Riding my bike along the Little Juniata River on a beautiful spring evening earlier this week, I was grateful to have the time to be out and about.  Though the bleak, leafless trees of early spring were not nearly as beautiful as their green foliage of summer, I was enjoying the scenery along the river, still swollen by the spring runoff.

A large bird flew overtook me from behind, crossed the river and landed in the trees on the opposite side of the river.  I could tell from its general shape and size it was some sort of raptor.  Moving along at a brisk pace, I didn't want to interrupt my ride.  Suddenly, it occurred to me that the bird might be worth a second look and I turned around for a better look.  I approached as slowly and quietly as I could and soon realized it was a bald eagle. It flew off before I could snap a picture, but it made my day just the same.  I had not been that close to a bald eagle in quite a few years and it got me thinking about how endangered the bird was earlier in my life.

My stream of consciousness meanders in unpredictable directions at times and this chance meeting between a bicyclist and a bird got me thinking about several related topics.  We are fortunate today we can find the American Bald Eagle anyplace beyond its image on our money.  The population of the iconic bird plummeted in the middle of the twentieth century, thanks to several pressures put on the species.

Chief among the problems was the effect of chlorinated pesticides like DDT, Chlordane, Kepone and several other related insecticides.  Beyond a host of other problems, this family of bug killers interferes with the metabolism of calcium.  In animals that lay eggs, this causes the thinning of the eggshells.  Particularly with eagles and hawks, the weight of the brooding parents often cracked the eggs long before the young birds were fully developed.

To add insult to injury, the young eaglets that did survive often died of pesticide poisoning.  Though the levels of pesticides rarely killed an adult bird, the smaller birds were susceptible.  Nature author Rachel Carson wrote about this poisoning in her classic Silent Spring 55 years ago but she was ridiculed by the pesticide industry and other adversaries for being an alarmist, hysterical woman.  Ten years passed until DDT was ruled illegal for use in the US.  Many related chemicals were not outlawed until 1988.

DDT and its related chemical cousins became a problem because they are persistent, bioaccumulative and toxic (PBT).  In simpler English, it means they breakdown very slowly and accumulate in fat tissue (since the chemical are derived from petrochemicals and are fat soluble).  The very things that made them effective bug killers made them a much bigger problem to human health, as well as birds of prey.  The eagle and DDT stories reminded me of the value of well-researched, scientifically-based environmental regulations.  Our majestic national bird still flies through the skies of Blair County, and much of the rest of the nation, because of them.

The United States National Park Service began its 100th anniversary celebration this summer and it gives us an opportunity to reflect upon both its past and future.  Many of us have indeed been touched or inspired by at least one special place in the park system.  Some have been fortunate enough to have been impacted by several dozen. 

Though the Park Service was established in 1916, nine National Parks predate formation of the agency.  The oldest, Yellowstone National Park, dates back to 1872.  The Park service now oversees 413 units, including 59 National Parks; 114 National Monuments and Memorials; 154 National Historic Sites, Parks and Battlefields; 29 National Seashores, Lakeshores and Rivers; and 19 National Preserves.  They are not only diverse in their nature and focus, they vary greatly in size as well.  Some of the National Monuments and Historic Sites are less than an acre, while Yellowstone, Death Valley and six Alaskan parks and preserves encompass more than two million acres. 

Regardless of size or location, many Park Service sites share common challenges, both now and in the future.

• Long-term upkeep – Contrary to popular thought, parks don't take care of themselves just because they are left in their natural state.  Particularly in parks with high volumes of visitors, the pressure exerted by that many people taxes every part of the man-made park infrastructure as well as the natural amenities.  It costs money to stay ahead of all this and Congress has often postponed paying those bills.  One recent estimate set the backlog of maintenance and upkeep work at $11 billion.
  
• Crime and vandalism – Vandalism problems add insult to injury.  Iconic rock formations have been destroyed, graffiti painted on park treasures and monuments seriously damaged.  Crime of all sorts is a growing problem and a notable portion of the staff in the larger parks must be devoted to enforcement personnel.
• Congestion – The automobile traffic in the most popular parks can be overwhelming during the summer months.  I had an inkling of this as far back as 1973 when I went through Grand Canyon National Park for the first time, but it was hammered home in a most unpleasant way five years later in Yellowstone.  Looking forward to experiencing one of the most famous parks by bicycle, we were so overwhelmed by the trailer and motor home traffic that we passed up Old Faithful and exited the park by the less congested eastern route.
  
• Managing the people – Beyond the traffic, just managing the people can be a gargantuan task.  The upper parts of the trails in Grand Canyon are so busy at times that hikers frequently have to stop to let other trail users (including the pack mules) pass by.  Campgrounds, parking areas, bathrooms and the staff that oversee them are stretched to their limits in the peak seasons.
• Adjacent land use – Though many communities near National Parks understand the value of encouraging or requiring compatible land use, some mighty ugly things have sprung up in the most inappropriate places.

Writer and environmentalist Wallace Stegner observed thirty years ago that "National parks are the best idea we ever had."  Like other good ideas, it's clear we need to work hard to keep this one alive.

You can read more about the anniversary by visiting the National Park Service.

Those folks connected a bit too closely to their electronic devices are missing some very interesting things in the natural world.  Some are not that far from our own back doors.  I am especially reminded of this following some unusual encounters with some furry, scaly and feathered friends over the last few months.

A large family of wild turkeys visited my yard this past Sunday.  I might have missed them had it not been for the gobbling of one of the adults trapped behind a pasture fence.  The other adult bird and ten chicks were on the other side of the fence and the trapped turkey was frantically racing back and forth looking for a way out.  Turkeys spend much more time on the ground grazing than they do in the air, so this panicked bird scampered about for several minutes before it evidently remembered it could fly over the fence.  When the bird finally escaped its unexpected prison, it scurried (again on foot) to catch up with the rest of the flock.

A few weeks before the turkey incident, I ran into a couple other smaller birds on a bicycle ride.  When I say I ran into them, I mean it quite literally.  In four decades of riding, I have run over chipmunks, small snakes and collided with countless insects.  But this was the first time I'd ever been hit by birds in flight.  The two were evidently distracted as they tussled with each other in midair, disregarding this passing cyclist and smashing into my chest.

Not far from the Tipton Reservoir, I noticed an uncommonly large rabbit grazing along the roadside on several rides earlier in the summer.  I thought it unusual when the rabbit kept showing up not far from the spot I first saw him.  Finding the animal and its behavior to be a bit of an oddity, I stopped one evening to take a picture.  The rabbit stood calmly eating, unfazed by my close proximity.  The photo and some internet research helped me determine it was a domesticated bunny, an American Sable.  I can't say whether someone claimed the animal or if a predator took advantage of its trusting nature, but it disappeared in late July.

In a twist on the tortoise and hare story, I also came upon several turtles during that same span of time.  I passed one on River Road near Tipton but, on pace for a particularly fast ride, didn't stop to help the slow moving reptile across the road.  I felt guilty for days, fearing the turtle might have been run over before it got to the other side.

Later, I saw another one making its way across Route 453 outside Tyrone.  A much busier road, I feared the odds this turtle would make it across were not good.  I stopped and turned around to see an SUV bearing down on the unhurried reptile.  The driver stopped, waved me onto the road and I gently slid the reptile across to safety.  This summer of unusual wildlife again proves to me there is much to see beyond the screen of our smart phones.

I didn't mosey too terribly far from home this summer.  Yet I managed to experience some interesting things.  While I saw some of them from the saddle of my bicycle, I realized recently that much was happening in my own backyard.

We often see hawks and geese around our home but were treated to visits from two other large birds that most of us don't see as often.  Just a week after spotting a Golden Eagle flying off with a fish from the Little Juniata, another one of the majestic birds landed in a tree in my yard.  In the last few weeks, a large family of wild turkeys have been wandering around my yard, the first time that I can recall seeing that many near my home.  Though we welcomed those visits, not all my interactions with the wildlife have been pleasant.  The rabbits and chipmunks ate vegetables and flowers I didn't think any animals would eat, including marigolds, geraniums, peppers and green beans. 

Our weather, as it so often does, presented its own set of challenges.  While our family enjoyed a bumper crop of strawberries and potatoes, the raspberries and grapes were done in by an uncommonly late frost.  (Ironically, this came after an otherwise warm month of May.)  That late season frost (from which most city dwellers were spared) was just one of a bundle of unusual weather events.  After nearly four weeks of warm and dry weather in May prompted a drought warning, a spell of rainy weather began that stretched into the second week of July.  It resulted in one of the wettest Junes on record.  Another dry spell threatens to push us near a late summer drought.

After losing two beautiful white birch trees over the last five years, a middle-aged oak tree and a colorful redbud died this year.  (Some call the beautiful flowering tree "deadbud" because of its notoriously short lifespan.)  My greatest loss these last two summers has been the death of six white ash trees.  The emerald ash borer, a native of Asia accidentally introduced to the United States in the nineties, has decimated the tree throughout much of Pennsylvania.

The ash trees, fortunately, are the exception this summer, as the overwhelming portion of trees are thriving in the Pennsylvania summer.  The oak behind my garage looks healthier than ever, two fine-leafed Sunburst Locusts in my front yard have grown to impressive heights.  A stately Tulip Poplar, the trunk characteristically straight, continues to reach skyward along my northern property line.  The White Pines, damaged by some heavy snow last winter and plagued by the White Pine Weevil a decade ago, seemed to have weathered those storms and have done well in recent years.  Two hemlocks have, at least so far, survived the woolly adelgid that has killed so many of our state tree in the last decade.  No doubt, a Pennsylvania summer can present its share of tribulations.  But it usually manages to present us with many more gifts than curses.

Winter is not only the coldest time of the year but its early weeks also bring the shortest spans of daylight.  The hours of daylight recently dipped below ten hours here in central Pennsylvania and we're still a month from the winter solstice.  The length of our days and the trend of declining temperatures are directly related to the height of the sun in the sky.  The sun will continue to drift closer to the horizon until the shortest day of the year just before Christmas. 

On our winter solstice, the sun is directly overhead the Tropic of Capricorn (23.5 degrees south of the equator), the southern-most point that overhead rays reach.  That means that the solar radiation that reaches our Northern Hemisphere is at its lowest.  Above the Arctic Circle (23.5 degrees from the North Pole) the sun is not seen at all on the Winter Solstice.  The magic 23.5 degrees keeps coming up in our conversation because that is the tilt of the Earth on its axis.  That tilt means that the height of the sun in the sky changes from season to season.  Altoona, about 40.5 degrees north latitude, never experiences direct overhead sunlight, being located 17 degrees above the northern border of the tropics, the Tropic of Cancer.  That tropical border line is just below the southern end of the Florida Keys.

We all recognize that average temperatures generally drop as we move away from the equator and toward the poles (where the sun is much lower in the sky).  Shallotte, NC (34 degrees North Latitude and directly south of Altoona) is, on average, 18 degrees warmer than Altoona at this time of the year.  Riviere-Heva in northern Quebec, Canada (48 degrees North Latitude and due north of us) averages high temperatures 17 degrees colder than ours in late autumn.  We sometimes forget that the length of day and night are also influenced by our distance from the equator.  Shallotte, NC gets 35 minutes more daylight than we do in mid-November.  Riviere-Heva has a 38 minute shorter day than what we have here.  The sun will go down at 4:27 p.m. this afternoon in the remote Canadian town.

There is an upside to these short days in the wintertime; there are correspondingly long days in the summer.  An 8:20 day in Riviere-Heva near the first day of winter is replaced by a 15:40 long day on the Summer Solstice six months later.  The longer day and higher sun help bring an average high of 70 degrees in late June.  I met Alaska's state champion, Bill Tetraut, at the national bicycling championships some years ago and our conversation inevitably turned to our training challenges.  He lamented that winter and spring training could be very difficult that far north. 

Summers were another matter.  Besides the warmer weather, nights were only a little more than six hours long where he lived and he could safely ride until 11 p.m. for several weeks in early summer.  This interesting tilting of our planet, then, brings the seasonal temperature variations and changes in the length of our days and nights.  After living through a few decades of these changes, we often forget how these little things can change our lives in very big ways. 

Living among the mountains of central Pennsylvania day in and day out, sometimes we don't notice the natural beauty of our forests.  From far-off, the deciduous trees on the mountainsides look like green puffs of moss.  As we ride or walk through those trees, we see the woods from the inside looking out, rather than the other way around.  From within the woods, we may simultaneously experience the forest as a whole while also seeing the beauty or uniqueness of individual trees, plants or animals.  The inanimate parts of the forest – the waterways, the rocks and soil – at once make the background and frame of the picture.  Frequently, the experience is enhanced because it can encompass all our senses.  It is not just pretty scenery; it is the smell of the flowers and evergreen trees, the sound of the singing birds, the rush of the water over the rocks, the feel of the damp summer air rising from the forest soil.  

At this point in the summer, one of the most overlooked but beautiful sights are the flowering wild rhododendrons that can overwhelm cool and shady hillsides and stream valleys.  Not to be confused with its domesticated cousin found in many home landscapes, the native variety blooms much later and has smaller flowers.  What it may lack in flower size, however, is more than compensated for by the abundance of blooms.  Though a leafed plant, rhododendrons are evergreens and (like needled trees) are a favorite spot for deer looking for shelter in the winter.  Their evergreen leaves have another unique characteristic seen in the winter time that has given them the nickname, "Mother Nature's thermometer."  As it gets colder, the leaves of the plant curl up, giving the illusion that the plant is dying during prolonged frigid spells in the winter.

Preferring cool, shady and damp areas, rhododendron are seldom seen in open fields.  They are an understory bush common in hollows and stream valleys, but may also be found on the edges of woodland along roadsides where direct sunlight is sporadic.  Feeling at home in the same sort of environment as hemlock trees, rhododendrons and mountain laurel often team with our state tree to provide those rare splotches of green in the winter forest.  Native rhododendrons are sometimes confused with our state flower, the mountain laurel.  Their flowers are similar but the leaves of mountain laurels are smaller and flowers bloom much earlier than the wild rhododendron.

The range of the rhododendron is wide, stretching from southern Canada to northern Georgia.  They are much less common in eastern Pennsylvania than they are here in Appalachian Ridge and Valley and Allegheny Plateau.  They tend to be most prolific here in Blair and Bedford counties in the sheltered stream valleys of the Allegheny Front.  My favorite "Rhodie Shows" are on the roadways that parallel Burgoon Run (above the Horseshoe Curve), Bells Gap Run (west of the Bellwood Reservoir) and Tipton Run (both above and below the beautiful stone dam of the Tipton Reservoir).  While the peak of the flowering may have recently passed for this year, you can still get out there on the trails or roads this weekend to enjoy one of those unappreciated gifts of the Penn's Woods.

Trees – they may be Mother Nature's most underrated asset.  They take in carbon dioxide and produce oxygen.  They absorb odors and several common air pollutants.  Particulate pollution is trapped on their leaves.  Trees provide habitat for all kinds of wildlife.  Their roots stabilize stream banks and prevent soil from washing off the sides of mountains. It is no coincidence that our local water authorities work hard to protect the trees on their watersheds.  Tree cover moderates temperature extremes.  Their shade cools the streets and soil beneath them in summer.  They slow heat loss from buildings in the winter.  That means they also slow evaporation from the earth's surface, slowing the effects of drought and protecting nearby plants from the stress of dry spells.

What other material on the planet is renewable, a durable building material and can be burned for energy?  A number of species produce edible fruit or nuts.  As if we had not already described a near perfect creation, even the waste material from trees (their leaves and needles) is easily converted into valuable nutrients for the soil.  In nature, the leaves fall to the ground and their nutrients are recycled beneath the tree itself.  We can also make rich compost when we transform leaves and grass into a soil amendment in our home composters or at our facilities at the Buckhorn or near Duncansville.  Yet it goes beyond just the traditional environmental benefits.  Neighborhoods with more trees have lower crime rates and higher valued real estate.  People prefer to live and work in places with more trees.

Trees soften harsh urban features or rural blight. It masks some of the less attractive things we build and allow to pile up in our man-made landscapes.  Many of these benefits are subtle and unappreciated.  But sometimes, trees actually make the news.  Like other perceived injustices, the public speaks out when something happens to their trees. 

Trees have made the local news several times over the last few weeks.  Altoona City officials concluded that the damage to several dozen trees on Broad Avenue was even worse than first feared.  Residents and those that use Broad Avenue have been upset because the stately trees on the shady thoroughfare were butchered in an ill-advised tree trimming endeavor.  Though some of the trees were old and in declining health, it would seem that replacing a small number of trees every few years would have been a preferable strategy.

Altoona and Hollidaysburg are both Tree City USA communities recognized by the National Arbor Day Society and have worked hard in recent years to preserve old trees and plant new ones.  Like Altoona and many other communities, Hollidaysburg also has street trees in decline and recently announced a plan to plant two dozen each year over the next five years.  Though Altoona has also had some struggles with some older trees on Eighth Street, their street tree planting efforts have provided many of the benefits we described earlier.  Many surrounding communities can also boast of pleasant tree-covered streets and mountainsides.  Here is a hope that we value all the benefits they bring and continue to work to preserve them.

The Penn State Cooperative Extension and the Arbor Day Society both have great resources on tree pruning and care. 

I have long been fascinated by lightning bugs.  Several nights this week I sat on my back porch, mesmerized by one of nature's most interesting light shows.  Lightning Bugs are miraculous insects, carrying their own light source by way of a chemical reaction that they create themselves.  It was not just the miracle of the fireflies, though, but the absence of man-made sounds that made me smile those nights on my porch.  Though there were plenty of sounds of nature, the harsh, abrupt, often annoying sounds made by humans and their machines could not be heard at that late hour.

Earlier that same day, a bicycle ride took me through rural Huntingdon County.  As the wind blew in my face, I was struck by the sweet smells of the clover family and later by the cool, moist air along Spruce Creek.  That humid air could be felt as much as it could be smelled.  The next day, I had the pleasure of visiting Brother John Kerr at Saint Bernadine's Monastery near Newry to talk about their sustainability and environmental stewardship initiatives.  As we walked through the stunning grounds and gardens, I looked eastward and saw the end of Dunning Mountain.  Most of the ridge is covered in trees, but where soil never developed, large fields of Tuscarora Sandstone boulders litter the mountainside.  The mountain does not look much different than it would have long before man set foot in the valley.

Folded by crustal collisions that occurred a quarter billion years ago, these mountains are stubs of what were once much larger and more spectacular highlands.  Despite their smaller scale, they remain a scenic treasure, a source of clean air and high quality water and a vibrant habitat for a diverse collection of flora and fauna.  This flood of different sensory experiences – the smells, the sounds, the sights, the feelings – made me think about a bigger picture point, that the Earth itself is a miracle and an oddity.  It is too often taken for granted.  Astronomers have concluded that Earth-type planets are rare indeed, for the conditions that make an environment like ours is unusual.  As Goldilocks has so often been quoted, we need something "just right" to make the conditions for life as we know it.  In our own system, we are the solitary planet that supports advanced life, the inner planets being too hot, the outer ones too cold.

Our Goldilocks planet has a temperature range that allows water to exist most frequently as a liquid, one of the keys to the evolution of larger plants and animals.  Yet we have a rather cavalier attitude about the planet, locally and around the world.  Too often, our peaceful firefly-filled evenings are shattered by the din of a motorcyclist that has altered his mufflers.  Mountainside vistas are spoiled by a poorly planned development or an obtrusive billboard.  The smells of summer are too frequently overcome by a smoldering burn barrel. 

Those seem like odd things to do to a planet if it really is a one in a million oddity.

America is a fascinating place.  Being a geographer (and the son of two geographically curious parents), it is the landforms and landscapes that I find to be especially interesting.  A plane flight to Texas (just a few days before a hurricane) gave me a chance to see some of that geography from 35,000 feet.  Even on a hazy day, the view can be spectacular.  I am always struck by how many people get on a plane and never even look out the window.  I, by contrast, am disappointed when the clouds get in the way of a great view.  For those of you that don't fly much or have forgotten there was a beautiful America below you when you fly, permit me to share a few geomorphology lessons.

• The Coastal Plain – My journey began at the Baltimore-Washington International Airport on the Atlantic Coastal Plain.  All of us that have been to the beach understand how starkly different this region is from where we live.  This same flat, sandy landscape runs from Cape Cod to the Texas Gulf Coast.
• The Blue Ridge – A much harder group of rocks than those in our Ridge and Valley, the Blue Ridge stands taller than our central Pennsylvania mountains.  Having been metamorphosed by heat and pressure, they not only stand higher but have a different shape that is easy to see from the air.
• The Appalachian Ridge and Valley – The gentle folds of our own Ridge and Valley province look like a wrinkled green sheet from high in the sky.  Once much higher mountains when they were originally folded 250 million years ago, they are actually stubs of those ancient peaks.
• The Appalachian Plateau – Uplifted but not as badly deformed as the Ridge and Valley, the plateau begins on the western edge of Blair County.  Rich in coal deposits, the strip mines are one of the most noticeable features from the air.  (And they don't look any more attractive from the air than from the ground.)  The plateau runs from New York to Northern Alabama and actually continues as the Ozark Plateau on the other side of the Mississippi.  As the plateau fades away in northern Alabama, we passed over dams built by the Tennessee Valley Authority.
  
• The Mississippi River Basin – The power of the Mississippi is nearly incomprehensible.  When a large river like the Mississippi nears sea level it wanders and meanders back and forth, carving a wide floodplain, sometimes abandoning those meanders and leaving oxbow lakes.  Consequently, the Mississippi and its nearby tributaries are responsible for the expansive flat landscape that stretches from Cairo, Illinois to New Orleans, more than 200 miles wide in some places.  It is amazing to see from the air.
  

This particular trip gave me a chance to finally see the Yazoo River Basin and its unique drainage pattern.  Beginning just south of Memphis, Tennessee and continuing southward to Vicksburg, Mississippi, the Yazoo and several of its tributaries run parallel to the Mississippi but do not meet it for more than 200 miles.  This happens because of the massive amount of sediment that builds up along both rivers creating natural levees that prevent the rivers from meeting any sooner.  So, next time you travel (whether it be by train, plane or automobile), look out the window.  I guarantee you'll see some amazing things.