Monday, October 24, 2011

Field Notes--Orchids & Sundews of Tallulah Gorge

Tallulah River as seen from the hydroelectric station.

October 14, 2011
It is just dawn and I am riding in the back seat of the Atlanta Botanical Garden’s Subaru heading toward Tallulah State Park. The conversation up front is making me want to climb out the window.  Matt Richards and Ron Determann, ABG’s Conservatory Director, are talking about the ecological losses Ron has witnessed in 30 years of plant conservation. 

“There aren’t really any natural areas left in Georgia.  Not really,” he says. “Just pockets with refugia of rare plants.”

The main problem, as he sees it, is the heavy use of herbicides used to control weeds along roadsides, under powerlines, and even along paths in natural areas visited by the public.  The method formerly used, which is less destructive, is mowing.   But that takes more people and equipment, plus you have to mow more often than spray—at least initially.  The result, according to Ron, has been the destruction of most roadside ecology. 

Sarracenia leucophylla, Conservation Garden @ ABG
Now, you might not think that native plants, and certainly not rare plants, grow in highway medians or under powerlines, but they do. The white-top pitcher plant (Sarracenia leucophylla) was thought to be extinct in Georgia until it was found growing in a powerline right-of-way in 2000.[i]  Similarly, one of the few Georgia populations of Tennessee yellow-eyed grass (Xyris tennesseensis) clings to the greenspace in a highway off ramp.[ii]   

As counter-intuitive as it seems,  nutrient-poor sites also harbor greater biodiversity.  Repeatedly spraying for weeds builds up decaying vegetation, which enriches the soil making it more hospitable for weedy growth.  So instead of a diverse roadside ecology, you get a few species of invasive weeds growing lush and tall.  Naturally, the invigorated weeds require more frequent of spraying.  And so it goes.

The other nasty side-effect of using herbicides is the harm they can do to amphibians.  Herbicides with surfactants are not to be used in wetlands, but they very often are.  The surfactants clog the breathing pores of frogs and other creatures, killing them.

In addition to weed suppression, herbicides are injected into tree stumps to prevent re-sprouting.  The practice is thought to be safe for the creatures that live around these stumps, but Ron doesn’t think so.  He describes finding skeletons of 30 year-old bog turtles that died after stumps around their habitat had been poisoned.

At this point in the conversation, I can take no more. It’s barely light out, and in the morning I am especially vulnerable to despair.  I pull photos of plants on my phone for Ron and Matt to identify. It’s not that I don’t want to hear it; I just need my doses of toxic knowledge at non-lethal levels.


Ron Determann: Conservationist & horticulturalist extraordinaire.
Today we will not be visiting a roadside refugia, but climbing into Tallulah Gorge, one of Georgia’s most beautiful places, to look for the monkeyface orchid (Platanthera integrilabia) and some of its friends.  We hope to collect seed to bring back and grow in the tissue culture lab.  We’ll keep some seed and plants for back up and outplant seedlings to augment the natural population.  Growing things is Ron’s especial gift.  He has brought rare and endangered plants into cultivation that no one else has been able to grow.  The tissue culture lab that Matt runs at ABG is named after Ron.  

The tram making its very slow yet precipitous journey.
The orchids were sighted growing near the floor of the Tallulah gorge, nearly 1,000 feet down, alongside the Tallulah River.  The river is no longer the roaring terror that earned it the name “ the Niagara of the South.”  Dammed in 1913, the Tallulah River’s six falls have been quieted.

Nevertheless, we still have to find a safe place to cross the river to reach the orchids.  Brian Estes of Georgia Power knows just the spot and he's arranged a special treat for us.
Almost there. See the folks at the bottom?
We are taking the a tram that runs strait down the face of the gorge to the hydroelectric station below.  Hiking down would be pleasant, but that would take three hours round trip, leaving less time to hunt orchids.   

Climbing into the tram we are initially cautious of the open doors but are soon hanging out the sides taking photographs of the odd combination of flora growing on the slope:  natives, exotic invasives, and wetland plants taking advantage of the water flowing from tiny leaks in the penstock pipes that take water down into the hydroelectric turbines. 

Forging the Tallulah River
Our ride over, we leave the tram and put in earplugs so that we can walk through the noisy power station and begin our final descent into the gorge.  Soon we are scrambling over rocks and through trees and shrubs looking for a shallow place to cross the river.  Brian finds the spot and one-at-a-time we make our way through the water and over the rocks slick with moss. 
We are on the other side less than three minutes before Matt finds orchids.  We collect seed capsules and move to another spot.  The growth of shrubs is dense and the footing is uncertain, and everyone manages to grab hold of poison sumac at one time or another.  Having inadvertently nuzzled the stuff, I have a vision of my face 3 days from now erupting into painful blisters.  

Poison sumac in its autumn colors.

I next see my companions gathered at a seep where water has collected into what looks like a shallow pool but Brian has warned us is actually waist-deep silt.  Matt and Ron collect more seed.  I see Parnassia asarfolia in bloom, which I saw for the first time last week while collecting Isotria with Matt.  We thought we’d have time to stop and take photos on the way out, but no such luck.   
Parnassia asarfolia
While I am carefully photographing the exquisite blossom, the rest of the group continues the ascent.  The next thing I know I am alone.  I start to climb and call, climb and call.  At last I hear an answering voice.  By the time I catch up, I’ve lost my lens cap and some of my composure.  My hair is full of twigs and leaves. 

Everyone is standing around what may be the same seep only much higher up.  Sphagnum moss grows thickly at the edges of the wet rock face, and on the face itself are tiny round-leaf sundews, Drosera rotundifolia.  The red hairs on their leaves glisten with mucilage, a sweet but also sticky substance that lures insects to their doom.   
Sundews appear to be growing in light film on rock face.
Once stuck, the hairs bend inward and the leaf begins to fold over the insect. Meanwhile glands on the hairs secrete enzymes to dissolve and digest the insect.  Several days later, the meal complete, the leaf will unfold, ready to ensnare its next victim.  Carnivorous plants live in nutrient-poor conditions like this seep, catching and eating insects to supplement their diet.

The Drosera rotundifolia growing so abundantly in this seep is the same species of sundew that Charles Darwin prodded with everything but the kitchen sink.  To see what would make the sundew move, Darwin placed in its hairs—he called them tentacles—meat, dead flies, bits of paper, wood, dried moss, sponge, cinders, chalk, wadded strands of hair, and shards of glass.  What he found was that when repeatedly touched by minute objects, the tentacles would invariably enfold the object.  Meat, egg, and, of course, insects the plants retained and flooded with digestive enzymes until consumed. Innutritious material like glass and cinders the leaf released.

(Drosera rotundifolia)
Leaf (enlarged), tentacles on one side inflected over a bit of meat placed on the disc.
 From Charles Darwin's Insectivorous Plants (1875).  Drawing by his son George.
In Darwin's experiments not every touch resulted in movement.  Drops of water and other heavy pressures did not cause the tentacles to bend. Darwin concluded that thanks to this selective sensitivity “the plant is thus saved from much useless movement, as during a high wind the glands can hardly escape being occasionally brushed by the leaves of surrounding plants.”[iii]

Matt pointing to a sundew and not sliding down the cliff.
I did not stop to poke the sundews.  Nor did I look to see what prey they grasped in their hairs.  I concentrated on staying more or less upright.  Ron, however, did slip a few specimens into a bag.

In total we collect seed from five orchid species:
Platanthera integrilabia     Monkeyface orchid
Platanthera clavellata        Small green wood orchid
Pogonia ophioglossoides    Snakemouth orchid
Calopogon tuberosus         Common grass-pink
Malaxis uniflora                 Green adder’s-mouth orchid

Snakemouth orchid, Pogonia ophioglossoides
The snakemouth orchid (Pogonia ophioglossoides ) and the common grass-pink (Calopogon tuberosus) were especially exciting to find growing in Tallulah Gorge.  Both orchids are common in Georgia’s coastal plains, but this is the only known mountain population of each species.   

The seed can be grown into plants, and then the plants can be placed in mountain bogs that the Atlanta Botanical Garden is restoring.  The ideal is to grow material from the recovery location and return the plants to the original site to augment the natural population.  In the absence of such material, you can at least strive for a kind of genetic authenticity by using plants from the same kinds of locations, in this case mountain locations. As Ron says, “We don’t like to put Okefenokee orchids in mountain bogs, even if they are the same species.” 

“I could stay here all day,” Matt enthused.  No doubt he could, but it was time to start heading out.  

Ron with our guide, Brian Estes of Georgia Power

[i] Chafin, Linda G. Field Guide to the Rare Plants of Georgia. Athens: University of Georgia Press, 2007.  p. 446.
[ii] Chafin, Field Guide p. 434.
[iii] Darwin, Charles R. 1875. Insectivorous Plants. London: John Murray. p. 264

Sunday, October 9, 2011

Field Notes: Hunting for Orchids and Indian Pipe

October 7, 2011
I am riding north with Matt Richards, the Atlanta Botanical Garden’s Conservation Coordinator and orchid specialist.  We are headed to Georgia’s gold country.  It is also orchid country, where both yellow and pink lady’s-slipper flourish, and where the remaining populations of rare orchids species can be found—if you are lucky.  The orchid we are looking for today is Isotria medeoloides, or small whorled pogonia.  The U.S. Forest Services has been monitoring the plant for the past 15 years, and its numbers have been in steady decline.  
Isotria medeoloides in bloom.  Photo: Dennis D. Horn.
Our first stop is a gas station in Suches, which boasts the highest elevation of any Georgia town (just shy of 3,000 feet).  In my experience, fieldwork meet-ups tend to be at gas stations, which is convenient since you get one last visit to the bathroom and a chance to buy water and other provisions before entering the woods.  Deciduous forests aren’t the greatest for finding secluded spots for a bare-bottomed pee, especially if you are with a group that has split up to search for plants. 
We don’t have to wait at the station for long before Mike Broe arrives.  Mike is a Ph.D. student at Ohio State University working on Indian pipe, a kind of mycotrophic ("fungus feeding") plant that has no chlorophyll and spends most of its life underground. Green plants are called “autotrophs” because they are capable of feeding themselves given sun, water and carbon dioxide.  Mycotrophs take advantage of the symbiotic relationship between trees and mycorrhizal fungi.  Mycorrhizal hyphae (fungal threads) enter into the roots of the trees and the trees benefit from the increased surface area of their root system.  The trees absorb more water and minerals, and the fungus receives nutrients from the tree.  Like a little thief, Indian pipe taps into this symbiotic apparatus, reversing the flow of carbon and other nutrients to meet its own needs.

A more common Indian pipe, Monotropa uniflora, also called Ghost plant.
The only time Indian pipe and other mycotrophic plants are visible is when they flower, pushing mushroom-like through the forest duff.  The kind of Indian pipe that interests Mike is Monotropa hypopitys.  Its flower is a pale creamy white, coral pink or red.  On a recent orchid-seed collecting trip, Matt saw populations of very deep red M. hypopitys similar to ones Mike has observed in Maryland and Ohio.  From his studies of the morphology and DNA of the plant, Mike has reason to believe that this southern population may be a distinct species. When he has looked at specimens under a microscope, Mike has seen white hairs around the stile that are not present in M. hypropitys of the north: “The white hairs are very striking against the red, like Santa’s whiskers.”

Matt (right) showing Mike where we are on the map.  Better than leaving breadcrumbs.
The trail Matt leads us down is densely forested with pine and hemlock and overhung with rhododendron, creating the gloomy atmosphere favored by Monotropa.  It isn’t long before we spot the red flower spikes of M. hypopitys—as it is called for now.  After Mike’s work, it may be assigned a new classification.

M. hypopitys in its red glory.
 Mike is delighted at what he sees.

“Need anything else?  You want help finding your way out when you’re done?” Matt asks before we leave him to it.

“No,” Mike replies, “I’m in hypopitys heaven!”

Our next appointment is with Ronnie Ensley, our guide to the area’s Isotria populations.  Ronnie worked for the U.S. Forest Service where his job was to look for federally protected plant species on land slated for logging.  “I was the only one to apply,” Ronnie told me.  “I learned on the job.” 
Matt has great respect for Ronnie.  “There’s a generation gap between guys like Ronnie and me.  He’s gotta be at least 70, and what he knows nobody else does.  When he’s gone, that it.  It’s important to get out there with him and transfer some of that knowledge.”

Our quarry, the orchid Isotria medeoloides.  Can you see it, the light yellow, five-petaled plant in the middle?
Isotria flowered back in May, so we are looking for what remains of the plant, hopefully with seed capsules intact. It’s a small plant and is especially hard to spot in its spent state.  Also, Isotria often grows among wild cucumber, which has a very similar look.  Not every plant flowers, and in a poor growing season, fewer plants come up at all.

The site of our first search for Isotria.
The first location Ronnie takes us to is a lovely little creek-side slope.  After a search we find lots of wild cucumber and only two Isotria, neither of which have seed capsules and don’t look like they ever did.  We also find a three birds orchid, Triphora trianthophora, which bloomed somewhere between July and September.  The flowers last just a few days and are open only from midmorning to midafternoon.  Triphora in bloom is a truly rare sight.

Three birds orchid with seed capsules.
We drive to another spot and park.  Here we put on orange vests since it’s hunting season.  Rifles are banging away in the distance.  We hike into what was once a road, which is now over-grown with shrubs, sapling tulip poplars and baby hemlock.  Ronnie takes a turn off the path and heads into the forest.  How does he know where to turn?  He doesn’t use GPS or look at a map he’s marked.  Matt and I are baffled.  He just walks right up to the spot where he’s seen Istoria in the past. 
After a bit of a search, we find an Isotria with seed capsules intact. 
“You’re gonna decapitate it, aren’t you?” Ronnie asks Matt.  “I can’t watch.”

Our guide, Ronnie Ensley in the foreground.
Matt assures him that he’ll only keep around 10% of the seed.  The rest he’ll disperse in the same spot, some as raw seed and some in prepared packets to bait the fungus Isotria needs to grow.  What Matt keeps he will try to grow in the tissue culture lab back at the garden, and some will simply be stored as back up against extinction. 
At the last site I actually find an Isotria with seed.  I am quite pleased with myself since it is particularly ratty and difficult to see.  I consider myself extremely lucky to be able to come along on fieldwork.  As I see it, my first duty is not to get in the way.  My second is to be a pleasant traveling companion.  I feel especially glad when I can actually be of some use. 

Our last Isotria of the day and my first find.
 We hike back to our vehicles and part ways with Ronnie.  It’s been a good day.  We found what we were looking for—which happens as often as not in Matt’s line of work—and we collected seed. As we motor through the countryside, Matt grips the wheel and exclaims, “There is no way I could have found those plants without Ronnie.”

Wednesday, April 27, 2011

Freya & the Phoebes

I know this is floraphile, but occasionally I have to report on fauna.  
A pair of Eastern phoebes set up housekeeping in the eaves just above my office window, a circumstance both enchanting and stressful.  
The nest:  a sturdy structure mostly of mud.
Being flycatchers, Phoebes go from perch, to a quick flit, to a mouthful of insects in seconds.  They are like bats without the nighttime equipment, or swallows minus the acrobatic soaring.  Phoebes are small, unassuming birds, but doughty.  One afternoon I saw a mockingbird uncomfortably near the nest going through its repertoire of aggressive calls.  Undaunted, the phoebe planted himself just feet from the mockingbird, his tiny chest hugely puffed out.
The redoubtable phoebe outside my window.
The stressful bit has been my cat Freya’s too-avid interest in the birds.  Sitting transfixed in the window seat is acceptable; climbing the screen to get a closer look is too much. 
Tireless ornithologist?  I think not.
Bad animal.
As a deterrent I kept a spray bottle on the desk, but Freya just couldn’t help herself.  A phoebe would come flying in and she’d be up the screen like a caged monkey.  I’d squirt Freya and she’d run into the hall, where she’d regard me with hard-eyed outrage.
They call me The Enforcer.
I was afraid that the birds might abandon the nest, so Freya was banished from my office.  She now lodges her complaints at the closed door.  Alternately Freya assures me that she just wants to put the phoebes in her mouth.  Just for a minute.  No harm done.   
For a time I couldn’t see the mother’s tail poking out from the nest, nor did I hear any babies.  I feared the worst.   So it was with great relief that I saw the parents, their beaks stuffed with insects, fly into the nest, and then heard the screechy delight of baby birds.

Saturday, March 26, 2011

An Evening with Pearl Fryar

Where has Floraphile been? you ask.
She’s been busy getting an education through the Master Gardener program offered by University of Georgia’s Cooperative Extension.  And she’s been grieving the loss of her cousin/friend/inspiration Karen Hart (a.k.a. li'l hateful).  
Karen (on the right): You are daily missed.
But Floraphile is back with you, revived by a good friend who took her to see Pearl Fryar speak at the Georgia State Botanical Garden a week ago.  Let me tell you, Pearl Fryar is exactly the person to shore up a soul forlorn and broken-down by grief. 
So who is this Pearl Fryar?  Well, he’s an artist, humanitarian, and gardener who for nearly 30 years has been making abstract topiary in his yard in Bishopville, South Carolina.
Now, I don’t want to say too much here because there is a very fine documentary called A Man Named Pearl that you really should see, especially if you are in need of spiritual uplift.  What I will tell you is that nearly all the topiary in his garden started as plants Mr. Fryar retrieved from a local nursery’s rubbish heap, where plants too sickly or misshapen or otherwise unprofitable were discarded.  He took home these “throw-away plants,” generally no larger than one gallon, grew them and trained them in to the fantastic shapes that now make up his three-acre garden.  His only training in topiary was a brief demonstration at a nursery.  
 “Everything here I’ve done with my gas-powered hedge trimmer.  I can do miracles with my hedge trimmer.”
That might sound like boasting, except that it’s true. Actually, this claim, made largely in jest, falls short of the miracles manifest in Mr. Fryar’s garden.  From a horticultural standpoint, a number of plant species thriving in the garden shouldn’t be able to grow there at all, or at least not in the forms into which they’ve been trained.  For example, because the family’s Christmas trees were added to the garden, you’ll find Frasier fir and Norway spruce, neither of which is supposed to grow down in South Carolina.  You’ll also find live oaks in the most improbable shapes:  dense cubes and mushroom caps, graceful trunks and branches adorned with leafy tufts.  And all of this is done without chemicals and with little watering beyond what it took for the plants to initially establish themselves.  

“Sometimes you gotta substitute for what you don’t have.”
Mr. Fryar now has a cherry-picker to carry him to the tops of his larger creations, but that was not always the case.  In his presentation, he showed us some slides of himself atop a ladder stretching obliquely from where it rested on the bumper of his truck or wedged between the truck’s cab and camper shell.  “If OSHA came by and saw what did, I’d probably be under the jail,” he quipped.  
Despite some really heart-stopping acrobatics, Mr. Fryar has never fallen.
Mr. Fryar generally used what was to hand.  For instance, to train plants into arches he uses PVC pipe.  To create an espalier against his house, he used nails and pantyhose (although he recommends getting permission first, as his wife was none too pleased when it was time to dress for church and her hose had disappeared).  He joked that he used to use string to train plants, but now that he wants to “look professional” he uses zip ties instead.  “If you took away Yaupon holly, PVC pipe, and coat hangers,” he reflected, “I wouldn’t have a garden.”
Once the shrubs have grown together and the arch is complete, you can remove the PVC.
Art and repurposing aren’t limited to topiary for Mr. Fryar.  He’s also a junk-metal artist.  Like his plants, these pieces are whimsical, elegant studies in form.  He showed us slides of his metal art and paused at one slide to remark, “I don’t own this piece anymore.  A woman caught me at the right moment.  I think I needed a new tractor.”  But he wasn’t bitter about it.  In fact, shortly there after he advised, “If you want to be successful, create something the ladies like.”
Fountain: An example of Mr. Fryar's "junk art."
Mr. Fryar finished his talk with a demonstration.  He applied his hedge trimmer to two Leyland cypresses, turning them into handsome spirals.  He also gave advice to those of us who wanted to try our hands at topiary:
Start small.  Fryar recommends starting with one-gallon plants, because you cannot adequately control the growth of larger plants.
Dig a trench.  Once you have your plant in the ground, encircle it with a trench.  According to Mr. Fryar, “Once the surface roots go in the trench, they don’t come back up.  That way I don’t have to water.”  He also mulches around the plant with pine straw. 
Don’t skimp on hedge trimmers.  With cheap hedge trimmers, you have to repeat your cuts:  “If you have to go through 2 or 3 times, you are damaging the plant.”  Fryar realizes that “most people don’t want to spend $400 dollars for a hedge trimmer” like his, but he urged the audience to spend no less than $100.
Cut new growth every 4-6 weeks.  “If you have to rake clippings, you’ve waited too long.”  With a frequency of 4-6 weeks, you can control the plant’s growth.
Choose a style.  “My style is abstract free-form.  I want to see the structure of the plant.”  This style has its benefits as you can “make a mistake into art.”  (Well, Mr. Fryar can, anyhow.)
Avoid disease-prone plants.  Mr. Fryar no longer uses boxwood, a shrub traditionally used in topiary, because it is prone to spider mites and diseases that require the application of chemicals.  If you want the boxwood look without the problems, he recommends Yaupon holly.
Make left-handed friends.  If you, like most people, are right-handed and want spirals that mirror one another to place on either side of a pathway, you are going to have to find someone left-handed to make the opposing spiral.  He recommends taking your left-handed friend out to lunch, and then teaching him or her to use your hedge trimmer.  
An artist at work.
Looking at Mr. Fryar's creations can be intimidating.  That is always the case when regarding an extraordinary artistic achievement, and then setting about to make something of your own.  Nevertheless, Mr. Fryar has inspired many of his neighbors in Bishopville to practice topiary, and the influence of his style is evident in their creations.
Apparently topiarius, Latin for "ornamental landscape gardener," means creator of places, topia being the Greek word for place.  Into his lawn Mr. Fryar has carved in words and spelled out in flowers Love Peace + Goodwill.  I have no doubt that a visit to his topia awakens those sentiments, as does being in the presence of the man for an evening. 
Pearl Fryar signing after his talk.  That's his wife Metra.
Again, I highly recommend seeing A Man Named Pearl.  But until you get your hands on a copy, watch this John Deer spot featuring Mr. Fryar.  It's worth it to hear his remarkable voice and see more of the garden. 
Floraphile extends a special thanks to Jenny Cruse-Sanders.

Monday, January 10, 2011

The Cycad Chronicles, Part 1: Prehistory

Behold, the cycad.
Encephalartos villosus in Desert House of ABG. Photo: Hilary Hart.
That's right, this is not a fern but a cycad.  These plants vary in size from towering trees to ground-hugging shrubs.  Their leaves can be delicate and feathery and also thick, tough, and cruelly armed.  In fact, my first formal introduction to a cycad began this way:  “Watch out for that one.  It’s a real bastard.”  In this case, Conservatory Manager Paul Blackmore was referring to a rather spectacular specimen of Encephalartos horridus in the Desert House.  It’s not a plant you want to brush up against.  Its dense, entangled foliage is lined with wicked spines. Horridus indeed.
Encephalartos horridus. An embrace to be avoided. Photo: Hilary Hart
Most cycads, however, are content to greet the world sans piercing spines. While they often resemble palms or ferns, cycads are related to neither.  In his foreword to David L. Jones’ important work Cycads of the World, botanist Dennis Wm. Stevenson laments this confusion while expressing gratitude to “the native people who always know where to find” cycads in the wild. “And without taking one to palms!”  Indeed, a number of cycad species develop palm-like crowns atop tall stems that resemble enormous trunks.
Cycas angulata near Borroloola, Austrialia. Photo: Len Butt of PASCOA.
Cycad Madness
I was unaware of cycads until volunteering at ABG.  When I thought I’d bone up on the plant, I had no idea I was flirting with obsession.  The signs, however, were soon apparent: The piles of printed journal articles, the unswerving cycad monologue, the caressing of sago palms in Home Depot.  “Did you know they’re really cycads, Cycas revoluta?” I heard myself asking uninterested shoppers.  
Sago palm aka Cycas revoluta available at Lowe's or Home Depot.
It was Mike Wenzel who gave me the clue that my new-found passion was trite, at least among floraphiles.  It happened while Julia Rittenhouse (Conservatory Horticulturalist) was repotting cycads for a display in the Tropical Rotunda.  Mike stopped by and casually asked Julia:
“Are you mad for cycads yet?”
“No,” Julia replied. “Just mad from being poked all over.” 
That took me down with a bump.  This exchange taught me two things: Cycads commonly ensnare the susceptible, and not everyone is susceptible.  Not really a problem, except when it comes to writing about cycads.  In my state of cycad enchantment, how can I discern what will interest the unafflicted, when everything about them fascinates me?  Perhaps now you can understand why it has taken me so long to publish this floraphile entry.

Cycads are very, very old.  They were here before humans, before dinosaurs, and before most of the plants that are common today.  While they now grow in pockets in the tropics and in subtropical regions, cycads once were everywhere on the globe.  And because they were so populous, cycads have left a comparatively prolific record of themselves in fossil form.  These fossil cycads in turn allow us to imagine what the world once looked like and theorize about how it has evolved. 
Here’s an example of a cycad fossil, actually the best example of a cycad fossil because it is the whole plant including a male cone.

Megafossil of whole plant cycad. Collected in 2009 from the Yangcaogou Formation (Upper Triassic) in Changheying, Beipiao, Liaoning. Related to living Zamiacea.
As you can imagine, plants are quite a bit more fragile than bone, so they tend to fall to pieces more easily.  Such a large intact fossil is thus far unique.  Moreover, this fossil is from the Late Triassic, which means the plant was alive 200-250 million years ago.  Many of the first dinosaurs evolved during the Late Triassic.  And, while the fossil was discovered in what is now China, Asia was still part of the undifferentiated supercontinent Pangaea when the living plant first broke ground and lifted its leaves skyward.
Meyers Konversationslexikon, a German encyclopedia, 4th edition (1885-1890) Plate title: "Life restaurations of some Triassic plants." 

The Age of Dinosaurs/The Age of Cycads
As a species, cycads reached their hey day around the 150 million years ago, during the Jurassic Period.  And as any grade-schooler will tell you, this is the Age of the Dinosaur, the glory days between extinction events.  Consequently, many refer to the Age of the Dinosaurs as the Age of the Cycads (although I don’t think this nomenclature is really going to catch on with the kids).  Dinosaur and cycad fossils have been found together.  Moreoever, if you have ever wondered what dinosaurs ate, you can be nearly certain that cycads were on the menu.  Hence, any Jurassic diorama worth its salt should include cycads.
To solidify the connection between dinosaurs and cycads, here is a National Park Service poster:

Where is this wonderful Fossil Cycad National Monument?  It was in the Black Hills of South Dakota from 1922-1957.  Alas and alack, it is no more.  But for mismanagement, we might have had a National Park dedicated to cycads with in situ specimens.  This loss seems especially poignant to me because the South Dakota landscape out of which these fossilized tropical plants are retrieved brings home how vastly different the world once was in a way that no museum diorama or artistic rendering can.  The latter might as well be depictions of other planets.  To see a fossil in situ would give the intervening eons dimension. And the living cycad, with its striking resemblance to fossilized cycad remains, animates the continuity between the prehistoric world and now.
Paleobotanist George Reber Wieland supervising a CCC crew during the 1935 fossil cycad test excavation (Yale University).

A World Before Flowers
Now if we are to have an accurate Jurassic diorama of the mind, we should probably consider some other flora.  When the cycads were at their most flourishing, around 150 million years ago, the climate was warm and moist with just a few arid spots.  As a result the world grew luxuriant with vegetation from pole to pole. (In fact, one reason that the climate is thought to have been almost uniformly tropical is because cycad fossils have been found in both Greenland and Antarctica.)  Also in abundance were other gymnosperms: ginkgoes, and conifers, including close relatives of living species of redwoods, cypresses, pines, and yews.  Cycads were dominant, that is until the late Cretaceous Period, when a new group of plants emerged, the angiosperms, otherwise known as flowering plants. 
These showy upstarts had a number of advantages over cycads and the other gymnosperms: They grew faster, matured sooner, and because their seeds are pollinated in an enclosed in an ovary they could survive broader dispersal. (The term “angiosperm means “enclosed seed while “gymnosperm” comes from the Greek word for “naked seed.”) Flowering plants very quickly eclipsed the gymnosperms.  Where once much grew but nothing bloomed, today flowering plants make up about 95% of all land plants. 
So if your Jurassic imaginarium features the gentle brontosaurus feeding on a gigantic blossom, please revise.

More likely.  Artist: Karen Carr.

Surviving to the Present
If the angiosperm overthrow weren’t enough, cycads were also up against continental drift and glaciation. As the theory goes, around 180 million years ago, the supercontinent Pangaea split into Gondwana in the south and Laurasia to the north.  Laurasia, though changed in shape, remained intact except for North America. Whereas, Gondwana broke apart into the landmasses that appear today’s maps as Australia, Africa, South America, Antarctica, India, New Guinea and New Zealand.  Continental drift is slow enough to accommodate adaptation, but the turn in the weather during the Pleistocene Period caught a lot of flora and fauna by surprise.  The rapid advance of glaciers carried off a lot of megafauna, including mammoths, mastodons, saber-toothed cats, and the Neanderthals. Where the glaciers made their bid for lebensraum, you will not find living cycads, only fossils.  Consequently, cycad distribution today looks like this:  

Cycads generally occur between the Tropics of Cancer and Capricorn, or between 30 degrees north latitude and 35 degrees south latitude.
Calling the cycad a "living fossil" suggests that the plant has changed very little from the versions of itself that lived millions of years ago.  And this is true of some of the species of cycads.  Those that continue to live in the warm humid conditions that prevailed in the Jurassic and Early Cretaceous Periods, like the Cycas revoluta I visit at Home Depot, are considered more primitive. In fact, compare the complete fossil from the Triassic to the Home Depot sago palm. Similar, no?

But many species of cycads have adapted to live in very different climes. The Encephalartos species that grow in the xeric Cape region of South Africa, like my horridus friend in the Desert House, are truly the tough cookies of the genus.  They have adapted to a hard-scrabble life by soaking up and storing water when it does fall, and growing spines to fend off the predations of animals that would like very much to feast on them.
Had cycads remained truly unchanged they would never have survived.  They would have gone the way of the dinosaurs or much of the North American megafauna of the Pleistocene: extinct despite their charisma. 
Finally, part of what draws me to the cycad is that to learn its story is to learn the story of the planet. And I fit into that story too.  Humans may have arrived late on the scene, but we have evolved alongside the cycad to survive to the present not as artifacts, but as living creatures. 
The greatest delight which the fields and woods minister, is the suggestion of an occult relation between man and the vegetable.  I am not alone and unacknowledged.  They nod to me and I to them.  The waving of the boughs in the storm, is new to me and old.  
-- Ralph Waldo Emerson from his essay Nature.