Saturday, February 28, 2009

More Snows than Flakes

After this week's heavy rain and with a forecast of significant snowfall, I headed down to Eagle Bluffs Conservation Area on the Missouri River floodplain. Alas, the snow did not materialize, passing to our south, but the refuge did not disappoint.

A large flock of snow geese had settled on a flooded field, joined by shifting flocks of Canada geese, ducks and ring-billed gulls. Ducks were abundant throughout the preserve; at least 75% were mallards but squadrons of green-winged teal, groups of gadwall and stately pintails were also found. Raptors were out in force, including red-tailed hawks, northern harriers, kestrels, a lone sharp-shinned hawk and a pair of bald eagles. Surprises included a quintet of American white pelicans (a bit early for our region) and a trio of dunlins, probing a mudflat.

Other birds included horned larks along the roadways and the usual mix of winter songbirds in the woodlands. Mammals were out of sight on this cold, blustery afternoon, resting up for their nocturnal wanderings. Though the weather warned that winter has yet to retreat, the snow geese and their cohorts brought a promise of spring to this Heartland refuge.

Friday, February 27, 2009

The Western Nutcracker

Anyone who has hiked, camped or travelled in the higher elevations of North America's western mountains has likely encountered Clark's nutcrackers. These attractive birds, closely related to jays and crows, favor the upper Subalpine and Hudsonian zones, near timberline, where they feast on conifer seeds and insects.

Easily identified by their white, black and light gray plumage, these nutcrackers are often spotted at the top of a spruce or pine, surveying their territory. At other times, like their cousins, the gray jays, they appear at picnic sites, rest stops or ski resort decks to seek handouts from human visitors. In either case, they are handsome symbols of our high country and one of the more sought after species for birders new to the West.

Though Clark's nutcrackers inhabit high elevations throughout the year, they are an irruptive species and, in winters with low seed crops, they may invade the plains, parklands and deserts that surround the mountains. During these irruptions, which generally occur every decade or so, some individuals turn up far from their usual range, including coniferous woodlands of the northern Midwest.

Thursday, February 26, 2009

Spring Strikes

Though we've had some warm interludes and occasional rumbles of thunder over the past few months, today brought the first episode of spring-like storms, combining warm air, heavy rain and frequent lightening. The current weather system, now centered over northwest Missouri, is riding a late winter jet stream, which undulates across central latitudes of the continent. As a result, more heat and humidity have been swept northward, ahead of the front, igniting the thunderstorms and heavy precipitation; north of the storm, heavy snow will blanket the Upper Midwest.

This round goes to spring but winter has plenty of fight left and cold air will sweep in as the front pushes off to the east. But the struggle has been engaged and, over the next two months, spring will take control. Meanwhile, we'll endure a mix of raw and mild days, with all varieties of precipitation, perfect weather for the squadrons of waterfowl that will pass through the State.
So get out that rain gear, grab the binoculars and head for the wetlands!

Wednesday, February 25, 2009

Bad News and Stress

It's hard to be upbeat these days with a global economic crisis, ongoing war, dire warnings about climate change and daily catastrophes from across the planet. And, of course, all of this bad news is constantly updated by our faithful cable news correspondents. Even the Weather Channel, which should provide an escape from this carnage, insists on entertaining us with its series on natural disasters.

How to cope? Generally speaking, it's best to tune out. The constant bombardment of crises via online websites and cable TV can induce significant stress which, in turn, can contribute to a variety of health problems, from headaches to heart attacks. Over time, this relentless bad news, the preferred fodder of talk radio and cable commentators, can lead to symptoms of anxiety and depression.

Stay in touch with important news via a daily newspaper or via programs by PBS or the BBC, which provide a thorough but calm review of the day's major events. At the same time, come to accept that it is fruitless to worry about issues over which we have no control. Plan a period of daily, aerobic exercise to reduce stress and concentrate on what you can do to make your life more enjoyable and productive. Finally, we can all find comfort by contributing to the welfare of our species and our planet by volunteering our services to environmental, political or social support organizations; those engaged in rewarding activity are generally more optimistic and less stressed.

Tuesday, February 24, 2009

Conserving Habitat

Efforts to protect our wild plants and animals must focus primarily on the conservation of natural habitat and this is not as straight forward as it may sound. For any given class of habitat (e.g. woodlands) there are a vast diversity of subtypes (e.g. coniferous, boreal, deciduous, swamp, old growth, etc.) and most species are associated with a specific type of habitat. In other words, in order to sustain a broad diversity of species, we must protect a wide range of habitat.

To do so, we must ensure that our current wilderness areas remain intact, identify and protect threatened ecosystems across the globe and work to restore habitats that have succumbed to human impact (ranching, industrial pollution, residential sprawl and the introduction of non-native species, to name just a few). In addition, we must make an effort to keep our residential areas eco-friendly by protecting greenbelts, limiting unnatural vegetation, planting a diversity of native species and allowing open space to naturalize. Of course, our commitments to population control, clean and renewable energy and pollution mitigation are also vitally important.

While there are many conservation organizations that are devoted to these challenges (some are listed in the right column of this blog), I have long admired the work of the Nature Conservancy, which takes a practical, global approach to habitat protection and restoration. Though I have been a member for many years, I have no direct relationship with the Conservancy but hope that anyone who truly cares about the health of this planet will visit their website and support their efforts. Too many others are working against us.

Monday, February 23, 2009

Back to Winter

After a week in sunny (though not very warm) Florida, we have returned to the Midwest winter, with its frozen ground, biting wind and brown landscape. It's been a long, ugly winter in Missouri, offering severe cold but little snow. Even those of us who appreciate the varied seasons are ready for an early spring.

There are, of course, signs that the tide has turned. Birdsong has increased substantially since we left for the south and my morning walk to the University is no longer shrouded in darkness. But the early bulb plants remain suppressed by the frigid nights and the frozen ponds won't ring with the song of tree frogs until we enjoy longer periods of warmth.

Not that our sentiments are of any concern to Mother Nature. She will bide her time as we focus on our calendar, counting the days to the equinox. A flock of snow geese, calling in the night, is what my soul could use about now.

Sunday, February 22, 2009

Mangroves

Tolerant of saltwater, mangroves are represented by a wide variety of species that colonize tropical coasts across our planet. In the U.S., mangrove ecosystems are best developed along the Gulf Coast of southern Florida, from Tampa Bay to the Florida Keys.

Red mangrove shrubs are the vanguard of these coastal woodlands, forming the interface between water and land. Lining tidal streams, bays and inlets, these shrubs form dense thickets, easily recognized by the arching pattern of stilt-like roots that sprout from their lower trunks. These pioneer plants have adapted to their marine habitat by retaining fertilized seeds on their stems, where they germinate into small seedlings; released into the tidal waters, they float about until they encounter a sandbar or mudflat, where they quickly gain a foothold. Those not dislodged by storms or high waves grow rapidly and their tangle of roots trap sand, mud and organic debris; in doing so, the lone mangrove generates an island or peninsula as additional seedlings take root at their edge.

Just inland from the red mangroves is a band of black mangroves; also shrub-like, these trees are less tolerant of standing water and occupy sandy shores just above the high-tide line. Further inland are the white mangroves, which grow to heights of 30 feet in some areas. The ecosystem covered by these mangrove bands harbor a variety of wildlife, including wading birds that fish the shallows, raccoons that stalk the mudflats and mangrove crabs that climb the twisted branches; protecting tidal creeks from pounding waves, these evergreen woodlands also harbor vital nurseries for marine fish. Finally, mangrove islands are a favorite nesting site for brown pelicans, herons, anhingas and egrets, offering protection from land predators; unfortunately, the copious guano produced by these flocks will, in time, poison and kill the trees.

Looks Can Be Deceiving

One of my earliest childhood memories is of a flock of pelicans at a harbor in St. Petersburg, Florida. Since we lived in Cincinnati, that was my first exposure to these exotic and, in my recollection, comical creatures. Some were dozing on the dock while others gathered in the harbor waters, patiently waiting for handouts from the fishermen.

Today, I know that these seemingly lazy and odd-looking birds are among the most skilled and graceful residents of our southern coasts. Equipped with a seven-foot wingspan, brown pelicans cruise the beaches and bays with an effortless pattern of flaps and glides, often travelling just above the waves. At times, they gather near favored fishing sites, zeroing in on large schools of fish; circling above the prey, they dive toward the surface with a twisting, streamlined profile that belies their awkward, onshore appearance. Finally, their pendulous, lower bill serves as a natural net, scooping up fish as they knife into the sea.

Fortunately, there is a large population of brown pelicans around Longboat Key and I never tire of watching them. My fascination with this coastal bird, established at a young age, is sustained by both its entertaining antics and its impressive, natural talents. Any visit to the Florida coast would seem incomplete without their company.

Saturday, February 21, 2009

Eagles on the Bay

On our regular trips to Longboat Key, I almost always see a bald eagle or two. Of course, this is not unexpected since Florida, with its numerous waterways, lakes and coastal bays, has long been a southern outpost for our National Bird.

Since encountering my first bald eagle back in 1979, east of Little Rock, Arkansas, I have had the pleasure to observe hundreds of these majestic raptors in the wild. However, prior to this week, I had always seen them perched in trees, sitting on the nest, feasting on carrion (dead fish or waterfowl), flying along river valleys or soaring above the countryside. During this visit to Longboat, two adults settled in along Sarasota Bay, roosting atop a large Norfolk pine, just twenty yards from our condo. Now and again, one of the eagles would circle out over the bay and swoop toward the water, striking at fish with its powerful talons.

During some of these forays, an osprey, clearly threatened by the presence of these larger and more powerful predators, would swoop in to disrupt the hunt. The osprey, noticeably trimmer and more agile, reminded me of the crows and jays that attack red-tailed hawks in the Midwest; while neither the hawk nor the eagle is a significant threat to these smaller birds, they clearly sense danger and are determined to defend their turf. In the end (as occurred with this osprey), the relentless attacks pay off and the large hunters move on to a more tranquil site.

Sunday, February 15, 2009

Darwin and Denial

Three days ago, biologists across the globe commemorated the 200th anniversary of Charles Darwin's birth. Famous for his theories of evolution and natural selection, he has long been maligned by religious groups, who favor the Genesis account of creation. Indeed, surveys have demonstrated that, despite abundant genetic and fossil evidence, over 30% of Americans do not believe that humans evolved from other primates.

Human history is replete with similar figures who have been demonized by the Church; Galileo and Copernicus are two prominent examples. Scientific knowledge is a constant threat to religious doctrine, especially when it contradicts the "written word of God." The faithful find comfort in their simplistic view of the Universe and pour over scripture to find justification for their beliefs.

While scientists continue field and laboratory work to refine Darwin's theories, creationists rely on fear, guilt and ignorance to provide their receptive audience. It is indeed sad to realize that, two centuries after Darwin's birth, his thoughtful and groundbreaking work is still a subject of ridicule for a large segment of our society.

Saturday, February 14, 2009

Human Love

Human love is hard to describe and even more difficult to understand. Science purists often insist that it is simply nature's way to ensure the procreation and survival of our species. But anyone who has experienced love knows that it is something more than sexual attraction.

And, despite the rhetoric of the online matching services, there seems to be little relationship between love and compatibility. Love is not always mutual and, as many come to realize, it does not always guarantee a happy ending; unrequited love is surely one of the worst fates that humans can endure. While some believe in the "one and only" theory and others claim to have never been "a victim of love," most of us have been in love more than once; though, for one reason or another, the relationship may whither, few would deny that love, itself, endures.

So, how to summarize the nature of love on this holiday of hearts? As intellectual beings, we are intrigued by love but cannot define its essence. It must be felt to be known. And once it dwells in our soul, it will not leave.

Friday, February 13, 2009

No More Roads

Faced with global warming, suburban sprawl, loss of natural habitat and an economic crisis, I propose one primary solution: no more roads! The continual effort to expand and widen our network of roadways encourages our dependence on automobiles and fosters an excessive use of fossil fuel. At the same time, these ribbons of concrete facilitate the suburban lifestyle, pushing out our city limits and chewing up our natural ecosystems.

The use of Federal funding to develop light rail, commuter rail lines and high-speed rail between major cities would create jobs and, hopefully, encourage a radical change in American society. Inner cities would be revitalized, oil consumption would drop, CO2 emissions would fall and open space would be preserved. At the same time, investment in clean and renewable forms of energy would further stimulate the economy and provide the means to power these mass transit networks.

Of course, roads, cars and trucks will not be disappearing any time soon; it would be impractical to suggest that we can stop maintaining and repairing our current transportation system. But we can easily decide to stop building new roads and widening the old ones; otherwise, we will never take a major step toward the mass transit model. Unlike Europe, the U.S. has so much open space that we often lose sight of its value.

Thursday, February 12, 2009

The Great Divide Basin

Most Americans envision the Continental Divide to be a continuous range of high peaks, dividing the watersheds that flow toward the Atlantic from those that drain toward the Pacific. While this is, in general, true, there are some relatively low ridges that connect the component ranges and, in one area, a bifurcation of the Divide itself.

In south-central Wyoming, the Continental Divide, dropping from the crest of the Park Range in northern Colorado and from the Wind River Range in central Wyoming, splits to encircle a broad, desert basin. Known as the Great Divide Basin, this remote and scenic area is rimmed by mesas and covered by sand dunes, alkali flats, badlands and sage grasslands. Much of the Basin exceeds 7000 feet in elevation and its 5 million acres, part of the Red Desert of southwest Wyoming, stretch between Rawlins and Rock Springs; I-80 crosses its southern portion. This topographic basin is bordered by the Sweetwater watershed to the north, the Green River watershed on the west, the North Platte watershed on the east and the Yampa watershed to the south; streams draining inward from the basin's rim end in shallow, ephemeral lakes on the flat, desert floor.

Home to a wide variety of high desert wildlife, the Basin also harbors large quantities of uranium, oil and gas, setting the stage for an ongoing struggle between industrial powers and environmentalists. Most of the area is owned by the Bureau of Land Management, a sign that industry will likely have the upper hand. If it were up to the plentiful pronghorn, this vast, scenic landscape would soon be a National Park.

Wednesday, February 11, 2009

Flood Season

In the Midwest, the flood season runs from mid February to mid April. Heavy rains, melting snow, frozen ground and dormant trees combine to increase runoff and rivers, partly clogged by ice jams and flotsam, spill across their floodplains. This annual deluge, a recurrent nightmare for those who live along these waterways, once spawned vast wetlands and swamp forests; today, most of the floodplains have been cleared for crop fields and industrial ports.

Leaving swaths of shallow lakes, sloughs and flooded fields, this seasonal pattern coincides with the spring waterfowl migration, offering nutritious rest stops for the huge flocks of geese, ducks, coot and grebes that cross the Heartland on their way to northern breeding grounds. Migrant snow geese will be moving through in late February, followed by the Canada geese in early March; ducks peak in number and variety from mid March to early April.

As the weather warms in mid spring, the ice jams clear, the soil absorbs much of the moisture and the trees, festooned with new leaves, begin to transport much of the rainfall back to the atmosphere. Though stagnant weather patterns may produce regional flooding throughout the warmer months, the annual cycle is generally over by May.

Tuesday, February 10, 2009

Natural Death

Having practiced medicine for over 30 years, I am well aware that it is often difficult to achieve a natural death, devoid of tubes, a ventilator and the hospital environment. Despite the positive influence of the hospice movement, many dying patients are subjected to unnecessary and fruitless medical and surgical intervention. At times it is in response to the expressed wishes of the patient, though often confused by the emotional interpretation of family members. At other times it is due to the overzealous efforts of attending physicians, conscious of potential litigation and determined not to fail in their quest to prolong life.

This week, the Supreme Court of Italy is hearing arguments regarding the right of a family to withdraw nutritional support from a comatose relative. They are being challenged by the government and the Vatican which, of course, have their own political and religious agendas. In such cases, opponents of removing life support generally invoke the position that "we have no right to play God." I would argue that it is the medical establishment, under the direction of the patient, family or court that is attempting to forestall a natural event; and while the patient and his family certainly have the right to make this choice, the government and the Church have no place in the discussion.

There is a certain irony that religious institutions, with their expressed mission of preparing us for the afterlife, should take such a strong stand against efforts to withdraw artificial life support. In their opinion, we are obliged to use our God-given talents to sustain human life, no matter the circumstances. In my opinion, we often treat our pets more humanely than we do our fellow man.

Monday, February 9, 2009

A View to the West

My office window at the University of Missouri commands a broad view to the west, the perfect direction for Midwestern weather buffs. Before dawn this morning, a brilliant full moon set behind a flat bank of clouds, just above the western horizon. Flags atop the ROTC building fluttered in a gentle, south breeze, a hint of change to come.

By mid morning, a swath of high clouds had reached Columbia and the flags were rippling in a strong south wind. A few hours later, low, dark cumulus clouds covered the sky and sheets of rain pelted the city. Though the precipitation has diminished this afternoon, the flags still signal a strong south wind, a message that the approaching front is still well to our west. Forecast to arrive tomorrow, the front, tied to a potent low, will produce lift and converging winds, setting the stage for thunderstorms.

My view, complemented by the cloth weather vanes, is usually as reliable as a check of the local radar. Over time, one learns to appreciate the signals that nature, herself, provides.

Sunday, February 8, 2009

The Common Recluse

One of the least conspicuous birds in the eastern U.S., the American woodcock is a chunky "sandpiper" with short legs, large eyes and a long bill. Though often grouped with shorebirds, the woodcock and its cousin, the common snipe, are inland birds that favor moist woodlands, bottomland meadows and streamside thickets. There the woodcock hunts at night for earthworms, grubs and a variety of insects; it is seldom seen by the casual naturalist.

This locally common but reclusive bird winters across the south-eastern U.S. but summers as far north as southern Canada. Hardy, they arrive on the breeding grounds by late winter and it is then (mid February to mid March) that birders have a chance to observe the aerial displays of the adult male. After spiraling into the air and then circling above a marshy field, he plummets toward the ground in a zigzag pattern, wings whistling; those hoping to observe this rite, which usually begins at dusk, should seek out meadows near riparian woodlands and listen for the sharp "peents" of the male suitors.

Woodcocks nest on the ground, usually beneath shrubs or thickets. Both parents share the incubation and child rearing duties and their young are independent within a month. Until autumn, they will doze in dense cover during the day, arousing at dusk to hunt their favorite quarry. When accidentally flushed by hikers or dogs, they explode into the air (in the manner of quail) and zigzag into the deeper woods. Good luck catching one on film!

Saturday, February 7, 2009

Fair Warning

Mild air has pushed into mid Missouri over the past few days, with afternoon highs in the upper sixties. But such warm spells in early February portend a coming change. We are now on the roller coaster toward spring, with its exhilarating climbs and chilling drops. There is still plenty of cold air in the North Country and, while approaching fronts pump warm air from the south, they also pull down Canadian air on their backside. Our next front is due tonight and tomorrow's high will be in the forties.

This undulating pattern, typical of late winter and early spring in the Midwest, is governed by the jet stream which, during this season, is inching its way back to the north. In the South, where the passing fronts create especially warm and humid conditions, it is the season of severe thunderstorms, some of which are tornadic. For those of us in the Heartland, the pattern produces dramatic change from week to week which, depending upon one's view, yields variety or frustration. For now, we'll enjoy this warm interlude before winter strikes again.

Friday, February 6, 2009

River of Grass

As sea level rose and fell over millions of years, the Florida Platform, wrenched from Africa when the Atlantic Ocean opened, has been covered by numerous layers of sediment; these deposits have since solidified into a mosaic of limestone formations, which vary in composition and porosity. Over time, these rocks have been sculpted by tropical rains, hurricanes, waves, rivers and invading arms of the sea; deeper, porous layers have become aquifers while harder, surface formations define the modern landscape.

The Everglades ecosystem, which includes Lake Okeechobee, has developed within the past 6000 years, well after man had settled parts of the peninsula; indeed, archaeological records indicate that he had reached Cuba by 7000 years ago. Fed by the Kissimmee River and a number of smaller streams, Lake Okeechobee formed in a broad, shallow basin, which spills southward onto a flat plain; the latter, bordered by higher ridges to the east and west, dips gradually toward Florida Bay, at the southern edge of the State. During the wet season (June to November) the Lake would overflow onto this plain and a shallow "river," sixty-miles wide, would move steadily toward the coast, covering the 100 mile distance in 200 days or more.
This produced the Everglades ecosystem, with its vast expanse of sawgrass and isolated hammocks of pine, palm and subtropical hardwoods; these woodlands occupy islands of higher terrain where hard sediments have resisted erosion.

World renowned for its fabulous scenery and diverse wildlife, the Everglades have been under constant siege since white settlers colonized the State. Water diversion, fire suppression and pollution have all taken a toll. Today, Lake Okeechobee, the natural source of this River of Grass, is ringed by a levee, controlled by floodgates and choked with pollutants (primarily from agricultural lands to the north). Though recovery efforts continue, it may be too late to fully restore this fragile ecosystem.

Thursday, February 5, 2009

Joyous Mourning

On my walk to work this morning, the plaintive call of a mourning dove rang through the predawn darkness; the temperature was 20 degrees F. No leaves grace the trees and no flowers adorn the lawns. Baseball is relegated to the South for another two months and the fragrance of wet soil is just a memory. Winter still grips the Heartland.

But, unlike humans, wild creatures are more responsive to the solar cycle than they are to the daily weather. Despite the polar air and human calendar, this dove has sensed the coming spring and, in doing so, assures her skeptical neighbors that nature's cycle remains intact. For that, we are most grateful; her familiar, mournful tune, an omen of early spring, is welcome music to the ears of winter weary humans.

Wednesday, February 4, 2009

Assumptions, Beliefs and Truth

Throughout most of human history, man assumed that he lived on a flat landscape, circled by the sun, the moon and the stars. Devoid of scientific knowledge, he associated natural forces with powerful beings, to which he paid homage and offered sacrifices. Of course, his assumptions were based on his perspective and, over time, this perspective has changed.

Beliefs are assumptions that have become ingrained in our culture. Since science cannot always prove nor disprove them, they persist. Many equate them with truths, handed down by beings more knowledgeable and more powerful than ourselves. Others recognize that these beliefs are a natural trait of the human mind, sustained by fear, guilt and ignorance.

Truth can only be uncovered through scientific inquiry and, as our scientific knowledge and tools advance, assumptions and beliefs are tested. Those who distrust science, or are threatened by it, are quick to point out its history of error; but, in reality, it is science that uncovers its own mistakes. We rely on our current scientific knowledge to understand this Universe, knowing full well that today's breakthrough may be tomorrow's folly. Nevertheless, the search for truth continues; the future welfare of our species depends on that quest.

Tuesday, February 3, 2009

The Edwards Plateau

Looking at a map of Texas, one notices that its many rivers flow from northwest to southeast, toward the Gulf of Mexico. On closer inspection, a noticeable gap is seen in the south-central part of the State, where few streams are observed between the Colorado River, to the north, and the Pecos River, to the southwest. This is the extent of the Edwards Plateau, a geophysical province that slopes gradually downward from northwest to southeast; elevations at the west end of the plateau exceed 3000 feet while valley floors along its southeast edge are only 300 feet above sea level.

The thin soil of the Plateau overlies a thick deposit of Cretaceous limestone which, in its eastern and southern sections, has been heavily dissected to yield the Texas Hill Country. The northwest edge of the Plateau abuts the High Plains of the Panhandle while, southwest of the Pecos River, the Chihuahuan Desert begins. Along its northern border, bisected by the Colorado River, is the Llano Uplift, where the Cretaceous limestone has been stripped away, leaving outcrops of Precambrian granite and metamorphic rock.

The poor, thin soil of the Edwards Plateau, not ideal for farming, has been used primarily for grazing. Once deposited in a shallow, transcontinental sea, the limestone beds now support rolling grasslands and open woodlands of mesquite, juniper and oak. Marine life has given way to cattle, sheep and goats!

Monday, February 2, 2009

South Park

About 50 miles southwest of Denver, U.S. 285 crosses Kenosha Pass, which separates the watersheds of the North and South Forks of the South Platte River. From a parking lot at the pass, one is treated to a broad view of South Park, one of four intermountain basins that stretch through the Rockies of Central Colorado. Quilted with hay fields and cattle ranches, this scenic parkland attracts pronghorn, mule deer and wintering herds of elk; of course, it also attracts the predators that feed on them: coyotes, black bear and mountain lions.

The Continental Divide curves along the north edge of the basin, crossed by Hoosier Pass in its northwest corner. Somewhat lower but no less scenic, the Mosquito Range forms the west edge of South Park while the Platte River and Tarryall Mountains rise to the east. The South Fork of the South Platte receives tributaries from all of these highlands and flows southward across the basin; the rise of the volcanic Thirty-Nine Mile Range, during the Oligocene, closed off the south edge of the Park, forcing the river to angle southeastward (towards Pike's Peak) and then northeastward through the Front Range foothills. The North and South Forks join in these foothills before the South Platte rumbles onto the Piedmont in southwest Metro Denver.

The geology of South Park is complex, the result of Precambrian ranges rising through flat beds of Paleozoic and Mesozoic sediments and subsequent erosion by mountain glaciers and streams.
Red Hill, a long hogback of Jurassic and Cretaceous Rock, knifes through the center of the Park, separating Paleozoic bedrock to its west from late Mesozoic bedrock to its east; both have since been covered by erosional and volcanic debris, which nourish this magnificent grassland.

Sunday, February 1, 2009

February

We are over the hump. The average temperatures are rising and the days are gradually lengthening. The jet stream, which governs the flow of cold and warm air is inching its way to the north, ushering in labile weather patterns; polar fronts will still push south but the frigid air won't persist for weeks at a time. The February sun, still low in the sky, will add little to the warm spells; those initial episodes of spring fever will arrive on southerly winds, produced by the jet and its Pacific fronts.

But, though winter is far from done with the Midwest, the signs of seasonal change will appear throughout the month. Warming of the upper soil will trigger the bloom of our first wildflowers: snowdrops, winter aconites and crocuses. By mid month, birdsong will echo through our neighborhoods, ending a long, quiet season that began in November. And, before February ends, the geese will begin their northward migration, great horned owls will be on the nest and tree frogs will call from the shallows.

This is a month for patience. Signs of spring will mix with the last gasps of winter and nature will move at her own, unpredictable pace. We might as well savor each day, knowing that, soon enough, we'll come to loathe those hot, humid days of summer.