Back to Stop #6: Johnson’s Shut-Ins Web PageThe swift waters of the East Fork Black River flow through a canyonlike gorge called a "shut-in", in the 2,490 acre Johnson's Shut-Ins State Park. The blue-gray, steel-hard volcanic rocks that formed the shut-ins are nearly 1.5 billion years old.
These rocks were formed when violent volcanic eruptions exploded with clouds of ash, debris and turbulent gases. The material avalanched down towering volcanic mountains, spread out, layer upon layer, and cooled to form the rocks exposed today at Johnson's Shut-Ins State Park.
About 500 million years ago, shallow inland seas covered the already ancient and eroded volcanic mountains. These seas buried the volcanic igneous rock under hundreds of feet of sedimentary rocks such as dolomite, limestone, sandstone and shale.
Following major uplifts of the entire Ozark region about 250 million years ago, the seas retreated. The rain and wind eroded away great volumes of the sedimentary rock. As river valleys deepened, streams sliced down through the soft sedimentary rock layers, and some encountered buried igneous rock below. As the streams carved downward, certain sections were caught in igneous rock saddles, or low places between buried igneous hills. Now trapped between these hills, the water churned over the resistant rock, and erosion occurred most rapidly along the rock's weaker fracture zones. Swirling over and between the rocks, the river scoured and carved potholes, chutes and spectacular canyonlike gorges. Johnson's Shut-Ins is Missouri's most outstanding example.
The park is located in the scenic St. Francois Mountains, and the area surrounding the park retains the wilderness qualities of presettlement times. Outstanding natural features characteristic of these mountains and found in the park include igneous "rock glaciers", igneous glades, extensive gravel washes, fens, and forests of oak, hickory and shortleaf pine. Today, these outstanding features are preserved in Johnson's Shut-Ins State Park by the Missouri Department of Natural Resources.
Canyonlike shut-ins, talus slopes, and open glades are the principal features of Johnson's Shut-Ins Natural Area. A short walk from the parking lot will enable visitors to see the rhyolitic rocks that originated from volcanic eruptions more than 1.5 billion years ago. The flow of water from the East Fork Black River along fractures in the ancient rock has carved the shut-ins, chutes, and the nearly vertical gorge of Johnson's Shut-Ins.
The forest on the slopes along the shut-ins developed on accumulations of decomposed vegetation and weathered igneous rocks and boulders that fell from the hills above. This rocky talus slope, sometimes called "rock glaciers", supports many ferns and a mixed hardwood and pine forest.
Glades, Missouri's version of desert, also occur in the natural area. These rocky, barren openings in the forest support drought-adapted plants commonly found in the deserts of the southwestern United States, including prickly pear cactus, flame flower, and pineweed. Scorpions and the rare eastern collared lizard, known as the mountain boomer, reside on the glades. This large lizard rises to an upright position and run on its hind legs when distrubed.
Located in the St. Francois Mountians, the 1,110-acre East Fork Wild Area provides outstanding recreational opportunities in a wilderness setting. The major portion of the park's geological and biological diversity are protected in the wild area.
More than 900 species of plants have been recorded in the park, and many of these, including several rare plants and the largest Virginia witch hazel in the state, can be found in the wild area.
Natural communities found in the area range from bottomland woods to upland ridges, bluffs, and wet meadows. A mixed forest of oak, hickory, and shortleaf pine covers the mostly rocky soil. Glades are common and provide open scenic vistas. Bald eagles occasionally have been sighted along the river. Several trails through this remote wild area offer visitors opportunities for hiking, backpacking, bird watching, nature study, and photography.
Johnson's Shut-Ins State Park has 52 campsites, half of which have electrical hookups. Each site is limited to one family or group. A gate at the entrance to the campground helps ensure that only registered campers enter.
Half of the campsites are reservable two weeks in advance on a first-come, first-served basis for a maximum continuous stay of 15 days. Facilitites in the camping area include modern restrooms, hot showers, a dumping station, and coin-operated laundry equipment. A nominal daily camping fee will be collected by park personnel. Camping is available year-round; however, the water in the campground is turned off from Nov. 1 through April 1.
The shut-ins provide a water-filled playground among the smooth volcanic rocks. The East Fork Black River offers fishermen the opportunity to hook smallmouth and largemouth bass, bluegill, and goggle eye.
The park also serves as an important trail head for the Taum Sauk section of the Ozark Trail. East of the park, the Taum Sauk section of the trail leads hikers to Proffit Mountain, Mina Sauk Falls, the highest waterfall in Missouri, and on to the 1,772-foot-high Taum Sauk Mountain, the highest point in the state. The Ozark Trail also leads north and west from the park into the Bell Mountain Wilderness Area in Mark Twain National Forest. The Ozark Trail will someday stretch continuously from the St. Louis area to the Arkansas border.
Backpack camping is permitted along the Taum Sauk section unless otherwise posted. Campers must choose a site at least 100 feet from the trail and 200 feet from any major public-use area, and one-fourth mile from the trail entry/exit point.
Please stay on the trails and do not take shortcuts. The trails have been laid out to minimize destruction of vegetation and to prevent erosion.
The 46 picnic sites located throughout the park are ideal for family and group picnicking. A shelter house in the picnic area may be reserved. Restrooms in the campground and picnic areas are designated to be accessible by wheelchairs.
The shut-ins are one of Missouri's most interesting features, but caution is needed to enjoy them safely.
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