Wednesday, July 31, 2013

Grassland, Forest and an Igneous Intrusion

Devils Tower -- a puzzling igneous intrusion in northeast Wyoming.
Recently I spent a day wandering around Devils Tower looking for just the right shot.  It had to feature mixed-grass prairie and ponderosa pine forest, with Devils Tower in the background.
Replacement needed, in full color (from Knight 1994).
I was sent on this mission by Dennis Knight, Professor Emeritus of Botany at the University of Wyoming, who is revising his 1994 book, Mountains and Plains -- the Ecology of Wyoming Landscapes.  How fitting! ... it was an encounter with Dennis at Devils Tower that led to my enrollment as a Botany grad student at the University.  He was in the audience at an evening campfire program, and afterwards explained he had enjoyed my discussion of vegetation and bedrock.  The rest is history, as they say, and now 35 years later we’re back on the same topic.

At Devils Tower National Monument, ponderosa pine forest is best developed on sandstone ridges, and on buried talus around the base of the Tower.  With deeper roots, pines can tap into accumulated water among buried rocks or in fractures.
Grassland - pine forest mosaics are common in the northwest Black Hills.
Shallow-rooted grasses do well on fine soils that hold water close to the surface, for example soils derived from Permo-Triassic Spearfish red beds and shaley members of the Jurassic Sundance Formation.

What a nice orderly arrangement -- grasslands on fine soils, pines on buried talus and sandstone ridges.  Our pattern-seeking minds love such things!
From ArcGIS online; click on photo for details.
The Black Hills were named for the ponderosa pine forests that make them appear dark against the surrounding plains (below, from Google Earth).  Elevations are lower than in other mountain ranges in the region, and the relatively fast-growing ponderosas are the basis for a timber industry that costs tax-payers little or nothing (usually we subsidize timber harvest on public lands in our region).
But the Black Hills are not entirely forested.  Mixed-grass prairies are common.  These are indeed mixes -- of tall-grass prairie and short-grass prairie species.
From Regional Trends of Biological Resources  (USGS); mixed-grass prairie zone in purple.
The photo above currently is the front-runner for Dennis’s book.  The grassland on Joyner Ridge is an excellent example of mixed-grass prairie, with the following grasses common:
tall-grass species:  big bluestem, green needlegrass, needle-and-thread
short-grass species:  blue grama, buffalo grass
I especially like this shot because of the yellow coneflowers (Ratibida columnifera) in the foreground -- they’re classic prairie wildflowers.  But it will be Yale University Press that decides if the photo is appropriate.
Hiking trails at Devils Tower (NPS); click on photo to enlarge.
You can tour the vegetation of Devils Tower National Monument via hiking trails.  The Tower Trail goes through pine forest on buried and partially-buried talus.  There’s also an interesting rock to check out along the way.
Needle-and-thread grass on Joyner Ridge.
The Joyner Ridge Trail passes through mixed-grass prairie with great views of the Tower, and draws with oak, ash, chokecherry, wild plum and other hardwoods.  A connector trail hooks up with the Red Beds Trail through badlands of the Spearfish Formation.  From there, you can head down to Dog Town, where prairie dogs serenade you as you wander through the amazing diversity of plants they manage, both native and non-native.
Dog Town -- a highly-managed landscape.
Two of the managers.
I used to live within view of Devils Tower, and have spent a lot of time there in the years since.  Even so, I think it will always look improbable and mysterious to me.

Sunday, July 28, 2013

Signs -- context is everything

The National Park Service awarded me the highest rating, A1, for my work at Devils Tower National Monument.  Congratulations to self!

Well, actually ...
... it was my campsite, Site 1 in Loop A.

The sign above had a lot more impact when it was on the summit of Devils Tower.  I bet no one disobeyed!
Devils Tower in northeast Wyoming, a rock climber's paradise.
Unfortunately, someone took the Chief Ranger climbing less than a week after we put it there.  Now it's back at the top of the talus slope, where it's often ignored.

☞   ☜
These signs are my meager contribution of detritus for Accretionary Wedge #58 -- Signs!, kindly hosted by Evelyn Mervine.  With free time so scarce these days, I considered sitting it out ... but tectonic forces are hard to resist!

Sign?  What sign?
Ignorance is bliss.  Sparky the Geo-Dog enjoys freshly-exposed red beds.

Friday, July 12, 2013

Plants and Rocks v. 1.2

Laramie columbine on Laramie granite.
It was two years ago this month that I started In the Company of Plants and Rocks.  The plan was to write about work and research, but I soon lost interest and blogging came to a halt.  Then a fall hike in the Medicine Bow Mountains in search of stromatolites opened my eyes to the excitement of nature blogging, and I was hooked.

I’ve long intended to upgrade various blog features, but always ended up writing posts instead.  Now Version 1.2 finally has been released.  Here’s what’s new:

Expanded profile in the form of an About page  [Did you know you can't add a Pages gadget with Add Gadget?  See this helpful video.]

• New camera -- until recently, all photos were taken with a Canon Powershot A720 IS.  Now I also use a Canon Rebel T3i with the stock EFS 18-135 mm IS lens and a Canon EF 100mm f/2.8L Macro IS USM.

• Improved tag cloud -- pared down and organized, a work in progress

• Google+ membership and Twitter account (@plantsandrocks)
Now it’s time for a brief sabbatical until a field project and overdue paper are done.  Of course a few photos will show up occasionally, and perhaps a geo-challenge.  If you need a Plants-and-Rocks fix in the interim, here are some of my favorite posts (also among the more popular).

Happy Birthday John Muir ... poetico-trampo-geologist-botanist  My mentor would have been a blogger if he were alive today, I'm sure of it ... just read his words!

The largest erg on earth ... ever! is now the wonderful Navajo sandstone, my favorite formation to camp in.

Plants & Rocks: ferns and granite ... and climbers...   A tribute to fern lovers and great pioneers of rock climbing, Herb and Jan Conn. 

Field Injuries (Accretionary Wedge #55)  I myself have not suffered any real injuries doing field work, but my poor Volkswagon did ... repeatedly.

Insights from the Other Side of Yesterday Can legend inform geology?  In the case of the volcano Pinatubo, yes.

There's a hole in the ground (geology is destiny) I drove by the Vore Buffalo Jump many many times without stopping until the idea of a blog post finally made it happen.

“a great rectangular obelisk” and The many views of Devils Tower recount the many stories that try to explain this puzzling monolith.

Poems for the Inexplicable  I will always love the rugged Central California Coast as well as Robinson Jeffers' poetry about it.

but there s life in the old dame yet, the old dames being ancient bristlecone pines in the spectacular White Mountains of eastern California.

What’s an old oak for?  More California treasures ... the live oaks of the coastal mountains.
Photo by Giovanni LoCascio.
Still Life with Pebbles  Why is it in our nature to comb the beach for just the right rock?

We too are ephemeral ... just like mountains.  The Cutler Formation of Fisher Valley, Utah, was my introduction to the Ancestral Rockies.  These mountains are long gone, though their remains are still with us (more pebbles). 

Jack Frost’s Latest Artwork, a tour of hoarfrost on the river, and the first of many posts about winter ice art.

What fruit is this? tomato? tomahto? ... maybe love apple!

Will the real Yam please stand up ... Have you ever wonder why our yams and sweet potatoes are so similar?  Well, they're both not yams ...

Trip Plans: the amazing Expanding Great Basin!  that's what it is, for sure!

A Novel Discovery by an Accidental Botanist (a letter to the Earth), a "first-hand" account of the discovery of the Laramie columbine (photo at top of post) by the young botanist who would go on to become Father of Wyoming Botany.
Aven Nelson in the field.

Friday, July 5, 2013

Fresh Petals for Breakfast

After an early-morning safari shooting yucca flowers, breakfast is ready.
Not far from town is a thick stand of Great Plains yuccas, growing on sandy soil as they like to do.  They’ve been blooming copiously for several weeks, and it certainly looks like a bumper crop this year ... once again.  The stalks heavily-laden with large flowers always give that impression.
Yucca petals are edible, and while I don’t find usually find wild harvest to be worth the time and effort (except for berries), I often eat petals when I walk though a yucca patch.  They have a nice crunch to them, a mild appealing taste, and are large and easily plucked.
I’m not the only creature that finds yucca petals tasty.
Even so, I wouldn’t rely on yucca flowers for a meal, and in truth, there was a more important reason for the expedition.  It was a calm morning with barely a breeze, and the large heavy yucca flowers were perfectly still ... just the right conditions to try out my new macro lens.
I’m finding macro photography to be a work-in-progress and very much a learning experience.  It seems experiment and trial-and-error are just as necessary as research.  So far, the challenge and occasional pleasing results have compensated for frustration.

Outside with enough light, the Canon EF 100mm f/2.8L Macro IS USM on a Canon Rebel T3i seems to function well hand-held.  Per many recommendations, I set the camera to aperture priority (Av) to control depth of field.
From Focusing Basics at Exposure Guide, a very helpful site.
Shallow depth-of-field blurs the background, making this ladybug the star of the shot.  I wish I had moved the leaf in front out of the way ... live and learn.
Below is a look inside a yucca flower.  Note the darker green stigma, the receptive female organ where pollen is deposited for fertilization.  It sits atop the three-lobed ovary with ovules (future seeds), and is surrounded by curious club-shaped stamens.  These are the male pollen-producers, but their moment in the sun is over -- the anthers have shriveled or fallen off (yellowish spots at tips).
There are ca 50 species of yucca, all native to North America.  Great Plains yucca is the most northerly, growing into southern Alberta.
The hardy Great Plains yucca, Yucca glauca, has no problem with Wyoming winters.
Almost all yuccas are pollinated by a specific kind of moth, though whether they are strictly dependent on their particular moths is still debated.  The yucca pollination system is a classic and oft-cited example of plant-pollinator interdependency and coevolution.  Without yucca moths, yuccas can’t reproduce, nor can yucca moths reproduce without yuccas.  But together, love works for all.
Yucca moth in a Great Plains yucca flower.  Source: USDA Forest Service.
The life of a yucca moth is short, focused entirely on reproduction.  Males and females emerge from cocoons at the same time that their yuccas bloom.  They flutter about, somehow arriving on schedule for a tryst among the petals.  The male’s mission is thus accomplished, but for the female, there still is much to do.  She collects pollen from the flower’s anthers, balls it up under her chin, and flies off to a different plant to lay eggs, doing the yucca a favor by ensuring out-crossing.  When she finds a flower with no other moth eggs, she lays some (but not too many) eggs in the ovary, and then proceeds to do the necessary pollinating, placing a bit of her pollen load on the stigma.  Pollination leads to fertilization and seed set, so her offspring will have something to eat when they hatch.  It’s impressive how closely coordinated plant and pollinator behavior are, and just how well everything works.  It’s especially wonderful that we have figured out enough to be able to enjoy the story ourselves.
Some of the yuccas have beautiful bicolored flowers.
A look inside a flower -- six stamens surround the three-lobed stigma and ovary.
Back at home, I took the next step.  I put the camera on a borrowed tripod for even closer shots, but in spite of additional equipment, the results generally were not impressive.  Perhaps insufficient lighting was a problem, or figuring out what to focus on for a given aperture (depth-of-field).

There was occasional success ... I like this accidental curious shot.

Yucca flower with scale, for the more scientifically-minded.
Another peek into a flower ... not nearly as nice as those taken outside in natural light.
The flower below has not yet been visited by moths -- note the anthers are unopened.  Sharper focus would have been nice.
In spite of limited success, I learned some neat things about my camera and lens, for example Live View mode (monitoring everything with the LCD panel) and using manual focus to refine auto focus.  Fortunately, at this point the path is as intriguing as the destination.
Fun with gear.

Sources (in addition to links in post)

Yuccas and yucca moths

Pellmyr, O.  2003.  Yuccas, yucca moths, and coevolution: a review.  Ann. Missouri Botanical Garden 90:35-55

Sheppard, C.A. and Oliver, R.A.  2004.  Yucca moths and yucca plants: discovery of “the Most Wonderful Case of Fertilisation”.   American Entomologist 50:32-46.  PDF

Macro photography

from Cambridge in Color

from Exposure Guide

from Kew Gardens

Monday, July 1, 2013

Recommended field apps for iPad mini?

Field work starts in a few weeks.  Since last season, I’ve acquired an iPad mini with GPS/data capabilities.  I'm hoping to find a GPS app that will allow me to take photos and enter notes when marking waypoints.  There must be some ... do you know of any?  If so, please let me know which you like via Comments below, or by email (hollis dot marriott at gmail).  Thanks!
My new toy tool.
My first project is at Devils Tower National Monument in the Black Hills in northeast Wyoming, finishing up a plant inventory started last year.  The Tower is the most amazing rock I’ve ever seen, even after ca 50 years of looking!  El Capitán in Yosemite Valley comes close, but it’s part of a landscape of similar features.  Not so Devils Tower.  It stands alone -- a beautiful and puzzling igneous intrusion in an otherwise sedimentary setting, the valley of the Belle Fourche River.
"The Devil's Tower on the Belle Fourche in northern Wyoming."  By Thomas Moran, 1894.

For more information about Devils Tower, see last year's posts