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Natural Antiques

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Published on: Jul. 2, 1998

Last revision: Nov. 1, 2010

Anyone who likes antiques or other "old stuff" and also has a yearning to visit the wild outdoors should investigate a natural antique: the St. Francois Mountains Natural Area. This natural area, including parts of Ketcherside Mountain Conservation Area and Taum Sauk Mountain and Johnson Shut in's state parks, is part of the oldest landscape in Missouri and one of the oldest in the Midwest.

Located in Reynolds and Iron counties, these rugged mountains, with their unique geologic formations and plant and animal communities, are prize antiques in Missouri's natural world.

The St. Francois Mountains Natural Area is one of the most recently designated state natural areas recommended by the Missouri Natural Areas Committee (see sidebar on page 9). This designation protects and recognizes one of the best examples in the state of a large, wild igneous (volcanic) landscape that includes forests, savannas, open glades, an outstanding Ozark creek, the largest waterfall in the state and rare plants and animals. To top it all off, these features are located on and near the highest mountain in the state, which reaches 1,772 feet in elevation.

The formation of the St. Francois Mountains started over a billion years ago in the late Precambrian Geologic Era, long before the notion of dinosaurs, primitive amphibians, trees and trilobites. Great explosions of volcanic ash and gases blasted through the earth's crust. Ash flows blanketed miles of earth. Periods of uplifting, folding and deformation of the earth's surface were followed by more eruptions and deposition of volcanic materials.

In no other natural setting is the geologic story of these mountains so clearly presented. Rock exposures in today's natural area provide evidence of past volcanic activities and allow an observer to view the geologic history of this most ancient part of the Ozarks. At least six different igneous rock formations are exposed within the area.

The formations mostly are composed of rhyolite porphyry-brittle rock that formed from over-land ash flow that cooled and solidified rapidly, forming fine grains. In contrast to rhyolite porphyry, granite, which is found infrequently on the area (but is important in the overall St. Francois Mountain region), formed from liquid molten magma deposited below the ground surface. It cooled and solidified slowly while still underground, forming coarse grains with large crystals of feldspar (a mineral group of silicates of aluminum and potassium, sodium or calcium) and quartz.

Basalt is visible as black bands of rock throughout the rhyolite exposures. Basalt is the result of molten magma injected by underground explosions up into vertical cracks of the rhyolite over several hundred million years. Each geologic layer forms distinct units, with colors varying from violet to red to maroon to gray and thicknesses from 25 to over 900 meters.

As geologic time passed and the volcanic activity ceased, weathering and erosion removed the existing topography and carved the area into a hills and valley landscape. Topographic relief was still greater than today-with differences of more than 2,000 feet from mountain top to valley floor. Today that distance is less than 1,000 feet.

During the next geologic era, the Paleozoic, ancient rivers and seas deposited limestones and dolomites, sandstones and shales initially in the valleys and later, higher up the side slopes, burying the Precambrian volcanic landform. Remainders of these sedimentary rock layers still are exposed on the lower slopes of the hills and in the valleys. This region, along with the rest of the Ozarks, experienced more uplifts during the end of the Paleozoic Era. The upper elevations of the old Precambrian surface were resurrected, as soils and sedimentary layers were eroded away.

The erosion continues today, but within the natural area boundaries, we are able to view the remaining ancient topographical surface much like it appeared millions of years ago.

If these antique rocks could talk, they could clear up the various tales about the region. The legends naming the Taum Sauk Mountain and the Devil's tollgate and explaining the formation of Missouri's highest waterfall, Mina Sauk Falls, all involve an Indian tribe called the Piankashaw.

European settlers forced the tribe out of the east, and they passed through Missouri on their way to the Indian territory of Oklahoma.

Though there are no facts to support the legend, it is said that Taum Sauk, the chief of the tribe, had a daughter, Mina, who was in love with a warrior from the hostile Osage tribe. The falls were formed when Mina threw herself off the mountain to her death after her people had killed her Osage lover in a similar manner. The Great Spirit sent a bolt of lightning which split the mountain top, and a stream of water flowed over the ledges, washing away the blood of the lovers. You can still see blood-red flowers, known as Indian Pinks, that grow along the banks of the stream each spring.

The rocks can tell us something about the different natural communities that grow on and around them. Certain plant and animal communities evolve to fit an area's geology, so by knowing what geology is prominent in a region, biologists can expect to find certain specific natural communities there.

In the St. Francois Mountains, on the rockiest, most exposed sites, glade communities persist. Glades are dominated by herbaceous plants-grasses and forbs-adapted to hot, dry conditions. You may see glade onion blooming purple and cream wild indigo in the spring, followed by the endangered Mead's milkweed, which displays a green flower in early summer. The St. Francois Mountain Natural Area is home to one of the largest populations in the world of this rare milkweed, which also grows on prairies in southwest and north Missouri.

Blazing stars, pencil flowers and coreopsis dress the glade openings throughout the summer. In autumn, grasses, such as little bluestem, big bluestem, Indian grass and various panic grasses, put on their yellow and orange foliage display.

Collared lizards, just as colorful as the wildflowers, sun themselves on the exposed rhyolite outcrops. These openings provide impressive vistas of wildness. Wildcat Mountain, Church Mountain, Wiemer Hill and Proffit Mountain-all appear void of human intervention.

Savannas surround the glades. Dwarfed blackjack and post oak trees with wide spreading branches barely surpass the height of the igneous boulders in this dry, rocky ecosystem. Short-leaf pine is distributed unevenly throughout the savannas and forests but is not as common as it used to be, according to historic accounts of the area. Poverty grass, wild quinine, lowbush blueberry and farkleberry are common herbs.

Forest natural communities occupy most of the natural area acreage. Forest communities range from dry on the ridges and side slopes to mesic (moist) along Taum Sauk Creek. White oaks, red oaks, post oaks, mockernut hickories, black gum and dogwoods are only a few of the tree species growing on the mountains. The boulder-filled Taum Sauk Creek winds through the forest, past the Devil's tollgate, and is fringed with sycamores, blue beech, ninebark, vernal witch hazel and a rare shrub, the winterberry.

Some 400 plant species live in the natural area. In addition, biologists have seen at least 48 animals, including reptiles, birds, mammals, fish and crayfish. No one knows how many lichens, insects or nematodes are out there to be discovered.

Although these communities may seem like untouched wilderness to the untrained eye, many signs of past human intervention exist. Fence lines are still marked by oaks with bulging rings around their trunks where the tree cambium has grown over rotten fence wire, and many double-trunked trees remain from past logging. Certain plant species that increase under disturbances, such as heavy grazing, are scattered throughout the area, including buckbrush, non-native lespedezas, mullein and Queen Anne's lace.

Like the geologic features, the living natural communities of the St. Francois Mountain Natural Area may, too, be considered antiques (they are only thousands of years old, instead of billions). And like many antiques that need to be restored, the living natural landscapes also need to be revitalized. It may be easy to restore parts of an antique chair-reglue a leg or replace a seat cover-and similarly, certain species or a certain landscape structure may be restored with relatively little difficulty.

But all of the natural parts are not even known. Species and processes are still being discovered, so it is hard to completely "restore" an area since we don't really know what all the components of the original community were. Restoration efforts include using fire, as was done in the past, to bring back the large expanses of grassy open woods and glades described by land surveyors in the 1820s. Prescribed fire may renovate certain areas fairly rapidly, but more disturbed areas may take decades or longer. As more knowledge is acquired, we may undertake new restoration methods. What took thousands of years for nature to form surely will take as long for humans to understand and rebuild.

Missouri's Natural Areas

The Missouri Natural Areas Committee works to protect and actively manage the best examples of all remaining natural communities and geologic features in Missouri as designated natural areas. The committee consists of representatives of the Missouri Department of Natural Resources, Mark Twain National Forest, Ozark National Scenic Riverways and Missouri Department of Conservation.

These agencies have been cooperating for more than 20 years to identify and protect Missouri's unique and common natural features. There are currently 168 natural areas with 45,000 acres designated in 74 counties. Many natural areas have more than one ownership within the designated boundaries, like the St. Francois Mountain Natural Area. Each agency is responsible only for the management of the portion that they own, although management actions may be suggested by the Missouri Natural Areas Committee for the entire designated area.

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