Tag Archives: thistle

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

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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.

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Treasuring bees, saving the world

Bees love tall thistle (Cirsium altissimo) shown with a bee, Golden Prairie, Golden City, Missouri by Betsey Crawford

Tall thistle (Cirsium altissimum) Golden Prairie, Golden City, Missouri

The invitation came from Susan Friedman, whom I met on the weekend with Joanna Macy, and whose native plant gardens were part of Retaining Paradise. The Work that Reconnects workshop was held at Canticle Farm, an urban farm in Oakland, a more or less rectangular open space created by combining the yards and gardens behind a collection of houses. During the weekend the bees swarmed, meaning that the queen, responding to pressures in the hive, led a large number of her subjects out to form a new one. For an afternoon, thousands of bees hung in a mass on a sturdy tree branch, while scouts went looking for new sites. In the meantime, a beekeeper on someone’s speed dial was called to put the swarm into a new hive box and take it to another farm. 

This extraordinary event led Susan, already thinking about having a hive on her property, to find a class on beekeeping. Though it had never occurred to me to do such a thing, when she asked me if I was interested I immediately wrote back, ‘Of course.’ So there we were, on a hot June Saturday, in a demonstration garden a couple of blocks from San Francisco’s City Hall. Our teacher, Mark, was an utterly engaging bee geek, who punctuated his opening talk with continual delight at the intricate, fascinating life of the bees he is clearly passionate about. 

Bees love prickly poppy (Argemone polyanthemos) Konza Prairie Biological Station, Flint Hills, Kansas by Betsey Crawford

Prickly poppy (Argemone polyanthemos) Konza Prairie Biological Station, Flint Hills, Kansas

Though I had no expectations about my fellow students beforehand, I was surprised at how young everyone else was, starting with Mark. We were a small group, but still, the idea that there are six young, urban professionals interested in spending a golden summer day learning about keeping bees was very heartening. Because keeping bees is, in it’s broadest sense, keeping the world. 

Bees were here with the dinosaurs. The relationship between bees and flowers is 130 million years old. Starting in the paleolithic era, cave drawings all over the world include scenes of figures climbing ladders to get honey, buzzed by a swarm of bees. People have written about their fascination with bees and the joys of honey ever since the alphabet was invented. But they may not survive the world we have created. And we may not survive without them. 

Bees love camas (Camassia quamash) Tubbs Hill, Coeur d'Alene, Idaho by Betsey Crawford

Camas (Camassia quamash) Tubbs Hill, Coeur d’Alene, Idaho

Mark took us through the basics of hive life: the development of the queen and her prodigious task of laying up to 2000 eggs a day. The myriad, unceasing tasks of the female workers who do all the work of the hive. They tend the queen, feed the young, forage for and store nectar and pollen, make honey, create wax, clean house, vibrate their wing muscles to regulate temperature. All lives are brief: queens can live for five years, though are considered productive for three. Workers live about a month and a half. The far fewer male drones, whose only job in life is to fertilize queens from other hives, die in this task or by being ejected from the hive at the end of the summer. So, to keep the hive going, new life needs to be constantly fostered.

Their work ethic is prodigious. One pound of honey means that 10,000 bees have flown 75,000 miles in short segments, visiting up to 8 million flowers. A good forager will have brought back a total of 1/4 teaspoon of nectar in the course of her life. She’ll also bring water, and pollen collected on her bristly hairs or in pouches on her legs. As she flies from flower to flower in search of nectar, she leaves some of her pollen load on the next flower she visits, and picks up more, performing the crucial task of pollination as she goes.

Beehive frame with honey, covered by beeswax, in the upper right. In the lower right are cups with white larva, and capped cups that house the pupae. You can see the glint of light on the cups holding nectar, on its way to becoming honey. The larger cups at the bottom right are for drones. Photo by Betsey Crawford

Bees on a beehive frame with honey, covered by beeswax, in the upper right. In the lower leftt are cups with white larva, and capped cups that house the pupae, from which will emerge adult bees. At the top center, you can see the glint of light on the cups holding nectar, on its way to becoming honey. The larger cups along the left hand frame are for drones.

The highlight of the class was donning bee suits and opening the hives. Bee boxes with portable wooden frames of comb long ago replaced the round, impenetrable beehives that meant bees had to be killed to harvest honey. We pulled out the hanging frames and watched the bees at work. Mark suggested dipping the end of a twig in the honey and holding it to the bees’ heads. The tiniest imaginable red tongues zipped out to lick it off. He showed us the queen, which he had marked with a green dot.

All this time the bees were very calm. We were well covered, though I was soon unconcernedly pulling my gloves on and off to take pictures. But after a while the bees began to buzz and fly more dramatically, the result of getting too warm on that hot day, and anxious about the well-being of their tribe. So we closed the boxes again.

Bees love wild geranium (Geranium erianthum) Wynn Nature Center, Homer, Alaska by Betsey Crawford

Wild geranium (Geranium erianthum) Wynn Nature Center, Homer, Alaska

Our class was not about native bees. Beekeeping is devoted to the imported European honey bee, Apis mellifera, whose communal lifestyle and behavior make it a mobile pollinating force for agriculture, and a prolific source of honey. But all bee populations are excellent pollinators, some native ones far more so than the honey bee. All are losing ground dramatically. In the last 120 years, we’ve lost half of our native bee species. There is no one cause, and the problem, though far more acute now, was first noted in 1860. 

Even then, loss of habitat to growing urbanization and industrialization, along with widespread clearing for agriculture, were among the culprits. Since World War II, intensive farming has done away with the old hedgerows between fields, full of varieties of wildflowers and brambles. Vast fields of wind-pollinated grains have no flowers for bees to forage. Vegetable farmers largely harvest crops like lettuce and radishes before they flower and go to seed. That leaves fruit and nut trees, and vegetables that develop from the ovaries of flowers, like squash.

Bees love western wood lily (Lilium philadelphicum) Waterton Lakes National Park, Alberta, Canada by Betsey Crawford

Western wood lily (Lilium philadelphicum) Waterton Lakes National Park, Alberta, Canada

But even in places where such crops are abundant, as in the Central Valley of California, bees are rapidly losing ground. When they don’t kill the bees directly, pesticides, especially the neonicotinoids introduced in the 1990s, damage their nervous systems, impairing their ability to navigate and forage, thus weakening the whole hive. Any loss of vitality leaves bees prey to mites and fungi that can devastate the colony.

Monoculture is another issue. The almond groves in the Central Valley bloom for three weeks. Before and after, if there are no native hedgerows, and no flowering ground covers, there’s nothing to keep the mostly non-colony-forming native bees in place. The honey beekeepers load their hives onto trucks and move them to the next crop, a potentially stressful lifestyle that may also be impacting those bees.

Bees love red monkey flower (Mimulus lewisii) Waterton Lakes National Park, Alberta, Canada by Betsey Crawford

Red monkey flower (Mimulus lewisii) Waterton Lakes National Park, Alberta, Canada

What would life without bees be like? From a human perspective, we would lose most flowers, most fruits, vegetables, nuts, coffee, tea. Our diet would consist largely of grains and meat from animals that eat those grains. Without clover and alfalfa, the dairy industry would falter, and beef prices would skyrocket. We would have lettuce for salad while the seed supply lasts, but no cucumbers or tomatoes, and no oil or vinegar. No jam or jelly, no strawberry shortcake in June, no pumpkin pie at Thanksgiving. No lemonade or orange juice. Our most nutritious vegetables — like broccoli, carrots, onions, kale — would be gone.

Cotton clothing would disappear. Our gardens would be green. No more fields of wildflowers. The 20% of flowers pollinated by butterflies, beetles, and hummingbirds would still exist, but butterflies are also disappearing. All ecosystems would eventually diminish as bee-pollinated plants died off in alpine meadows, grasslands, forests, wetlands, deserts. The ability of these systems to regenerate soil, filter water and clean the air would be impaired, endangering more and more plants. Eventually, all living things could be under threat.

Bees love smooth aster (Aster laevis) taken at a rest stop planted with native plants in Wisconsin by Betsey Crawford

Smooth aster (Aster laevis) at a rest stop planted with native plants in Wisconsin

Thus the loss of bees is far more than a human problem. Because of the threat to agriculture, farmers and scientists the world over have been working to figure out why we’re losing bees and what to do about it. But though the solutions are challenging, and the sudden collapse of colonies devastating, it isn’t hard to figure out why bees are struggling. We’ve produced a planet that is inhospitable to them. And, as I wrote when contemplating the loss of lichen to climate change, a world that’s inhospitable to our fellow inhabitants may soon be inhospitable to us. 

Instead of trying to harness the bee to our needs, we would do better catering to theirs. If we create a world where they can flourish, chances are far better that we will, too. Among the answers: organic farming and gardening. Bee friendly hedgerows dividing farm fields and native flowering groundcovers among crops. Regenerative agriculture. Sustainable development. Preservation and restoration of habitat. Gardening with natives — the plants native bees evolved with — like the bee-loved flowers accompanying this post. This is the quilting together of restored habitat I wrote about in Retaining Paradise

Bees love strawberry hedgehog cactus (Echinocereus fendleri) Cross Canyon, southwest Colorado by Betsey Crawford

Strawberry hedgehog cactus (Echinocereus fendleri) Cross Canyon, southwest Colorado. There is a bee dedicated to pollinating cactus flowers.

In the end, it all depends on how we think about these things. We can choose to look at the world from a bee’s point of view, or a forest’s, or a river’s. Or from the perspective of an intact ecosystem. By and large, our culture and economy don’t support this way of seeing. We contemplate a meadow that took 4.5 billion years to evolve and see it as a potential shopping mall. We see driveways and houses and swimming pools. As understandable as this view might be, given our culture, and to some extent our needs, it’s destroying the world we depend on.

Without bees, flowers may never have evolved. Without flowers, and their nutritious fruits, we may never have evolved. We share over a third of our genes with bees. Our connections with our fellow beings, as with the planet we all arose from, are profound. What if instead of seeing bees as merely useful, or fascinating, or in the way, we could see them as kin? With such a shift in vision, gardening, farming, and habitat restoration become ways to foster the vitality of our cousins as well as ourselves. We become a vast extended family — flowers, fruits, bees, soil, water, humans — weaving the fabric of life together.

Bees love blue wild iris (Iris missouriensis) taken in Monticello, Utah by Betsey Crawford

Wild iris (Iris missouriensis) in Monticello, Utah

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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