Tuesday, May 18, 2010

The Toads of Mount St. Helens

Today being the 30th anniversary of the eruption of Mount St. Helens, I wanted to describe a visit I made to the mountain several years ago. I was out in the field with Charlie Crisafulli, a researcher for the U.S. Forest Service. We were heading to small lake about eight miles north of the crater when Charlie told me “Be careful where you step as we approach the lake.”

At first I didn’t understand why he warned me; the terrain was level and we were walking on a four foot wide path. As we got closer, though, the ground began to move. Dark, half-inch-long toadlets hopped everywhere. Scores crossed the path. More moved along the sides and others disappeared into the dense green understory. At the lake, we found thousands in pulsating piles collected along the water’s edge.

When I looked closely, I saw that many of the little hoppers had yet to loose their tails. Charlie, who had been studying the mountain since the eruption, explained to me that they were recently metamorphosed boreal toads and that they soon would head up into the hillsides that surround the lake and continue one of the most amazing stories at the volcano.

During Charlie’s first ten years on the mountain, he had noticed large numbers of boreal toads. This surprised him because the toads, warty, four to five-inch long, brownish green hoppers, had been on the decline throughout the west. (They are listed as “endangered” in Colorado and New Mexico and designated as a protected non-game species in Wyoming.) Trying to determine why the toads thrived at the volcano, he surveyed every lake in the national monument in the early 1990s and found that four lakes had far and away the areas of highest toad density.

In an ongoing study of the one lake where we had tiptoed through the toads, Charlie discovered why so many toads now lived at the volcano. Each June, he and his crew hike out to the partially frozen lake, where hundreds of toads and a handful of northwest salamanders hop and crawl across the snow. The researchers then wade into the water, push aside rafts of ice, and wait. Males arrive first. After the females arrive, pairs mate quietly (the male lacks the typical toad mating call), and produce teeming masses of eggs, up to 12,000 per female. Eggs hatch 7 to 10 days later. The toads we saw had recently crawled out of the water and were preparing to disperse into the mountains surrounding the lake.

“We think that this is what happened in 1980. During the eruption, the frogs were hibernating underground and emerged a month or so later and continued their normal life cycle,” said Charlie. In the long term, the toads benefited because the eruption blasted down all of the trees around the lake, making the water warmer thus increasing food resources during the summer and allowing tadpoles to mature more quickly. The blast also removed most of the toads’ predators, so more toadlets and adults survived.

Thirty years later, the toads are still thriving at Mount St. Helens. In doing so, they have contributed to a new understanding of ecological recovery. In landscapes where geologic and ecologic change is the rule and not the exception, disturbance plays an important role in the life of the ecosystem. Fires, volcanic eruptions, and floods regularly reshape broad swaths of the American West. Sometimes, entire ecosystems are devastated. But every time a cataclysm happens, the plants and animals recover.

It’s a lesson, perhaps, in patience: What we see today as a natural disaster may not be a disaster at all, just a natural clock resetting, a cycle starting over again. Lessons come in all shapes, sometimes even little green ones.

Friday, May 14, 2010

Giro d'Italia and Carrara

In honor of the Giro d'Italia ending in Carrara today, here's a take on the town. I first saw Carrara and its quarries from a car window, while I was driving north out of Pisa. My wife, a couple friends, and I had stopped in Pisa to look at the Leaning Tower but left after about 45 minutes. It’s not made of Carrara marble and the commercialization was offputting. I didn’t need to buy boxers with Leaning Tower located in a prominent place.

We were about 25 miles or so from the green foothills of the Apuan Alps. Broken clouds created a pattern of shade and light punctuated by several bright white splotches. Earlier I had read guidebooks that explained that “No, that isn’t snow, it’s marble,” so I knew I was seeing the Carrara marble. I was quite giddy at seeing it, but as we drove closer to town my excitement began to fizzle. Where were the charming old buildings? Quarries had been worked in these mountains more or less continuously for the past five centuries and I expected quaint structures made of the local stone. Instead, the road felt like many other industrial/shopping mall districts I had driven by, with warehouses, car dealers, and restaurants creating a monotonous blur of banal buildings. I enjoyed seeing all of the stone mills, each with stacks of marble blocks, pallets of sliced stone slabs, and massive cranes for ferrying the stone, but they looked like any stone mill I had seen in my previous travels.

Finally, as we drove closer to the mountains the wide, industrial street gave way to a confusing maze of narrow, often one-way, poorly marked roads. After circling around, getting lost, backtracking, and hoping we knew where we were, we crammed our little rental car into a spot along a lane about twice as wide as our car. A typical Carrarese building, a four story, plain stucco-covered structure, stood about two feet from my front door. On the other side of the road, and twenty feet below us in a concrete-sided trench, ran the Torrente Carrione, Carrara’s couple-inch-deep trickle of a stream.

Abandoning the car, the four of us wandered toward where we thought our bed and breakfast might be. The streets closed tighter, eventually getting too narrow for cars. Above us rose canyon-creating buildings, many with windows festooned with drying laundry and hanging planters. Not every building was made from marble, but I had no doubt we had entered a hub of the marble universe. Not that the locals respected their great stone; graffiti covered many marble walls and several marble statues.

The next morning, I met with Dr. Paolo Conti, a geologist at the Center for Geotechnology at the University of Siena. Paolo had graciously offered to take me up into the mountains to learn more about the quarries and the geology. Getting in his car we drove three miles or so into the Apuans. We parked in a lot next to the Ponti di Vara, a handsome, five-arched, brick-and-marble bridge. Originally, a route for the railroad that crisscrossed the quarries, the Ponti di Vara is barely wide enough for the hundreds of trucks that zip across it each day.

From where we stood, we could look directly up toward the quarries of marble. They glowed a blinding white in the sunlight and had crept half way up Mount Maggiore, which rose 3,000 feet above us. Across the road, yellow signs pointed to several quarries, including the legendary Fantiscritti, quarried since Roman times. Another sign read “Visita la cava in galleria piu’ bella del mondo.” Visit the most beautiful underground quarry in the world.

Pulling out several, very cool and colorful geology maps, Paolo showed us that we were at the base of the Miseglia valley, one of three quarry valleys around Carrara. To the north lay Torano and to the south Colonnata. Each cut back into the Apuans for several miles and each had quarries first operated in Roman times. No one knows how many quarries have pierced these mountains but I have read an estimate as high as 650. One of Paolo’s geologic map from 2000 listed 187 quarries.

Since I wanted to see more of the quarries, Paolo suggested we head up above the next valley north, Torano. After driving for ten minutes or so, Paolo swerved the car across the road on a hairpin turn, and pulled off on a very soft shoulder. His driving seemed like a typical geologist’s, veering abruptly to see rocks, combined with an Italian’s sanguinity at cutting across a blind turn.

“I often bring students here,” said Paolo, perhaps explaining his driving calm. “It’s one of the better spots to see the thick beds of limestone (the 200-million-year old source material for the marble).” We got out, I looked both ways, and crossed the road. Oaks and beeches, some of which had begun to change color, grew out of the gray, massive rock. I had encountered limestone like this before in many places. I called it tearpants limestone, in reference to its sharp, resistant edges. “We haven’t found many fossils in this rock but this is one place we have,” said Paolo. I looked but found nothing other than a few snails crawling across the broken edges of lackluster limestone.

Up and up we drove as the road climbed and wound steadily through the foothills. We passed through zones of pines, under a canopy of rust colored beeches, before stopping near a small lodge, where we hoped to find lunch. Since it was closed we walked across the road and hiked up a trail to the Refugio Carrara, one of the elaborate huts that one can stay at throughout the Italian Alps. We did find lunch there and I got to accomplish one of my goals for the trip.

Over the past few years, a cured pig fat called Lardo di Colonnata has achieved a certain status among epicures, but for Carrara’s cavatori lardo has been a staple of their diet for centuries, a cheap, abundant food that tasted cool and refreshing on a hot day. I knew I couldn’t quarry stone, but at least I could eat like a quarryman. The Carrarese make lardo in their dank basements by curing raw pig fat in a tub of marble. Additional flavor comes from a combination of rock salt, pepper, garlic, and rosemary. Like the cavatori, I ate my thin slice of lardo with onion and tomato on bread. It had a creamy, translucent texture and melted deliciously in my mouth. I followed it with a shot of espresso. Geologizing doesn’t get any better than this.

Energized by pig fat and caffeine, we headed back out to find rocks. Paolo whisked us down the road to a spectacular viewpoint into the Torano Basin, where I could finally get a sense of the scale of quarrying. In the center of the valley, fifteen hundred feet lower and a three quarters of mile away, a ledgy quarry, known as Polvaccio, stairstepped up the valley face. Polvaccio has been worked since Roman times and was where Michelangelo quarried his Pietá block. Getting out my binoculars, I counted 18 ledges of marble, each of which Paolo explained was between 15 and 30 feet thick.

Nearly every inch of the valley walls around Polvaccio had been ravaged by quarries. Road after road zigzagged up the nearly vertical faces, faces covered white in marble by years of quarry debris. The bends on the quarry roads are so sharp that trucks cannot turn and instead back down every other switchback. More roads climbed the valley wall below me, as well as the smaller valleys south and east of Polvaccio. At the high points of the southern and eastern valley ridgelines, quarries had lopped off the summits, creating openings shaped like gun sights. “I remember when there was a mountain there,” said Paolo. The view was one of the most spectacular and disturbing I have ever seen.

Tuesday, May 4, 2010

Greystones: Chicago's Answer to Brownstones

Many people, including me, have written extensively about the classic brownstones of New York and Boston. Recently, I learned about a similar building style popular only in Chicago. Architects and historians call the buildings greystones. The term refers to structures built primarily between 1890 and 1915 and most often in the Chicago neighborhood of North Lawndale. A survey published in December 2005 for the Historic Chicago Greystone Initiative estimated 1,714 greystone buildings in North Lawndale.

North Lawndale has an incredibly rich social history. By 1930, only Warsaw and New York had more Jewish residents. Forty nine synagogues dotted the neighborhood. By 1960, however, African-Americans made up 91 percent of the population. As Charles Leeks of Neighborhood Housing Services of Chicago wrote in The Chicago Greystone in Historic North Lawndale “If Lawndale’s Greystones could talk, they would tell us” of Golda Meir, Dinah Washington, Benny Goodman, Martin Luther King, Jr., and Clarence Darrow making a vibrant, dynamic neighborhood.

From: www.nhschicago.org/content/greystone.php

Like the brownstones of the east coast, Chicago’s greystones were two- or three-story, commonly 2 or 3 flats (though there could be up to 6), flat roofed, brick buildings with a façade of more fancy stone. There also were greystone mansions and one-story greystone “shoeboxes,” but not so many as to define a unified style. More then 93 percent have fewer than five residential units. Working class people of modest means, with some more affluent middle class folks, were the primary buyers and tenants. Some streets are entirely greystones flats, whereas others may contain just one or two greystones.

On the eastern seaboard, the stone embellishment was the 200-million-year old Portland Formation. Chicago builders, in contrast, took advantage of their proximity to the great limestone quarry region of Indiana and enhanced their brick with the 330-million-year old Salem Limestone. I won’t write more about these stones because I have covered them thoroughly in previous blog posts.

The survey found two stages of style. Initially between 1890 and 1905, primarily Romanesque buildings with rusticated limestone dominated. They featured arches and robust cornices. Next came a Neo-Classical look incorporating smooth limestone blocks, bay and Palladian windows, and columns. Throughout the era, many builders also built purely brick buildings in the same styles. Curiously the color of the brick changed from red to tawny.

From: www.greystonepreservationllc.com

Beginning in 2006, a consortium of groups banded together to form the Historic Chicago Greystone Initiative to preserve these wonderful buildings. Composed of community residents, non-profits, business, academic, and government partners, the Initiative promotes renovation and protection, through technical and financial assistance. They are doing vital and critical work. I wish them continued success.