Thursday, October 28, 2010

Grand Canyon Part 5: The River

IMG_7588We moved our camp down to the next- and only real other- junction in Tuckup, that of the main canyon and the Northeast arm, pausing to down-scrabble and hand off packs several times. Shortly before arriving at the junction, we passed under a feature I’ve encountered spanning no other canyon on the Colorado Plateau: a conglomerate arch.

I explained conglomerate rocks last year closer to home, in City Creek Canyon. The hunk of conglomerate that the arch is carved out of is similar, though I’m sure it formed at a different time. But I don’t know when it formed. I suspect it was deposited in an existing channel in the Muav, but at a much later time than the Temple Butte formation we scrambled up in the last post. But I haven’t pinned it down in any of my geo sources*.

*My best guess is that it was deposited in the last million years. I know that there are deposits from basalt flows in Tuckup and its tributaries laid down between 700K and 1M years ago. The arch/bridge appears to be made of conglomerate, not breccia**, but I wonder if some of the eruption and flow events of that period could be related to the deposits that formed the conglomerate. Just a hunch.

**Which I explained in the same post.

IMG_7598 In any case, it’s not technically an arch, but a natural bridge, in that water runs under it. Specifically it’s a waterfall natural bridge, a type that is created by subterranean stream piracy*, which is a fancy term for when the flow of a stream gets diverted underground into openings/crevices beneath. The flow eventually undercuts the surface, leaving a bridge supported by the former stream banks.

*Is that the coolest term ever or what?

SS Piracy The arch looks crumbly and fragile- like it’s going to fall on you any minute. Guidebook author George Steck claims that it’s stronger than sandstone, but The Natural Bridge and Arch Society* calls it a “relatively fragile structure.” In any case, we didn’t try jumping on it.

*Man, it is like there is a society for everything.

IMG_7687 Our new camp was one of the coolest sites I’ve ever camped at, on ledges maybe 30 feet above the canyon bottom, with easy access to water, plenty of flat space for sleeping (pic left = my sleeping bag on ledge), cooking and lounging, and an overhang for rain protection (not that we needed it.) And the view from the “porch” was fantabulous, though our night sky was just a narrow band between the canyon walls. Ledge sites are nice also because you cook and sleep on rock, not sand, which means that everything- you included- feels clean, not gritty. If the site had any logistical downside, it was the necessary hike/scramble to access enough soil to dig a cat-hole*.

*To, you know, poop.

Side Note: While I’m on the topic, decent campsites in Tuckup Canyon are extremely limited. Bed viewThis is because the canyon is narrow pretty much the whole way from about a mile below Shaman’s Gallery on down to the river, which makes for great hiking, but tricky bedding. Really the 3 main camp-able spots are the junction with Cottonwood Canyon, the junction with the Northeast arm, and the beach on the river. Fortunately the Park Service limits the number of backpackers in the canyon via a permit system, but competition for sites is still possible.

ASteve hole caption We spent the afternoon exploring the Northeast arm, a fun scramble of ledges, chutes, pools and tunnels, before returning to camp, eating and crashing.

Side Note: Something else about camping. It was remarkable how much warmer the nights became as we progressed down-canyon. Thursday night up on the rim at ~5,800 feet there was frost when I awoke. At the Cottonwood Canyon junction (~2,700 feet) it got down into the low 50’s. At the Northeast arm junction (~2,100 feet) it didn’t get below 60F the whole night. Oddly, the days were still quite pleasant, never above ~75F.

IMG_7557 The next morning we packed lunch, rope, a couple of carabiners and headed down-canyon. By this point there was water pretty much continually, and after a couple of miles we reached a deep pool with a little waterfall that looked difficult to climb back out of an the return. Bright Angel We backtracked a short way and found a faint bypass trail that soon climbed high up above the canyon bottom. The (very exposed) trail followed a sloping band of shale-y soil that I realized was the Bright Angel Formation, consisting of extremely fin-grained shale laid down some ~515 - 530 million years ago that always forms slopes, erodes easily, and sometimes has a faint green-ish tinge. The green color comes from Glauconite, which is a kind of mica that forms in sediments either as or after they transform to solid rock.

IMG_7669 Side Note: We passed under a huge, exposed hanging garden here, probably fed by seeps occurring where the Muav limestone meets the Bright Angel shale.

Dropping back into the canyon bottom, we were on/in rock again, but now a different rock- the Tapeats Sandstone. Tapeats, laid down ~530 – 545 MYA is thought to have been formed in tidal flats, tidal channels and beach deposits in and by a IMG_7666Cambrian sea. It features frequent ripple marks and trilobite fossils. From a hiker’s perspective, it seems to erode into many, many horizontal ledges, forming open plazas separated by repeated staircases. In spots where it gets steeper, the ledginess provides ample finger and toeholds.

In and by the larger plaza-pools, we began to notice a number of toads, which on closer inspection, were decorated with bright red spots. IMG_7665 These are Red-Spotted Toads, Bufo punctatus, and they are opportunistic breeders of the desert Southwest. Normally nocturnal, they became unusually active following rains, quickly mating and laying eggs in pools. The eggs hatch in about 3 days, and mature into toads in 6-8 weeks. The same rains that caused us such trouble on the drive in were the reason we were seeing so many of them now by day. They don’t “croak” like traditional toads, and we thought them curiously silent. But later I learned that their “croak” sounds more like the high-pitched “chirp” of a cricket, and that perhaps a few of the occasional “crickets” we heard in the evening were actually male Red-Spotteds seeking mates.

Red Spotted caption Bufo is a huge genus, with around 150 species occurring worldwide. As a rule they’re lousy jumpers (especially compared to frogs) and the Red-Spotted Toad tends to walk/shuffle more so than jump (they’re ridiculously easy to catch.) To compensate for their lame mobility, many Bufo species exude defensive, toxic skin secretions. Bufo boreas, for example, the common and widespread Western Toad (which you’ve undoubtedly seen if you live in the Western US and often hybridizes with B. punctatus) produces skin toxins that repel many predators. Other species produce skin poisons that can kill a large mammal that eats them, and some of these poisons, such as that secreted by B. alvarius, the Sonoran Desert Toad, are hallucinogenic (leading to the whole licking-toads-thing, which- like Datura- I recommend you not mess around with either.) But Red-Spotteds produce no such toxins that I’m aware of (which is maybe why they’re nocturnal).

IMG_7636 One of the interesting things about a worldwide genus is where it came from. In the case of Bufo, this question has been the subject of various hypotheses for decades. The greatest diversity of species seems to be in South America and Africa. One hypothesis was that they originated in Africa, spread throughout the Old World, and then migrated to the Americas via (an earlier incarnation of) the Beringian land bridge. Another proposed the exact opposite, with a South American origin. But more recent genetic evidence seems to suggest elements of both, and yet neither, hypotheses.

Apparently Bufo originated in Gondwanaland back when South America and Africa were either still connected, or close enough for them to spread between the 2 continents. The African Bufos colonized the Old World, and the South Americans colonized the New. As the 2 groups did so, they adapted to different yet similar environments, creating morphological similarities that confused earlier researchers, and which had to be unraveled through DNA analysis.

Bufo’s story within the Americas is pretty cool: all North American Bufo species North of central Mexico appear to be monophyletic, the result of a single migration event. Central Mexico is a barrier for many species, particularly a water-loving amphibian. And even more interesting, though it’s not clear exactly when the earlier Bufo pioneers reached Central America from South America, it appears almost certain that it happened before the 2 were joined via the Great American Interchange*. This is less trivial than it sounds. Toads have water-permeable skins, and are adapted to fresh water**. Sticking most toads in saltwater is a good way to kill them. So continent or island hopping- even via rafting- by a freshwater toad is a pretty tricky undertaking. Whatever the specific details, it appears that not just Red Spotteds, but many of our most common toads in the US, have a fantastic migration history.

*Which I explained in this post.

**The so-called “Salt Toad” of California, which is actually a subspecies of Western Toad, may be an exception. It lives in salty swamps. The Marine Toad, B. marinus, cannot tolerate seawater, despite its name.

We continued down-canyon, each bend revealing a new series of plazas, pools and little waterfalls.

In March 1985, my college roommate* and I flew to Phoenix for Spring Break. IMG_7641 We rented a car**, drove up to the South Rim, and hiked to the bottom of the Grand Canyon. At the time of course I knew next to nothing about the Grand Canyon, or the wider Colorado Plateau in general, but I was blown away by the scale and beauty of the place. In the decades following, I’ve moved out West, spent countless long weekends exploring the Colorado Plateau, often on the fringes of the Grand Canyon, and in the course of doing so learned plenty about the flora, geology, human and natural history of the region. But somehow, even after a quarter century of exploring and dinking around in the backcountry, I’d yet to return to the bottom of the Grand Canyon. So I was really, really looking forward to reaching the river.

*Yup, “Dan” from the Datura post.

**In 1985, an under-25-year-old could still rent a car. And you could reserve a bunk at the Phantom Ranch with about 2 week’s notice.

Tangent: Moments like this lead me to where-does-the-time-go type thoughts. 25 years is a long time, and I never imagined it would take so long to return. It just seems like we never have enough time. In a comment to my last post, KanyonKris mused about the benefits of slowing down the aging process so that we could enjoy more years of old age. But when I think about it, I’m not really sure the long-and-healthy-retirement-dream is the answer*. We already live for several decades- plenty of time to get around to doing, well, everything. I suspect that if we were given another couple of healthy decades, we’d just manage to suck that up with busy-time as well.

*Besides, if we all live healthier and longer, we’re all going to retire later. The demographics won’t support an ever-increasing pool of long-lived geezers retiring in their 60’s.

The irony here is that when you do something really cool, like hike to the bottom of the Grand Canyon, you remember it. I can barely remember what I did a month ago at work. And if you asked me to list things I remembered over the last decade, hardly any of the events or happenings I recalled would be work-related. Remembering stuff is worthwhile; it’s high-value. The stuff of our brains, the material us, is constantly being replaced. There really is no you*. What there is, is the story of you, the storybook you build over your lifetime and carry around in your here-right-now ephemeral head. And that storybook is written from experiences recorded as memories**. If you’re not recording new memories, if you’re not doing stuff worth remembering, then your storybook isn’t being written anymore; it’s just sitting on the shelf, no matter how “busy” and “active” you seem to be…

*I went into this in more detail in this post.

**I went into this in more detail in this post.

Dropping out and being a deadbeat isn’t the answer. Although money doesn’t bring happiness, lack of it, ironically, brings great and consuming unhappiness. The trick is figuring out the balance. That sounds easy, but it’s not, because social interaction, by its very nature, drives us off-balance. We constantly compare our attitudes, values and lifestyles to those of whom we interact with. That’s not a bad thing; we learn and grow from the examples around us, and that interaction can lead us to improve and excel scholastically, professionally, athletically and otherwise. The challenge is structuring our lives so we’re regularly and continually doing stuff in the things-we-remember category and making sure that we’re prioritizing our big high-value goals (hiking down Grand Canyon, learning a foreign language, visiting New Caledonia) alongside our big high-necessity goals (key family relationships, raising offspring, providing for loved ones.)

You can’t do everything. So if you’re going to make the balance work, you have to figure out what you’re not going to do, or spend time and cycles on. I call this Selective Disentanglement (SD), which is probably just a fancy term for “figuring out what I should blow off…” I think I’ve been getting better at SD over the last few years, and over the coming year, I’m going to try and ratchet it up a notch…

A short while later we came to the expected final pour-off, a 40-foot drop we’d need to detour around. Steve, walking ~30 feet ahead of me reached it first. He looked down, raised an arm, and called “Hi!” About a dozen people stood down below looking up, the first “others” we’d seen in a couple of days. They were rafters, hiking up from the river. There was water falling from the pour-off in a little waterfall. In the closed space of the canyon it made quite a little racket, and we had to shout to hear each other. I called down, “How far to the river?”

“200 yards- you’re there!” came the shout back.

Steve and I backed up 30 yards or so and found a place where we could pick our way up, IMG_7661above and around the pour-off on the West side. We traversed a bit further, and then found it- the chute from the guidebook we’d need to down-climb. It wasn’t especially technical (maybe a 5.3?) but it was exposed and far from help. We rigged a hand-line for Steve to descend first, to a ledge ~ 20 feet above the canyon floor. I followed, bringing the line with me to use for the last portion of the descent.

Side Note: If you do this trek and are a risk-averse non-climber, bring 2 ropes and 2 carabiners. There’s a good bolt for each section. The first rope should be 50 feet, the second one 20. If you’re not coming back up, one 100 foot rope (to pull through) will be fine, A hand-line is fine; you don’t need to rappel.

Two of the rafters* backtracked to watch our descent, and gave Steve helpful toehold guidance on the down-climb. When we arrived on the canyon floor they introduced themselves as Lou and David, and offered us food and beer at their camp. Together we picked our way down the last few bends of Tuckup Canyon.

*The rest of the party, which included 2 climbers (they actually own a climbing gym back home in Tennessee) managed to ascend the pour-off and day-hike further up-canyon.

IMG_7660 I asked them how the water was (with a mind to go for a dip…) David replied, “It’s f***ing* muddy!”, and my heart leapt. In the old days, before the dam, the Colorado was pretty much always muddy/silty. But after the dam was built, the river ran with cold green waters from the bottom of Lake Powell, and that’s how I saw it 1985. But the rains of the past week had flushed mud and silt out of the side canyons, filling the river, and making it appear, temporarily at least, like its old self.

*The rafters, with their Tennessee twangs and “colorful” language, were highly entertaining to listen to. The F-word graced every other sentence. Our favorite usage-instance was when one of them, relating a story about a nude sunbather they had encountered earlier in the trip, used it in the middle of the word, “asleep”, as in “a-f***ing-sleep!)

Extra Detail: The post-dam, colder flows have led to significant changes in the canyon. Cold-water trout have replaced native Squawfish and Chub in many places and prey upon their young. At least 3 native fish species have disappeared entirely. The presence of trout in the now-clear waters has attracted Bald Eagles, who first appeared in the canyon in the mid 1980’s. Then there’s the whole beach/shoreline/vegetation thing, but that’s a whole post in and of itself…

IMG_7642 As we walked the last little ways down Tuckup we began to hear a distant “wind” or sound. First a whisper, then building, the road of the river. Around the final bend through the Tapeats slot, the wind was accompanied by a growing light- the bright, wide-open-space daylight of the inner gorge. Steve and I walked faster toward the light and the roar, Lou and David trailing a bit behind us, like modern-day guardian angels.

And then all of a sudden the slot IMG_7648opened up into the inner gorge, and there was light and sky and noise and a highway of roiling, fast-moving water before us, in all of its opaque, muddy glory and power and wonder, backed on the far side by nearly vertical Tapeats cliffs, and finally, 25 years later, I was back.

Geo-Tangent: What I had expected to see, but did not, was one more geologic formation- the Vishnu Schist. Almost 2 billion years ago, in what is now Northern Arizona, a mighty mountain range built up of metamorphic rock. The world was different then; when those mountains began to rise, Earth was fresh from the Oxygen Catastrophe, when recently-evolved cyanobacteria first filled the ancient air with oxygen*, and the ensuing Huronian Glaciation**. A day was only 20 hours long, and a year contained 450 of them.

*Initially the freed oxygen combined with (oxidized) iron. But when no more could be oxidized it began to accumulate in the atmosphere, causing a mass extinction of anaerobic microbial life.

**An earlier, similar, “Snowball Earth”-type event.

Inner Zoom The mountains rose and rose, till they towered high as the Himalayas. Over millions of years following, seas washed over and gradually eroded them down to their base. But the roots still lie there, and elsewhere in the canyon, further East, up around Phantom Ranch, the ancient rock, the Vishnu Schist, is exposed below the Tapeats sandstone, lining the inner gorge.

Extra Detail: Between the Tapeats and Vishnu formations lies the Great Unconformity- hundreds of millions of years of missing rocks that were eroded away prior to the formation of the Tapeats by advancing seas. In some parts of the canyon intervening Pre-Cambrian layers appear- Chuar, Nankoweap and Unkar- and where they do, the Great Unconformity defines the missing layers between them and the Tapeats, while an earlier gap- the Pre-Cambrian Unconformity- defines the missing layers between them and the Vishnu.

But (as I learned later) at the Western end of the Grand Canyon the Vishnu is not exposed, and the Tapeats continues clear down to the river in near-vertical cliffs. The roots of the Old World remained hidden beneath us.

Lou and David produced beers and snacks, which seemed wickedly luxurious in the middle of a backpacking trip. I kicked off my shoes and ran my toes through the warm sand while we IMG_7647chit-chatted about our trips. After a few minutes I got up and wandered barefoot down to the water’s edge. I stood for a moment, taking in the noise, light and tumult of the river, then stripped, waded out hip-deep, and plunged into the silty Colorado.

Note About Sources: As with earlier posts in this series, much of the geologic info came from Bob Ribokas’ Grand Canyon Explorer site, Stephen R. Whitney’s A Field Guide to the Grand Canyon and Wikipedia. Additional geologic and hydrological info for this post came from Volcanic Rocks of the Grand Canyon Area, George Billingsley, Deposition of the Tapeats Sandstone (Cambrian) in Central Arizona, Richard Hereford, and the website of the Natural Arch and Bridge Society. Info on the Red-Spotted and other toads came from David Williams’ A Naturalist’s Guide to Canyon Country, the Arizona-Sonora Desert Museum* website, Thomas Scott’s Concise Encyclopedia Biology, and The History of a Nearctic Colonization: Molecular Phylogenetics and Biogeography of the Nearctic Toads (Bufo), Gregory B. Pauly et al.

*Can you believe I have not been there yet? How is that possible?? Adding to the high-value goal list right now…

Monday, October 25, 2010

Grand Canyon Part 4: Alcoves & Hanging Gardens

From our camp at the junction of Tuckup and IMG_7714Cottonwood Canyons, we day-hiked up Cottonwood one afternoon. The lower part of the canyon involved a bit of scrambling and meandering around and through various jumbles of boulders. There were pools and trickles of water the whole way up. After a while we reached a pour-off with a couple of cottonwoods at the bottom, which we had to leave the canyon bottom to get around. The slope on the Northern side was loose and full of talus; we climbed it one at a time to avoid setting off a rockslide on each other.

Arizona Steve ascended first. As I followed, I could see that the sidehill placed us at the base of a second, higher pour-off that was recessed into an alcove, which Steve had already detoured into. As I paused scanning for a route on up, he called for me to come check it out. The alcove was fronted by a stand of small cottonwoods, behind which lay a pool backed by a wonderful hanging garden.

All About Hanging Gardens

Hanging gardens occur across the Colorado Plateau where continual seeps of water emerge from rock/cliff walls, creating little oases of moisture, and often shade, which support a community of plants quite different from the surrounding desert.

IMG_7717 The reason for these seeps has to do with the hydrology of the rock layers. When you’re traveling across slickrock, it’s easy to see it as dry and waterless. In rainstorms water quickly runs off the rock surfaces (leading to flash flooding). What water does linger pools in pockets and potholes that generally dry up after a time*.

*That time of course varies by the size, depth and aspect of the pocket. Exceptionally large/deep pockets are known as “tanks” and are often year-round effective water sources.

But the rock layers are full of cracks and crevices, and some portion of rainwater trickles down into these IMG_7743hideaways, working its way downwards, leading to the creation of effective reservoirs or even modest aquifers within the rock. Where the crack/crevice network leads to a sidewall or cliff, the waters seep out in tickles or drips. The seep works slowly to weaken and break apart the structure of the wall underneath, causing just to break off and fall away, gradually forming an alcove.

Often this happens when the water encounters less permeable rock below, such as less fragmented/porous rock or a layer of shale, and is forced sideways. In canyon country a likely place for this to happen is at the interface of 2 distinct geologic layers. Further North in Southern Utah, this often happens where the Navajo and Kayenta formations meet. Down here in the Grand Canyon, those younger layers are nowhere to be seen, and so the Cottonwood Canyon alcove-garden, which is also a transition-layer garden, occurs among very different- and older- rock layers.

Water Seep Diagram Extra Detail: Almost all hanging gardens in the Western US occur in/on sedimentary rock layers. And interestingly, some types of sedimentary rock are better “hosts” than others. Specifically layers like the Entrada and Navajo Formations, which have strong cross-bedding, which creates frequent, horizontal layers of increased impermeability, are common host formations. But Wingate- just a little below Navajo- has thinner, less clearly-defined cross-beds, and almost never hosts hanging gardens.

*For non-geology-minded Utah mountain bikers: Navajo is what you’re rolling across on Moab’s Slickrock Trail. Entrada is what you’re “surfing” up at Bartlett Wash. I did a geology-mtn biking post early this down around Gooseberry Mesa, but would love to do a broader mtb-geology post across Southern Utah. We’ll see.

When I learned this, I thought about my absolute favorite hanging garden, at the head of Twin Corral Box Canyon, which I will describe further on down in the post. Twin Corral Box, when you hike into it from the Dirty Devil, is walled with massive Wingate cliffs. But at its upper end, higher up, the cliffs are Navajo. Higher up-stream on the Dirty Devil BTW, the side canyons are overwhelmingly Navajo-walled, and as a result many of them, like the Robber’s Roost system, host wonderful hanging gardens all over the place. (One of the most rewarding things about this whole project has been the numerous ah-ha! moments when something I noticed years ago suddenly makes sense…)

Immediately above the garden is the bottom of the Redwall Formation, which we looked at in the last post. Our hike led us up through the Muav, but in between appeared a narrow and very different layer, which I believe was the Temple Butte Formation (and which I’ll describe later in the post.)

Floor

An alcove-hanging-garden- which is a specific type of hanging garden- supports an array of plants roughly divided into 3 zones. At the bottom of the alcove, by the base of the wall and often alongside a pool, are the most “normal” plants, by which I mean plants that root in soil and grow upwards. The soil is formed very gradually from fragments of the collapsing rock wall. Because the soil is limited and forms so slowly, alcove-gardens are fragile places. If the limited soil gets excessively trampled, peed/pooped in/on or otherwise abused, the plants community in this bottom layer can be disrupted or destroyed. (Exotics- like Tamarisk or Ravenna Grass, Saccharum ravennae, can also mess up this zone.)

Alcove Plant Zones Photo caption Plants here include not just rushes and grasses, but also ferns and alcove-specific species of Columbines, Orchids and Death Camas.

Wall

The middle zone is the “wall” zone, up against the flat, damp, soil-less vertical rock wall of the alcove, and this zone supports mainly algae and cyanobacteria.

Most of the algae species that live on alcove walls are not endemic to that environment, meaning that most occur also in other environments. In a study in the late 1980s roughly 204 species of algae were found on Utah hanging garden walls, out of ~1,900 known statewide*. Of those 204, only 16 were not known to occur in any other environment than hanging gardens.

*I don’t know if this number has increased significantly since then.

chrysophyta But what is different about the algae in hanging gardens is the mix of species. Many are Chrysophytes, Golden Algae (pic right, not mine). The times we’ve looked at algae in this blog, we’ve generally been talking about Green Algae, which are sort of like really, really simple plants- either unicellular or multicellular- that have no specialized or differentiated cells.

Like Green Algae, Golden Algae are generally teeny-tiny photosynthetic creatures, but they’re not at all closely-related to them. In fact they’re likely about as distantly-related to Green Algae as we are. The systematics of these guys are still unsettled (and the group itself appears to be polyphyletic), but it now appears that they belong to a completely separate kingdom, the Chromists, Chromista*, which includes Brown Algae, Yellow-Green Algae and Diatoms, in addition to a few other things you never heard of.

*Way unsettled. In the 2005, an alternative kingdom, Chromolveolata, was proposed, and then in 2008 it was proposed that this group be split into 2 kingdoms. I can’t keep up. In any case, they’re way, way different from Green Algae, and they’re most certainly not plants.

Tangent: This is what is so cool about life at the microscopic level. Up here on the giganto-macro level where we reside, we perceive only a little fraction of the diversity of living things. The “kingdoms” or “kinds of living things that we can see and touch- animals, plants and fungi- appear to be just 3 of 6, 7, or maybe 11(?) kingdoms of eukaryotic creatures. And then of course there are the kazillions of prokaryotes…

Most of the time, most Golden Algae species behave more or less like Green Algae- sitting around, mostly in damp/wet places, and photosynthesizing. But here’s something cool about many of them: when deprived of light, or when they find themselves in the presence of abundant alternative food, they can switch to a predatory mode, feeding upon bacteria and diatoms. Golden Algae are sort of like little alternate-universe plants that can turn suddenly and opportunistically carnivorous.

Alcove Plant Zones Diagram Chrysophytes are common in fresh water, and important in lakes, where they’re believed to be a main source of food for zooplankton. Hanging garden walls seem to be a good environment for them: Roughly half of the 1,900 known algal species in Utah are Golden Algae, but they account for about 70% of the species on hanging garden walls. There’s more happening on those slimy walls than meets the eye.

Ceiling

CTufaBut the most interesting and eye-catching plants occur in the uppermost zone, at the top of the wall or on the “ceiling” of the overhang, rooted directly on or right by the seep itself. Small bits of soil do form and accumulate here, providing nutrients and helping plants to root/attach. But oftentimes the substrate in this uppermost zone is neither bare rock nor soil, but tufa, specifically calcareous tufa. Tufa is a type of porous limestone created by water depositing carbonate minerals. IMG_7723 A very dramatic example of tufa is the huge columns ringing Mono Lake in California. Calcareous tufa, the type found in desert seep-alcoves, is a type of freshwater-deposited tufa with a specific laminate structure and is less porous than most tufa types. Tufa of all types can contain lots of organic matter from debris trapped in its formation. In alcove hanging gardens calcareous tufa often forms a thin, flaking layer on the “ceiling” and sloping upper walls of the alcove.

The common plant at the seep zone is Maidenhair Fern, genus = Adantium. IMG_7724 There are more than 200 species of Adantium ferns* worldwide, many of which have adapted to rock walls, seeps and waterfalls. Our species here on the Colorado Plateau is Adantium capillus-veneris, known alternately as Black Maidenhair or Venus-Hair Fern (pics left and above right). A. capillus-veneris has atypical, sort of “un-ferny”-looking fronds, which look almost like little Gingko leaves. They root well on calcareous tufa, and form thick, lush, bright green, hanging “mats” within the alcoves, decorating the upper walls like draperies.

*I covered the basics of Ferns, and their freaky-cool haploid-diploid generational pattern last year down in Costa Rica. Man, it is like I have a post for everything.

Another seep-zone plant was in flower. When it first caught my eye I thought it some type of Gilia, IMG_7725 but it was actually Scarlet Lobelia, Lobelia cardinalis (pic right*). Lobelia belongs to the Bellflower family, Campanulaceae, and probably the most closely-related thing to it we’ve looked at previously was Harebell last summer up in Glacier NP. Scarlet Lobelia favors moist environments such as stream banks, bogs and meadows in addition to alcoves. Its red, deep and narrow-tubed flowers are pollinated by Ruby-Throated Hummingbirds (like Gila). It was used medicinally by Indians to treat bronchial ailments (including asthma) and supposedly syphilis.

*Sorry- for some reason I only snapped this one rather low-quality shot. I have no excuse except that I take lots of photos when I hike, and don’t really know at the time what- if anything- I’ll blog about.

Tangent: I say “supposedly” because I can’t count how many plants I’ve read about that Indians allegedly used to treat syphilis. Seriously, it has to be dozens. What I wonder is whether any of these plants actually eased the symptoms of the disease (certainly none of them cured it) or whether the Indians were just so desperate that they pretty much tried anything. And in fairness, Syphilis appears to have been a much more virulent (and horrible) disease during its first recorded few decades in Europe than it was by the later 16th century, by which time it was basically the disease it is today.

Syphilis BTW has a fascinating and still unsettled history. For a long time, it was cited as a classic example of a New World disease spreading to the Old World. But other researchers believe that it was already present in both New and Old Worlds. Still other researchers hypothesize that it evolved in the Old World, was carried across the Beringian land-bridge with Paleo-Indians, and then re-encountered by European explorer. The timing of the disease’s history in Europe is tricky; the first major outbreak was in 1494, which would mean that if it was a New World pathogen, it pretty much would have had to arrive in Europe via Columbus’ first voyage.

Nested Tangent: I sometimes pick up a tone of explanation or justification in traditional New-World-Origin accounts of Syphilis. Yes, we gave the Indians Smallpox and a whole bunch of other diseases, the story goes, but hey, they gave us syphilis, as though it somehow balances things out.

Today in the age of AIDS, syphilis is farther down on the list of most folks’ STD-worries, yet another of the multitude of terrible diseases that’s largely been beaten in the First World, allowing so many more of us to live long enough to succumb to cancer. I wonder, if they ever cure cancer, what we will start dying of next?*

*I’m reminded of the old Red Foxx line (paraphrasing): “All these health nuts are going to feel stupid someday, lying in a hospital bed, dying of nothing.”

Scarlet Lobelia’s medicinal properties- whatever they are- likely are a result of the plant’s alkaloids, which can be toxic, and probably shouldn’t be messed with. BTW, you won’t find this flower in hanging gardens up around Moab or Canyonlands; though it’s common in them around the Grand Canyon, Glen Canyon NRA and Zion, it doesn’t appear in hanging gardens further North.

Alcove hanging gardens always seem quiet, contemplative places. When I’m in one I always feel as though I should speak softly and be respectful somehow. I don’t know that this feeling stems from any karmic-greenie Earth-vine or anything, so much as they half-consciously remind me of cathedrals, with their dim light, still, cool air and vaulted ceilings. The Cotton Canyon Alcove is small- maybe 30 feet high, but I’ve stood in others that are huge. The side canyons of the Dirty Devil in particular contain a number of spectacular ones, the largest and most amazing of which lies at the head of Twin Corral Box Canyon, with a ceiling of well over 100 feet high.

IMG_7718 Alcove-gardens are cool, refreshing places offering a break from the sun and heat of the surrounding desert. In the really large ones, the cool, damp air can induce a deep chill within 15 minutes or so, driving you to fumble around in your pack for an extra layer, or retreat back into the sun. Our small alcove was just perfect though, and we found ourselves lingering for a bit. These places have an out-of-time feel to them; it’s easy to be surprised at how much time you’ve dawdled away if you get distracted or don’t keep an eye on your watch.

Tangent: Yes, I backpack with a wristwatch. I do almost everything with a wristwatch. Once on a trip along the Dirty Devil about a decade ago, Steve and I decided we wouldn’t bring a watch. After all, we were backpacking, we had all day, why be constrained by something so civilized as a watch? Why not wake when it gets light and go to sleep when it turns dark? Isn’t that the right, “natural” way to live?

It turned out to be a terrible idea. The trip was in October- a time of shortening days- and we spent most of the trip in deep-walled canyons under overcast skies. We never could never tell what time it was, and as we didn’t want to get stranded out day-hiking away from our base camp after nightfall, we really needed to know what time it was. As a result, we must have asked OCRick- who accompanied us on the trip but abstained form our little back-to-nature-wristwatch-rebellion- the time at least 30 times a day.

Continuing up around and above the alcove was the only tricky part of the hike, involving an exposed scramble up a series of ledges on the North side. Fortunately the rock of these ledges was distinctly different from that below or above- an extremely rough-surface, abrasive stone that was wonderful for free-climbing*. I’m pretty sure this was the Temple Butte Formation, a relatively narrow band between the Muav and the Redwall, that tends to be thicker in the West End of the Grand Canyon**.

TButte Bypass The Temple Butte Formation is interesting in that it appears in channels in the underling Muav layer. The channels may have been streams or estuary channels within with deposits accumulated that became the Temple Butte rock some 350 – 400 million years ago.***

*But would be awful to fall or slide on.

**And which I either missed (entirely possible, as this geology stuff is still pretty new to me) or is absent in the main drainage of Tuckup Canyon.

***Different sources give really different ages for this layer.

IMG_7741 After ascending 2 sets of ledges and crawling between 1 more (pic right), we were atop the alcove* and back in the Redwall, through which we continued up a drainage full of gullies, chutes, pockets, plazas and pour-offs. Every bend revealed some interesting little plaza or pool or minor obstacle (pic below, left)**.

*There’s a bolt at the top of the alcove. Rappelling down would be easier and safer than the ledgy down-climb

**This, BTW, is why hiking narrow canyons is so great to do with kids. The constant surprise-around-every-corner aspect and frequent scrambling opportunities distract them from the mundane-ness of trudging along for hours.

IMG_7730 Eventually we broke out of the Redwall and the canyon, now just a shallow gully on the giant Esplanade terrace lined on either side by low shale hills. A short while later we crossed the Tuckup trail and arrived at the Cottonwood Spring. The Esplanade is dotted with a number of springs like this one. Here the hard capstone creating the terrace* serves at the hydrological barrier forcing the water to the surface.

*Which I described in Part 2 of this series.

IMG_7731 The Spring was marked by a stand of young Cottonwoods (pic right). Standing snags suggested that much larger Cottonwoods used to shade the spot and we wondered why none of the giants still lived. At several point on our hike up we’d come across huge old trunks, even below the alcove, reminders of the force of floods that must scour the canyon.

The ground all around the spring was damp and grassy, and the grass here had a strange appearance, almost hazy, as though you couldn’t focus on it. On closer examination the “haze” was an abundance of super-fine stalks bearing seeds, like nothing I was familiar with.

WPanicgrass caption Back home later I learned this was Western Panicgrass, Dicanthelium acuminatum (pic left, not mine), whichWPG close3 is common across much of the US, but which I’d never before noticed in such concentrations. Panicgrass, BTW, belongs to the same grass sub-family, Panicodeae, as our old friend Crabgrass. While Crabgrass is an Old World native that has become a naturalized pest in the New World, Western Panicgrass is a New World native that has become naturalized pest in the Old.

Tuckup View West from Esplanade Arriving at the spring we suddenly felt beat, and lazed for a while in the shade before heading down. After the Temple Butte down-climb we stopped in at the alcove again to pump some water, then picked our way down-canyon through lengthening shadows back to camp.

Next Up: The River.

Note About Sources: Geologic info for this post came primarily from Bob Ribokas’ Grand Canyon Explorer site, Stephen R. Whitney’s A Field Guide to the Grand Canyon and Wikipedia. Hanging Garden Info came from David Williams’ A Naturalist’s Guide to Canyon Country, and On The Distribution of Utah’s Hanging Gardens, Stanley L. Welsh, from the Great Basin Naturalist*. Welsh’s paper provided the algal species distribution info, but was apparently published before(?) the classification of Chrysophyta as Golden Algae, for which my primary source was the University of California Museum of Paleontology site. Panicgrass info came from the Master’s thesis, A Morphological Invesitagtion of Dicanthelium Section Lanuginosa (Poaceae), Justin Ray Thomas, Miami University.

*Now the Western North American Naturalist. Man, there is like a publication for everything.

Wednesday, October 20, 2010

Grand Canyon Part 3: High Times

IMG_7535As the canyon walls rose, the floor of Tuckup became more shaded, and greener, bigger plants began to appear. Oaks soon reappeared alongside the wash, but now they were Shrub Live Oak, Quercus turbinella, bearing tough, persistent, holly-like leaves, and growing into small trees. Soon another tree appeared, one that I didn’t recognize, with roundish leaves, but the pea-like seed pods (pic left) told me it was part of the Pea family, Fabaceae. It’s Western Redbud, Cercis occidentalis, which is widespread in California, but has only a IMG_7542limited and disjoint range in Southern Utah and Northern Arizona. Indians of California traditionally used the flexible twigs of this shree to weave baskets, and derived a red dye from its bark. Photos of the flowers look stunning; I’d like to see it in bloom sometime.

Side Note: It’s funny, when I posted about Pea family trees down in Mexico last Spring I mused about how relatively uncommon they seemed to be closer to home. Since then I’ve encountered 2 “new” trees, Western Redbud and New Mexican Locust, both in or by the Grand Canyon, both members of the Pea family.

IMG_7694 As the canyon grew deeper, the sandy, gravelly floor grew damper, and we kept an eye out for waterpockets. Leafier things began to appear, some- surprisingly- still blooming in October, such as Hooker’s Evening Primrose (pic right). Finally real water pockets and dripping springs started to pop up, the result of the recent rains, and not long after we came to a series of pockets that looked slightly more permanent, as evidenced by the Cattails growing out of them.

I’ve seen Common Cattail, Typha latifolia, thousands of times, all over North America, but don’t ever think I’d ever before chanced upon them releasing their seeds to the breeze, as these were Thursday afternoon.

Cattails have been around for a long time, and are obviously related to grasses, with which they parted ways over 100 million years ago. Unlike grasses, they never adapted to semi-arid conditions, and are always found in or by water. You might guess that they’re close cousins of Rushes or Sedges, but they’re actually more closely-related to Bromeliads, which we looked at last year down in Costa Rica.* Cattails are Wind-Wind, as in wind-pollinated with (obviously) wind-dispersed seeds and are monoecious (same plant bearing both male and female flowers) but also spread by rhizomes (root-cloning) with dense stands aggressively crowding other plants out of waterpockets and mudholes. Later in the trip we’d come across depressions in expanses of open slickrock in which enough soil and water had accumulated to support such stands.

*Man, it is like I have a post for everything.

But there was one recurring shrub- IMG_7531more of a ground-cover really (pic left)- growing in the sandy canyon bottom that I didn’t recognize. Its broad, pointed leaves were slightly asymmetrical, in that the base of one side was anchored to the stem slightly lower than the other. On many of the plants, spiky green racquetball-sized “fruit” appeared, in some cases dried, browned and split open, revealing a multitude of little seeds inside. Finally we stumbled across a blooming patch, and our mystery canyon ground-cover revealed herself in all her Georgia O’Keefe splendor as Sacred Datura, Datura wrightii.

IMG_7571 There are ~9 species of Datura across Eurasia and North America. The common species on the East Coast is Datura stramonium, commonly known as Jimsonweed. D. wrightii is restricted to the Western US and Mexico, though its range has been extended both as a weed and ornamental.

Datura belongs to Solanaceae, the Potato family, which includes, in addition to Potatoes (200+ wild species!), Belladonna, Chilis, Tomato, Eggplant and Tobacco. Solanaceae members typically share a diploid chromosome count of 24* (n=12) but the more relevant common characteristic is the presence of a series of alkaloids known as the tropane** alkaloids, a number of which have notable and powerful effects on the human body.

*The common Potato you buy at the supermarket, Solanum tuberosum, is tetraploid, with 48 chromosomes, but wild potatoes can be diploid, triploid, tetraploid, pentaploid or even hexaploid. Still others are diploid, but with a haploid number of 13 (n=13), so they have 26 chromosomes.

**Derived from Atropa, the genus of Belladonna.

Flower Fruit The classic example of a tropane alkaloid is of course nicotine. Another, more benign* example with which you’re certainly familiar is capsaicin, the “burning” ingredient in chili peppers.

*Well, usually benign. It’s also the active ingredient in pepper spray. BTW, here’s a fascinating little nugget I stumbled across in researching this post: birds are immune to capsaicin. So if you get attacked by a wild ostrich and all you have for defense is a can of pepper spray, man you are SOL.

Sacred Datura, like Jimsonweed, has long been IMG_7532known for its hallucinogenic effects, which are caused by- you guessed it- tropane alkaloids. Later in the trip, I’d learn a bit about the pharmacological effects of Datura from Guardian Angel Lou (whom we will meet in the final installment of this series) and- just in case- pocketed* one of the “thorn-apples” on the hike back out to facilitate any possible “experiments”. After returning home and researching the heck out of this plant, I will never, ever screw with it.

*Figuratively. I actually very carefully wrapped it in plastic and placed it in my pack. Handling these things is tricky.

Tangent: And yes, before I knew more about it, I did flirt with the idea of experimenting with it. Though I experimented with marijuana in college, I never tried any kind of hallucinogen, and although I have no desire to suddenly become a middle-aged druggie, it’s one of those Life Experiences I mildly regret having missed out on.

Nested Tangent: “Experiment”? Did I actually say “experiment”? Oh for crying out loud- I smoked it, OK? I smoked it and enjoyed it, like every college student alive in the 1980s who wasn’t ROTC or attended Oral Roberts University or BYU. And what’s more, I’d probably smoke it again today, if… I hung out with people who had any. Seriously, I almost never encounter it in my social circles, and though smoking dope was fun, it was never so fun that I’d actually go out of my way to seek it out. For me marijuana was kind of like the TV show Ugly Betty is for me today. When I come across it I watch it and generally enjoy it*, but not so much that I try to record it or figure out when it’s on next or anything. Anyway, that’s how I feel about pot. (Though if I lived in California, I’d vote for Prop 19.)

*Although this may be because I’ve always kind of had a thing for Vanessa Williams. OK so I guess I’d pick watching Ugly Betty over smoking reefer. Unfortunately I checked for this post and found out the series ended this Spring. Guess I should have tuned in more often.

But for a moment I succumbed to the politically-correct moniker of “experiment”. What’s up with that? We don’t say we “experimented” with skydiving or witchcraft*. But there’s like this limited range of human vices for which we somehow try to excuse ourselves for having partaken in by calling them “experiments.” It’s like we amble along, living our day-to-day, regular-joe lives, but when it comes to drugs or illicit sex, suddenly everyone’s like this Big-Time Scientist, you know, not actually enjoying it or anything, but “experimenting” for the sake of scientific enlightenment or whatever…

*We use “dabble” for that one…

Most of my college-era maryjane experimentation was conducted in the company of my college roommate- let’s call him “Dan”- who enjoyed the stuff just slightly more than I did, as evidenced by his actually getting a hold of some, which I could never be bothered to do.

All About Hallucinogenic Drugs

There are 3 main types of hallucinogens. Psychadelics, which include LSD mescaline, and peyote are what most people think of when they think “hallucinogenic drug.” These drugs alter the perception of received sensory inputs- visual, audio or otherwise. The second category are disassociatives, which include things like PCP and the plant Salvia dinorum. These drugs act to partially or fully block the input of one or more senses.

Datura belongs to the 3rd type, called deliriants, or anticholinergics, IMG_7575which act by blocking acetylcholine, one of a number of neurotransmitters* controlling many subconscious functions, and the primary (only?) neurotransmitter controlling voluntary muscle function outside of the brain and spinal chord. Deliriants are sometimes called “true hallucinogens” in that they can lead to complete, realistic full-on hallucinations (i.e. conversation with an imaginary person) as opposed to the “modified-reality” type hallucinations induced by psychedelics. Deliriants have generally been the least recreationally popular of the 3 types due to their many negative side effects.

*I talked about neurotransmitters in this post, though I didn’t cover acetylcholine.

The specific alkaloids at work in D. wrightii are atropine, scopolamine and hydrocyamine. Scopolamine you’re probably already familiar with; it’s the stuff the eye doctor drops in your eyes to dilate your pupils, and unsurprisingly, Datura has notable effects on vision.

IMG_7568 Many, many instances of Datura use have lead to hospitalization or even death. In one scenario, the delirium sets off a panic which is exacerbated by partial or complete vision loss*, leading to injury through the ensuing, very literal, blind panic. Other negative effects can include bizarre or violent behavior, prolonged aversion to bright light, hypertension, amnesia and fever of up to 110F.

*Even following a “positive” use experience, at least one user reported difficulty reading for nearly 2 weeks following.

One of the most dangerous aspects of Datura is the range of toxicity among individual plants, the concentrations of toxicity in various parts of the plant and even the range of toxicity in the same plant, in the same parts, at different times, resulting in toxicity typically ranging by a factor of five.

So why try it? When it does work, and doesn’t put you in the hospital or kill you, IMG_7572it supposedly produces some unique effects, particularly some visually. People, and other living things are reported to appear enhanced, or clearer visually, with almost a “glow” about them in some cases. The visual difference between living and non-living things is allegedly stronger than with “straight” vision. And conversely, manmade things- structures, power lines, etc.- are reported to seem much uglier than normally.

The “classic” mode of preparation is to brew a tea from the seeds. Unfortunately this seems to be the method likeliest to put you in the hospital (or the morgue.) The most common alternate method is to brew a tea from the roots, but supposedly this is so mild as to produce no effect at all. An alternative, (claimed) middle-of-the-road approach is to smoke the flowers, releasing the alkaloids from the pollen. Allegedly, the sweeter-smelling the flower (vaguely of jasmine) the readier it is to be smoked.

It’s unlikely at this stage of my life that I’ll ever getIMG_7569 around to trying an honest-to-goodness hallucinogen. Responsibilities, fatherhood and the general risk-aversion that comes with middle age conspire to discourage me from ingesting any new potent chemical agents. But I’ll always wonder about the experience of chemical hallucinogens/ deleriants. The brain is complex hodgepodge of chemical circuitry. If an agent somehow altered- temporarily, safely- some aspect of that circuitry, could we sense, see or know things we couldn’t know otherwise?

Tangent: Maybe, though I suspect not. When “Dan” and I smoked pot, we used to have all these Amazing Incredible Ideas, which we were sure would Fundamentally Change The World, if only… if only… if only we could remember them the next morning. So one time we got high with pen and paper in hand and wrote down several of our Amazing Incredible Ideas, which in the light of the following day turned out largely to be alternate ways to order pizza or prepare ramen noodles.

Nested Tangent: “Dan” also once surreptitiously tape-recorded us, in hopes of accomplishing the same. Of course no big ideas were captured, but the resulting tape was incredibly funny*, and we listened to it many, many times. “Dan” entitled the cassette case, “We’re Really High” and kept it on his shelf of cassettes alongside tapes of Pink Floyd, The Who, etc. Sadly, “Dan”- always braver in word than in deed- later destroyed the tape, afraid that his mother would come across it in the course of one of his dorm-related moves.

*After 30 minutes or so of free-ranging dialogue, the tape ran out to the sound of- I am not making this up- my snoring.

Arizona Steve and I continued down-canyon until we reached the IMG_7547 junction with Cottonwood Canyon, joining from the West. Shortly before the junction we passed the bottom of the Redwall Formation and entered the Muav Limestone, another sea-bottom-deposit layer, but further off-shore, laid down some ~515 million years ago. Muav tends toward a grayish color, whitened where its been smoothed over by water flows. The band of Muav is much thicker/deeper toward the Western end of the Grand Canyon (where we were) than in the Eastern reaches. At the junction were several pools full of crystal-clear water, one trickling into the next through smooth shallow grooves in the white stone. We pumped water, ate and rolled out our bags on narrow ledges above the pools, watching shooting stars until we were lulled to sleep by the soft trickle of the water.

Note About Sources: Western Redbud range info came from the USDA’s Natural Resources Conservation Service site. Cattail info came from David Williams’ A Naturalist’s Guide to Canyon Country and Wikipedia. Much of the basic info around anticholinergics came from Wikipedia, but far and away the most informative and fascinating source for this post was this post/article on the absolutely fascinating and well-written (if somewhat unconventional) blog/webzine Luminous Numinous.