What is it about cactus flowers? I’ve always been a big fan, because, well, who wouldn’t be? But lately I’ve been beguiled by them. Or, maybe, obsessed.
On the way to Santa Fe with husband and dog, we wandered along the Rio Grande on a side road near the tiny town of Pilar. This is our typical method of travel – “let’s see where that goes,” one of us says, and so we do. The river rolled by at the road’s edge, full and glossy with spring runoff. River runners in blue rubber boats floated by and we soon came to a campground and a bend in the river where more boats were being put in, with all the usual noisy activity.
The road took a sharp turn here and proceeded uphill. Amid the scrub and the cheat grass and rugged boulders of basalt we struck gold. There were Prickly Pears in lavish bloom. I’m sure I caught “Prickly Pear fever” there and then.
Prickly Pears are immediately recognizable, of course, for their green oval (technically ovate) pads armed with white spines and clusters of darker bristles. The pads are stems, not leaves. This is where the plants store water. Prickly Pears and related Cactaceae are “stem succulents,” as opposed to “leaf succulents,” like Stonecrop.
The pads don’t just store water, they also do the job of leaves and take care of photosynthesis, the process by which the plant turns sunlight (plus carbon dioxide and water) into food. Prickly Pears do have leaves but they’ve been modified by evolution into those “prickly” spines that ward off the casual grazer.
Prickly Pears are members of the Opuntia genus. The genus name derives from the name of a city (Opus) in Ancient Greece. It’s a “large genus,” according to Nelson (1), and the main species she identifies is Opuntia polyacantha, which she also calls “Hunger Cactus.” Polyacantha means “many-spined”.(2)
Nelson says colors are “yellow fading to orange.” Guennel, on the other hand, says it’s red or yellow. (3) Colors, of course, are in the eye of the beholder. His “red” is my magenta.
Prickly Pear yellow, in my experience, is a light, lemony color with a faint hint of green. In New Mexico, the blooms I saw were closer to brass than lemon, an indication of age, I guess, but no less stunning. My best examples of magenta Prickly Pears are from a blistering hot day on Colorado’s Western Slope outside of Grand Junction. See my gallery here.
Prickly Pear blooms are big, up to 3 inches across. There’s something delicious about the liquid fleshiness of the petals and the way they come to a delicate point. But the star of the show just may be the large green structure in the center of the flower. Conditioned as we are to see anything like this as phallic, we can easily miss the feminist statement this plant makes. That structure is the pistil, the female organ of the plant, and all those little yellow structures bowing to it as if to a queen are the stamens, or male organs.
Of course, it takes two to tango and, in the case of Prickly Pears, after flowers and pollination, come fruits, which form oval-shaped cylinders and ripen to a dark pink. The fruits and the pads are edible. But buy your “tunas” (fruits) and Nopales (pads) in the store and watch out for the “glochids,” the clusters of tiny bristles common to the genus. Once they stick in your skin, they’re hard to remove. (4)
Prickly Pears typically bloom in May and June, and in Colorado can be found from the plains to the foothills.
NOTES:
1 Guide to Rocky Mountain Plants by Ruth Ashton Nelson, revised by Roger L. Williams (1992)
2 Rocky Mountain Wildflowers: Peterson Field Guides by John J. Craighead, Frank C. Craighead Jr., Ray J. Davis (1991)
3 Guide to Colorado Wildflowers, Volume 1, by G.K. Guennel (1995)
Here’s how we’ve absorbed the basic model of a flower without even realizing it. Because we’re expecting to see sepals, petals, stamens and pistils, we get sunflowers and their kin totally wrong. (More on sepals vs. petals here.)
I remember being astounded when a friend of mine who was getting his degree in Biology at the time told me the things I was calling petals weren’t petals at all but individual flowers. “No kidding?” I said. “Those are the ray flowers,” he said, full of the enthusiasm of the late-in-life student. “And these things? Those are the disk flowers.” He pointed at what I’d always more or less assumed was stamens and pistils but hadn’t really looked at.
“Sunflowers have two sets of flowers. That’s why they call them composites.”
Thanks to him I started seeing sunflowers and the rest of the Family Asteraceae with new eyes – and taking flower structure a lot less for granted.
Compositae is an older, still-used name for this the largest family of seed-bearing plants. It includes everything from asters to daisies, artichokes to lettuce and, of course, sunflowers.
When you’re talking Asteraceae, the proper term for all those “numerous separate flowers” (1) is a “head.” A head can consist of as many as a thousand florets, according to one source. (2)
A typical sunflower head consists of a whorl of ray flowers with “long, flat corollas” surrounding the “tubular, 5-toothed corollas” of the disk flowers. (3) I have some shots of Blanketflower (Gaillardia aristata) in my gallery that show what I mean.
On the outermost whorl of the head, where you’d expect to find sepals, there are “phyllaries” instead. These are a series of green bracts, (4) sometimes also called involucre bracts. Involucre derives from the Latin for envelop and involve, and in botany refers to “covering,” which is just the job for bracts.
To my eye, the bracts often form a sort of cup for the ray and disk flowers to sit in. There’s something about the structure, I guess, but it’s one of my favorite parts of so-called “true sunflowers,” like Helianthus annuus, the ever-present Kansas, or what my mother calls “roadside,” sunflowers. A wilder example is Helianthella quinquenervis, aka 5-nerved Sunflower.
In a plant family as large as the Asteraceae (500-plus species in the Rocky Mountain region alone), there is plenty of room for variation. Some members have only ray flowers, like dandelions. Some, only disk flowers, like thistles. In some the ray flowers are sterile and the disk flowers take care of reproduction –or vice versa. A mind-numbing number of composites are yellow and nicknamed DYFs for “damn yellow flowers” by flower buffs. But let us not overlook all the purples, blues, whites and violet hues of the genus Aster, Erigeron, Townsendia, Liatris and others.
Some composites are spring-blooming but “from mid-August until frost, the wildflower show is dominated by plants of this family,” notes Ruth Ashton Nelson. (4) In the last couple of years I’ve been surprised to see Black-eyed Susans (Rudbeckia hirta) popping up as early as late June, which I take to be an indication of a changing climate.
You gotta love a plant family that includes everything from weeds to the unassuming yet aptly named Pussytoes (Antennaria) to forest beauties like Heart-leaved Arnica (Arnica cordifolia). Take it from me, it’s worth taking a closer look at Sunflowers. You might discover a whole new world.
NOTES:
2 Guide to Rocky Mountain Plants, Ruth Ashton Nelson, revised by Roger L. Williams (1992)
1 https://www.britannica.com/plant/Asteraceae
3 Op. cit.
4 Ibid
Everybody knows what petals are. They’re the pretty stuff that make flowers flowers. We learned that back in elementary school.
But, seriously, what is a petal?
What, for that matter, is a sepal? What’s a bract? What’s this tepal you sometimes run across in field guides? How do you tell one from another? (See my gallery here and don't assume everything you see here is sporting petals.)
Let’s start by acknowledging one obvious, but somehow startling, thing. Flowers are plants’ reproductive organs. So are cones, as it happens. The angiosperms – plants that bear flowers, seeds and fruits – differ from the cone-bearers (conifers, e.g.), aka gymnosperms. But flowers or cones, it’s all about the sex.
Before sex, plants handled the whole “let’s make a baby plant” business without contributions from something male and something female. Specialized leaves called sporophylls did all the work. They produced spores instead of seeds.
“A spore is a reproductive cell that is capable of growing into a new organism or structure without uniting with another cell.”(1)
After sex – that is, after sexual reproduction evolved – making the next generation of plants took more steps and, well, more equipment, like flowers and cones. Those sometime specialized leaves evolved into petals, sepals and bracts.
Interestingly, the spore-making structures called sporangia(2) and the spores are still there. But now the spores develop into pollen in the anthers, located on the ends of the stamens (the male constituents of the flower). This is what I love about evolution. It builds new stuff from existing stuff.
Flower parts grow in whorls (i.e., rings) around the flower base – the receptacle.(3) Botanists think of sepals and petals as two of a flower’s four basic organs.
Sepals grow on the outermost whorl. They’re often green and “protect the developing reproductive structures inside the bud before the flower blooms.”(4) Think Poppies. That green fuzzy jacket around the bud before it “pops” is made up of sepals.
Next come the petals whose main role, of course, is attracting and even providing a “landing platform” for pollinators.(5) Besides advertising the flower with color and shape, petals can up the ante with “perfume and nectar glands.”(6)
But sepals can easily be petal-like in color and showiness. See Columbines. See Monkshood. They, too, can attract pollinators. Some plants dispense with petals altogether – for instance, Globeflower (Trollius laxus), Marsh Marigold (Caltha leptosepala) and Anemone (Anemone multifida globose, Anemone parviflora).
Bracts also are modified specialized leaves. Generally they’re there to protect. But sometimes they take over the role of attracting pollinators.(1,7) They can even “act as hoods or guides that can guide pollinators to a flower.”(8) The colorful, showy part of the Paintbrushes (Castilleja), for instance, are bracts. Paintbrush’s corolla (made up of fused petals) is tubular, inconspicuous and often yellowish.
“When sepals and petals are both pigmented and indistinguishable from each other, they’re called tepals.”(9) See, for instance, the garden variety Tulip or the wild Wood Lily (Lilium philadelphicum).
Petals and sepals and bracts – and, oh yes, tepals – are more than just “pretty stuff.” They have a story to tell that’s as old as evolution.
NOTES
1 “Botany for Dummies” by Rene Fester Kratz, PhD., page 81.
2 Ibid., page 87.
3 Ibid.
4 Encyclopedia of Life Sciences, http://www.els.net/WileyCDA/ElsArticle/refId-a0002064.html
5 “Handbook of Plant Science,” Keith Roberts ed., 2007.
6 http://www.ext.colostate.edu/mg/gardennotes/135.html#function
7 https://en.wikipedia.org/wiki/Bract
8 http://dept.ca.uky.edu/PLS220/Flowerbracts.pdf’
9 http://www.uky.edu/Ag/Horticulture/Geneve/teaching/PLS%20220/Flowers/Flower%20parts.pdf
One of Monkshood’s sepals does something really cool. It forms that distinctive “hood” shape that gives this plant its wonderful common name. The hood conceals a key clue to Monkshood’s heritage.
There are a couple of spurs under there – or “spurlike” petals.(1) Spurs should remind you of Columbines, of course, and also Delphiniums (Larkspurs). Like its cousins, Monkshood (most commonly Aconitum columbianum in Colorado) is a member of the Buttercup family, Ranunculaceae.
Also like Columbines and especially what I call the “big” Larkspurs (D. barbeyi and D. occidentale), Monkshood likes wet, shady places in Montane to Subalpine zones (roughly 8,000 feet to timberline). I’ve been accustomed to seeing it at higher elevations but recently I found it growing on the edges of seasonal streams at Meyer Ranch and Flying J Open Space parks in Jefferson County. Visit my gallery here.
By early August the water in these spots had stopped flowing but the ground was still moist enough to grow a few healthy Monkshood plants 3 to 4 feet tall. Seven feet isn’t unheard of for this plant whose stems can be “erect and stout to twining and reclining.”(3)
Reclining is how I’ve often seen it this year. That’s helpful for photographs – so much easier to shoot its “open racemes”(4) if it’s lying down or tipped over. By the way, my sources don’t entirely agree on whether Monkshood inflorescences are racemes or “panicles”(5) or “spike-like arrangements”(6), but you get the idea. Typically you’ll see from a couple to many flowers arranged loosely up the stem.
Aconitum columbianum flowers are most often blue – a blue so dark that some color-coded field guides group it in the purples. But – and there’s always a “but” with flora, isn’t there? – it can sometimes be “white, cream colored, or blue tinged at sepal margins."(7)
I can personally vouch for this crazy claim (a white Monkshood? Really?) because I happened on some just recently in the Mount Evans Wilderness growing near some Delphinium barbeyi. The Larkspurs were themselves notable for their unusual, at least to me, variegated cream/blue/purple flowers. Makes you wonder what’s in the water there.
If the experts don’t agree on inflorescences, they’re pretty squishy on the leaves, too. I’ve got “jaggedly toothed”(8), “toothed and cleft” with 3-5 divisions(9) or 3-7 divisions.(10) Only one source would say “palmately divided” out loud.(11) The thing to know is that the leaves are indeed deeply divided (not just in description). Without flowers, they can be mistaken for geraniums (specifically Richardson “white,” Geranium richardsonii) or superficially for Delphinium barbeyi. Craighead helpfully points out that leaves decrease in size as the stem lengthens, with the largest leaves at the bottom.(12)
At a glance, the leaves can fool you into thinking they’re “sessile” (lacking leafstalks). But it’s just the way they tuck in around the stem.
The genus Aconitum is known worldwide. Pliny thought the name had something to do with the ancient Black Sea port of Aconis.(13) North America has some 16 species. Thomas Nuttall, the enthusiastic 19th century amateur botanist and ornithologist, first identified Aconitum columbianum. “Columbianum” likely refers to the Columbia River where Nuttall traveled with the Wyeth Expedition in 1834.(14)
Aside from that hood-shaped sepal, the Aconites do have a dark side. “In various parts of the world they have been used medicinally and as a source of poisons throughout history.”(15) Colorado’s native species isn’t considered a very toxic one.(16) So, look all you want but don’t taste.
NOTES:
1 Guide to Colorado Wildflowers, Volume 2, by G.K. Guennel (1995)
2 http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=100300
3 http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=233500014
4 Guennel.
5 See Note 3.
6 Meet the Natives by M. Walter Pesman, revised and expanded by Dan Johnson (2012 edition)
7 See Note 3.
8 Guennel
9 Rocky Mountain Wildflowers: Peterson Field Guides by John J. Craighead, Frank C. Craighead Jr., Ray J. Davis (1991)
10 See Note 2.
11 Ibid.
12 Craighead.
13 See Note 2.
14 http://harvardmagazine.com/2015/05/thomas-nuttall
15 See Note 2.
16 See Note 3.
The question came up when I was talking to a friend recently about Columbines (Aquilegia coerulea). We were trying to sort out the relationship between the leaves and the flower. She hadn’t put the two together before.
“Aren’t those two different plants?” she wondered.
It’s true the basal leaves, which are lobed, don’t look related to the trio of oblong leaves nearer the bloom. I couldn’t adequately explain it, so it was time to hit the books.
Turns out it’s a case of stem vs. stalk.
The terms get tossed around somewhat interchangeably but with Columbines it helps to understand the difference.
“In a strict botanical sense, a leafless stalk of a flower is not a stem. Stems bear leaves and buds.”(1)
A stalk is a specialized stem and it’s main job is flower support.(2) Indeed, the plant matter holding up the Columbine flower is properly called a stalk. To find the stem, you have to look closer to the ground.
A stalk also can be leaf support (or leaf attachment), in which case it’s called a petiole. (If you want a great example of a leafstalk, consider rhubarb. The edible part of this otherwise poisonous plant is actually the petiole.)(3)
Stems, meanwhile, have a lot more to do than just hold up flowers. The stem carries nutrients and water between the leaves and the roots. Leaves and buds grow from its joints, called nodes. Green stems even produce food for the plant (as in asparagus, for instance). Cacti stems store water.(4)
Of course, if you want a really big, unmistakable example of a stem, consider a tree. The trunk is just a woody stem.
But stems don’t have to stand tall to be stems. The true stem of a Columbine rises only a couple of inches off the ground before branching out to basal leaves and flower stalk, if at all.
Plants whose stems hug the ground and form mats, as in the case of Sulphur Flower, Phlox or Pussytoes, are said to be caespitose or “stemless.” Besides mats, so-called stemless plants might form cushions or tufts.
Stems can even go underground. Rhizomes, corms and tubers are stems that also store food for the plant. Some underground stems make short, conical structures, “from which a crown of leaves arises. These may form a bulb (as in the onion and lily), a head (cabbage, lettuce), or a rosette (dandelion, plantain).”(5)
Just goes to show you, it’s worth going beyond that pretty flower face and taking a good look at stem vs. stalk.
Some other examples of plants with basal leaves and flowers on bare or mostly bare stalks: Shooting Star, Snowball Saxifrage, Spotted Saxifrage. Fairy Slipper bears its flower on a stem with a single basal, “ovate” leaf. For images, visit my gallery.
NOTES:
1 Guide to Rocky Mountain Plants, Ruth Ashton Nelson, revised by Roger L. Williams (1992)
2 Meet the Natives by M. Walter Pesman, revised and expanded by Dan Johnson (2012 edition)
3 http://www.botanicalaccuracy.com/2013/05/the-difference-between-stems-stalks-and.html
4 https://www.britannica.com/science/stem-plant
5 Ibid.
Field guide writers call it “showy.” I like our Colorado Blue Columbine for its sheer extravagance. Most of our natives, plant or otherwise, are a bit more modest than this. But Columbine is bold. Its blooms, typically two-toned and two-tiered, demand attention.
Here are petals and sepals both, five of each thank you very much. The petals are “scooped-shaped”(1) with spurs that narrow gracefully to a tiny knob. They start white or cream and often end pale blue, as if dipped in watercolor.
Not to be outdone, the sepals are petal-like and range the spectrum from dark, almost purple to blue to white. It’s this striking combination of structure and color that make the Colorado Blue Columbine such a stand out. But I’ve seen plenty of monotone blooms, as well. White is common but I've seen a mutation, too, that was all pale blue. Visit my gallery here.
At least one source (2) finds a relationship between altitude, color and length of spur. But easy variation is just another one of the Columbine’s extravagances and this indicates North American species evolved from a common ancestor comparatively recently (3). That ancestor likely originated in Eastern Europe or Central Asia, spreading across Beringia (the famous land bridge) to what is now Alaska some 10,000 to 40,000 years ago. The oldest species now extant in North America, Aquilegia brevistyla, is native to Wyoming and parts north, but doesn’t occur in Colorado.
Aquilegia coerulea, Colorado Blue Columbine, is native to several western states as far south as Arizona and as far north as Montana (4). Edwin James first recognized it as a distinct species. James was the very young botanist and geologist on Major Long’s expedition to the Rocky Mountains in 1820. The species name, coerulea, is Latin for blue.
Long ago, European varieties must have reminded someone of a cluster of doves (the common name derives from medieval Latin columbina for “dove’s plant.”) Some trace it to the Saxon “culfrewort,” culfre meaning pigeon (5). But when it came time to assign a formal botanical name, someone else saw eagles’ talons in its spurs, hence the derivative of the Latin (Aquilla) for eagle.
In England, the House of Lancaster and family of Derby include Columbines in their “badges.” (6) It shows up in literature, too. My favorite has to be from Ophelia’s descent into madness: “There’s fennel for you, and columbines. There’s rue for you, and here’s some for me … .” (Hamlet, IV.v.180)
Colorado Blue Columbines grow in Foothills to Alpine zones from June to August. A perennial member of the Buttercup (Ranunculaceae) family, it “prefers moist soil of ravines, rocky slopes, willow thickets, aspen groves, and forest clearings” (7).
My experience is it’s most abundant from mid- to late June to mid-July. I look for it in the aspens and other places with open or dappled shade. I’ve also seen it growing in big clumps in boulder fields near marmot dens or next to old logging stumps close to timberline.
The Columbine’s leaves are mostly basal and compound. “Leaflets [are] deeply 2- to 3-cleft and round lobed” (8). Meadowrue (Thalictrum) leaves are similar but Columbine's flowers are unmistakable.
One more extravagance of the Colorado Blue Columbine are its many yellow stamens and “five or more pistils, which ripen into many-seeded pods called follicles” (9).
Bees and bumblebees are its chief pollinators in Colorado. Hawk Moths and Hummingbirds, with their long tongues, pollinate other species common to lower altitudes. To get at the nectar contained in the spurs, bees and bumblebees chew off the knobs (10).
Some other Buttercup (Ranunculaceae) family members include: Larkspurs (Delphinium), Monkshood (Aconitum) and Pasque Flower (Pulsatilla).
NOTES
1 Guide to Colorado Wildflowers, Volume 2, by G.K. Guennel (1995)
2 http://www.fs.fed.us/wildflowers/beauty/columbines/naturalhistory.shtml
3 Ibid
4 http://plants.usda.gov/core/profile?symbol=AQCO
5 http://www.botanical.com/botanical/mgmh/c/columb89.html
6 ibid
7 Guennel
8 Rocky Mountain Wildflowers: Peterson Field Guides by John J. Craighead, Frank C. Craighead Jr., Ray J. Davis (1991)
9 Guide to Rocky Mountain Plants by Ruth Ashton Nelson, revised by Roger L. Williams (1992)
10 Ibid
All photos copyright Kristin E. Andersen
You know, there’s just one problem with field guides.
Let me back up a moment. If you’re a person who likes to walk or hike and you spend some time in places where wildflowers grow, sooner or later it’s going to happen. Something's going to catch your eye and you’re going to stop. You’re going to bend over and take a really good look at some lovely bit of plant matter.
Don’t beat up on yourself that you’ve been walking right by this thing a while – for years, for decades even – and you somehow never took a moment to really observe it. Never mind that, until this moment, all you registered was “white thing” or “blue thing” or “isn’t that pretty?” going by in a blur. It happens. Anyway, this is a famously distracted age.
The point is there comes a moment when you decide this blur must be attended to. Don’t ask me why this seems to strike many of us, mostly women, sometime mid-40s or so but it does. All I know is it’s just not good enough any more not to stop and take a look, a really good look, and wonder, “What is that?”
If you’re like me, you’ll eventually go in search of the answer as likely as not in a field guide. Because once your curiosity has been piqued, your consciousness penetrated, your habitual distraction overcome, you have to know what that is. You want names. You want facts. This is no time to be vague.
But you won’t be satisfied with just one answer. You’ll want more. Once you’ve identified that, you’ll want to know what this purple stuff is and that yellow stuff that’s everywhere and is that pink stuff indeed some sort of rose?
You may carry your field guide with you. You may take photos to go home and compare. I spent all one spring and summer getting the names in my head, only to lose them over the fall and winter. It took several years of pouring the sand in, having it leak out again before the trickier names finally stuck for good.
Several years on, here comes the problem with field guides. They don’t answer my questions any more. Oh, I still use them to jog the memory and clarify some detail. But to be comprehensive enough to be useful, guides are necessarily brief. They provide the thumbnail sketch when I want a whole biography.
So, that’s why I decided to write this blog – to fill in the details that field guides and compendia and other encyclopedic references don’t have room for. I also hope to tackle questions that botanists and other experts find too rudimentary even to consider. You’ll learn as I learn and I will try to provide photographs to learn with and enjoy.
Check out some of my wildflower photos here.