“Archaeology is almost everywhere,” said Ben Hoksbergen, Redstone Arsenal Installation Archaeologist, to a crowd of around 20 people gathered at the newly-built pavilion at the Land Trust of North Alabama Rainbow Mountain trailhead. Ben was our leader on a guided hike on parts of the Rainbow Mountain Loop trail and the Spring trail, and he’s one of the experts recruited by the Land Trust to help interpret the natural and cultural resources in a series of guided hikes on their preserves.
Though we’ve hiked and done trail maintenance on Rainbow Mountain a number of times, this outing would give us a new perspective. Ben explained that the geology of the first part of our hike, near the playground, dated to 325 million years ago. This layer of Hartselle sandstone, formed at the bottom of an ancient sea, persists up on the mountain since this particular sandstone is relatively hard and doesn’t erode as quickly as the limestone found pretty much all over the area. This layer of sandstone is also known for harboring pockets of oil, though of the tar sand variety, so it’s not economically feasible to process it.
We walked along the top of Rainbow Mountain, where eagle-eyed Ben spotted a small piece of blue flint debitage on the surface. Debitage is the flaked-off pieces left as debris during the formation of a stone tool. He explained how stress lines on the chip can indicate that the flake was struck from a larger piece, then carefully noted the location of the item on a GPS. As far as prehistoric archaeology goes, Rainbow Mountain is not exactly a hotbed. Its relatively high altitude and lack of major water sources didn’t make for good settlement sites, though the microclimate at the top of the mountain could be a source of certain medicinal and edible plants (such as prickly pear cactus, which we spotted off the trail).
So we didn’t have high hopes of digging up another Moundville duck bowl, but Ben had a screen and a shovel, and he proceeded to perform some shovel tests in three small rock shelters along the top of the mountain. It’s time to insert the important disclaimer that digging for archaeological artifacts is something best left to professionals. If you’re doing it on private lands, you get into tricky questions of legal ownership, and more to the point, you’re also likely to get into the path of an irate owner with a shotgun. If you’re doing it on public lands, you’re very likely breaking the law, and yes, people get caught, fined, and/or jailed all the time. A 2010 story on al.com contains the tidbit that at least two dozen people per year are cited in the Wheeler National Wildlife Refuge for digging for artifacts.
Fortunately, we had a professional on hand for our hike, and he quickly sorted through the lumps of dirt and rock to find…exactly no indications of early inhabitants. That’s not to say there wasn’t anything interesting, though — he found a few fossils, including one that shows part of some plant, and some archimedes fossils that look like corkscrews. It’s pretty cool to hold in your hand an imprint of an aquatic animal that lived 250-350 million years ago. He also found bits of modern glass, a modern button, and in two locations, a .22 caliber shell.
The rocks on the top of the mountain are Monteagle limestone, heavily eroded along channels in the rock, which is pretty much what you’ll find on most ridgetops in the area. As we descended down the east end of the Rainbow Mountain Loop trail and headed north, Ben pointed out knobs of chert and more fossils found in larger rocks. Chert is often used for stone tools and points, and native Americans frequently quarried rich veins of chert and camped nearby. The quality of the chert on Rainbow Mountain isn’t that great, so there aren’t likely any quarries there. Going back to the geology for a moment, chert is a sedimentary rock usually found in a deeper layer than the sandstone and limestone layers, but since sandstone weathers more quickly and limestone dissolves in our mildly acidic rain, chert has a way of working to the surface.
Our hike took us to the east end of the Spring trail, so named because it follows a small creek that originates from a spring about halfway up the trail. This is a fairly steep little trail, but Ben wanted to point out that when looking for potential archaeological sites, water sources can be an important indicator. Also, this trail has several introduced species — notably, multiflora rose, nandina, Chinese privet, and vinca. Though those non-native invasive plants are ubiquitous around here, in some cases they may be been deliberately planted for ornamental purposes. The topography of this particular trail didn’t offer any good locations for a house, but it does have a small entrance to a cave that could lead to something much larger than we were prepared to tackle. It’s interesting to note that we skirted one sinkhole, and small caves and fissures point to the likelihood of one or more pit caves under Rainbow Mountain.
We made our way back to the pavilion, having spent a very enjoyable two hours covering about 1.5 miles. This wasn’t a hike where the objective was to get from point to point. Instead, it gave us insight into how an archaeologist views the terrain when out walking about. I was struck by how helpful it is to have knowledge in geology and botany when evaluating potential sites of archaeological interest.
Guided hikes might not be for everyone. With any group of hikers, you’re going to run into the inevitable problem of not everyone hiking at the same pace, and those toward the end of the group may miss some of the narration. And if solitude is your thing, this type of hike won’t appeal to you. However, we’ve been to a few of these Land Trust guided hikes, such as the history hike to Trough Springs and a forest ecology hike on Wade Mountain. The Land Trust does a splendid job of finding interesting, enthusiastic people to enrich the outdoor experience by providing insight and context.
There’s a series of guided hikes every spring and fall, and the last one of the fall season is the annual Thanksgiving Day hike, held this year on November 26 at 9 am. This hike starts at the Bankhead parking lot on Monte Sano and heads mostly downhill on the Alms House trail to Three Caves, a former limestone quarry normally open only during special events. The hike, like all Land Trust guided hikes, is free. If you’re looking for a place to whip up an appetite, or perhaps put in a caloric down payment on your Thanksgiving feast, it’s a two mile hike one-way, with an optional shuttle back up to the parking lot (or you can just retrace your route to earn yourself another piece of pie). Though we’re at the end of the fall hike series, keep an eye on the Land Trust’s website for information on the spring hike series. Or better yet, join the Land Trust and find out about these events in advance, along with invitations to members-only hikes.