Afoot and Afield: Atlanta. MARCUS WOOLF
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central Georgia can range from the low 50s to the mid- and upper 60s, and sunny, winter days make for great hiking. Occasionally, a polar air mass will swing through, and the northern mountains will get hit with snowfall plus temperatures well below freezing. Still, a traveler can experience relatively mild days in winter, and the lack of foliage allows views of surrounding landscape that you simply won’t get in spring, summer, and fall.
Throughout the northern and central regions, summers in Georgia are hot and humid, with highs in the 90s and lows in the 70s. The mountains can be 8 to 10 degrees cooler than lower regions in summer, but the humidity is still a factor. You’ll find fewer travelers along the trails in July and August, when it’s nice to hike next to a river, stream, or lake where you can swim to cool down.
Georgia receives moderate to heavy precipitation, about 40 to 50 inches per year, with the amount of rainfall generally even throughout the year. Rainfall amounts are higher in the upper elevations, and the mountains in the northeast can get 75 inches of precipitation in a year. When I began working on the first edition of this book in 2007, Georgia suffered severe drought, with Atlanta receiving only 31.85 inches and Athens a mere 31.51 inches. Towns such as Helen and Hiawassee in north Georgia fared better, getting 45 to 50 inches of rain. Because stream flows were unpredictable, I had to plan my backcountry travel carefully and ensure that I had sources for drinking water. In recent years, annual rainfall totals have risen, and you will likely not have to be as careful, but you should still carry an ample water supply at all times.
A final climate consideration for outdoor travel is severe weather, especially tornadoes. In north and central Georgia, a tornado can strike anytime, but the greatest activity occurs from April to June.
Geology
The area of Georgia covered in this book includes four geologic zones: Valley and Ridge in northwest Georgia, the Blue Ridge in the northeast, Piedmont in the central area of the state, and the Fall Line separating the Piedmont from the Coastal Plain.
VALLEY AND RIDGE
As its name suggests, the Valley and Ridge area in northwest Georgia is comprised of a series of ridges and valleys that generally run from northeast to southwest. In the Paleozoic Era, this land was the bed of a shallow sea, and the landscape is comprised of limestone, sandstone, shale, and coal. Near the end of the Paleozoic Era, two tectonic plates collided, and metamorphic rock was pushed up and over sedimentary stone in northwest Georgia. This process bent the land into large folds, and a ripple effect to the northeast formed the Appalachian Mountains. Over time, erosion created what we see today—long ridges covered mostly with pine and oak forest and valleys between that serve as pastureland and farm fields.
BLUE RIDGE
The north-central and northeast regions of Georgia lie within the southern boundary of the Blue Ridge zone, which extends to Virginia. Millions of years ago, sheets of the earth’s crust were compressed, thrust upward, and stacked to form the dramatic mountains ranging from 2,000 feet to nearly 5,000 feet in elevation. Here is Georgia’s high point, Brasstown Bald, and towering peaks such as Yonah Mountain. The land in the eastern portion of Georgia’s Blue Ridge is primarily comprised of igneous and metamorphic rock, such as granite and quartzite. Geologic activity in this region also formed deposits of marble, as well as the Gold Belt, which runs from the Alabama border to Lumpkin and White counties in northeast Georgia.
PIEDMONT PLATEAU
Atlanta, Athens, and the majority of Georgia’s population lie within the Piedmont zone, which runs across the belly of the state, between the Valley and Ridge and Blue Ridge zones to the north and the Coastal Plain to the south. This region is mostly comprised of rolling hills, though faults in the southwestern Piedmont created Pine Mountain, which rises dramatically amid the surrounding lowlands. The rocks in the Piedmont zone are primarily igneous and metamorphic, which have weathered to form the red clay that is known so well in the state. This region also includes igneous granite, which makes up Stone Mountain and Panola Mountain near Atlanta. Important natural resources in the Piedmont include the Chattahoochee River, which follows the ancient Brevard Fault Zone that runs from Alabama to North Carolina. The Piedmont area was once a region of thriving oak and hickory forest, but the removal of timber and farming of cotton and tobacco have left the area largely covered in pines.
FALL LINE
This geologic boundary stretching from Columbus to Augusta separates Georgia’s Piedmont and Upper Coastal Plain. It is dubbed the Fall Line because, as you move inland from the Coastal Plain, this is the first place you meet river rapids and waterfalls. Here, waterways such as the Ocmulgee River in Macon drop from the upland areas of metamorphic rock and clay soil into the lower landscape of the Coastal Plain, which is made up of sedimentary rock and sandy soil. In Georgia’s early days, the Fall Line created a natural barrier for river navigation, and goods transported on rivers in the Coastal Plain had to be off-loaded at the Fall Line and transferred to other transports to be carried upstate. This exchange led to the development of cities, such as Columbus, Macon, and Augusta, on the Fall Line.
Winding among the Rocktown boulders (Trip 12)
Forests
With more than 24 million acres of forestland, Georgia has the largest area of forest of any southern state. About half of the state’s forests are primarily pine, a third of the forestland is covered with hardwoods, and the rest is a mix of pines and hardwoods.
OAK–HICKORY FOREST
The north Georgia mountains fall into the oak–hickory forest classification. Here you will find a wide variety of oaks such as white, chestnut, red, scarlet, and black. Some of the hickory species include shagbark, bitternut, and pignut. North Georgia’s mountain slopes and stream basins are also home to hemlocks, which can grow to be 100 feet tall with trunks 4 feet in diameter. You’ll see sweet birch as well in the hardwood coves of the mountains. Moist mountain areas support black cherry as well as butternut trees, which produce a fruit with a hairy yellow-green hull. Red maples grow on the slopes and in the valleys of the mountain region (and are also common in the Piedmont). One prominent tree in the region is the sourwood, with trunks that sometimes bend at great angles. Older sourwood trees have bark that resembles alligator skin with deep furrows.
Whether you’re hiking in the Valley and Ridge, Blue Ridge, or Piedmont regions, you will notice a change in tree types in moist coves and along stream banks. River birch is common along streams and is identified by bark that peels off in curls. This is also the habitat for blue beech (20 to 30 feet high), as well as the much taller and often-seen American beech. This tree can be 80 feet high and has easily recognizable smooth, gray bark. Areas with moist soil in these parts of the state give life to Fraser magnolias, which have smooth, gray-brown bark and long, broad leaves that are green and glossy. In such regions, yellow poplars are common and grow to more than 100 feet in height. Yellow poplars have smooth bark that appears gray on older trees. In bottomlands and along stream banks, American sycamores can also be found.
A clear view through the hardwoods on the Miller Trek Trail, Brasstown Valley Resort (Trip 39)
PINES
A variety of pines also live throughout the state’s northern and central regions. One type, the eastern white pine, tends to thrive in valleys and coves and has needles in clusters of five ranging from 3 to 5 inches long. In the upper reaches of the state, as well as the Piedmont, shortleaf pines can grow to be 100 feet tall. The yellow-green needles of the shortleaf pine are 3 to 5 inches long and grow in clusters of three. Pitch pines live mostly on northeast Georgia’s high, dry ridges. They usually grow to about 50 feet in height, and in the early days of Georgia’s settlement they were used to produce turpentine and charcoal.
The mountains and upper Piedmont support Virginia pines, which usually only reach about 40 feet high and are shorter than other pines.