbon. Lichen, with the mosses and algae they grow among, all tiny and indomitable, take up as much carbon yearly as is released by the burning of forests worldwide. This amounts to 14 billion tons of carbon, as opposed to the 2.2 billion (and falling) tons absorbed by the Amazon rainforest.

moss-lichen-tree-stump-Kenai-Wildlife-Refuge-Kenai-Alaska-by-Betsey-Crawford

A tree stump with an entire village of moss and lichen in the Kenai Wildlife Refuge, Alaska

As hardy and amazingly adaptable as lichens are in their natural habitats, they are threatened by several things, especially air pollution, deforestation, and global warming. The first limits healthy growth, the second habitat, and the third will begin to further limit habitat, as lichens sensitive to temperature will have to go to higher and higher altitudes to survive. Those that cannot will die out.

And here is where the larger questions come in. If you ask people whether they would prefer to drive cars to work or save lichens, most people would ask, “What’s lichen?” It wouldn’t be an issue at all. It would seem obvious that we’re more important than a bunch of fungus and algae mashed together and ruining our wooden fence. We’re letting species go extinct every day. Why would a few little lichen matter?

icmadophila-ericetorum-fairy-barf-lichen-Denali-National-Park-Alaska-by-Betsey-Crawford

Tiny pink splotches of the interestingly named fairy barf lichen (Icmadophila ericetorum) in Denali National Park, Alaska

We don’t know why lichen matter. That’s the problem with every extinction. We see the stakes through human eyes. We want to get from place to place in our cars, we love computers, we need homes that are warm in winter and cool in summer. My home is tiny footprint, but I drove it to Alaska and back last year. Would I give up such incredible experiences to preserve the right environment for lichen? A challenging question!

peltigera-praetextata-felt-lichen-cladonia-species-Denali-National-Park-Alaska-by-Betsey-Crawford

Brown felt lichen (Peltigera praetextata) with a Cladonia species in Denali National Park, Alaska

We are part of the biome, and we need habitat. There is an infinity of things we can do to reduce our effect on the planet, but even if we do every one of them, humans will still have an outsized footprint. Species will be edged out. Others will hang on, threatened.

We know some of these extinctions will matter. If bees die out, we face a world without fruit, flowers, nuts. If lichen dies out we’ll first lose their ability to sequester carbon, which will be released into an atmosphere already threatened by rising carbon dioxide levels. So temperatures may rise further, endangering more and more species.

biological-crust-Butler-Wash-Bluff-Utah-by-Betsey-Crawford

A section of the desert’s biological crust, in Butler Wash near Bluff, Utah

We would also lose a crucial soil producer and stabilizer. It’s hard for us to see, in the brown crusts of the sandy desert, how important a role those tiny, combined elements play in securing nutrients, water, and footing for roots. Hard to imagine the time span taken to break down rock into soil. To us, dirt has always been here, but we’re newcomers on the planet, perhaps even passers-by. The ramifications of such losses spread out like waves. Whatever we do to allow lichen to go extinct might well mean we’ve created a world inhospitable to us.

lichen-on-stone-Butler-Wash-Bluff-Utah-by-Betsey-Crawford

Lichen on stone in Butler Wash, near Bluff, Utah

These questions are important, but they are also human-centered, asking of everything how it helps us. Cyanobacteria are 2.5 billion years old, the first photosynthesizers on earth, producers of the oxygen-rich atmosphere that all subsequent biodiversity depends on. The earliest lichen fossils  are 400 million years old.  The earliest human fossil is 2.8 million years old. The forces that created the earth with infinite slowness ticked lichen off the formation list much earlier than humans. Perhaps we’re here to help lichen.

Every form in nature is part of a whole, a web woven together with meticulous evolutionary care. We can only pull so many of those threads out before the fabric begins to weaken. And there may be some combination of threads which, when pulled, will destroy the integrity of the whole. The problem is, we don’t know which ones, leaving us with the great challenge of caring for the entire village on our finite globe.

cladonia-rangiferina-reindeer-lichen-Stony-Hill-Amagansett-New-York-by-Betsey-Crawford

Reindeer moss (Cladonia rangiferina) along a trail in Stony Hill, Amagansett, New York

I’d love to have you on the journey! If you add your email address, I’ll send you notices of new adventures.

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Grizzly bear in Denali National Park, Alaska by Betsey Crawford

Songlines 2015: north to Alaska