by Ginny Klomps

This Natural Area features a natural tunnel (or natural bridge) in Burlington limestone. In addition to the tunnel the area includes a limestone bluff, a headwaters stream and a limestone glade.

The natural tunnel was created by stream piracy when a stream branch took an undergound shortcut to Sandy Creek through a short cave. The resulting tunnel is impressive. Its entrance is about 12 feet wide and 16 feet high and narrows to about 8 feet wide and 30 feet high. The entrance is easily accessible and fairly level, but the tunnel floor then inclines steeply, terminating as a hole in a 50-foot cliff overlooking Sandy Creek. The tunnel runs southeast and photographs well in mid-morning or late afternoon.

The tunnel is only one of several interesting features to be seen here, however. Sandy Creek, which runs along the eastern boundary of the area, is a good example of a high quality headwaters stream. The creek, which flows into the North Fork of the Cuivre river, is clear with a bottom of sand and gravel. A good way to see the tunnel is to wade across the creek to a gravel bar across from where the tunnel exits the cliff. Large softshell turtles, southern leopard frogs and signs of beaver can all be seen in and along the creek. In summer rough-winged swallows dart in and out of the tunnel and swoop over the creek in search for insects. Turkey vultures patrol the area from higher in the sky.

South of the tunnel along the creek is a moist limestone bluff. This habitat supports a variety of plant species including columbine, bluebells, bloodroot, Dutchman's breeches, and several ferns. False hellebore (Veratrum woodii) grows at the base of this bluff. This plant was once considered rare, although it is actally not uncommon in Missouri.

The bluff containing the tunnel is topped by a small limestone glade. Although glades are rare in most of the Glaciated Plains Natural Division, small glades such as this are typical of the Lincoln Hills Section. This particular glade is special because upon it grows widow's cross sedum (Sedum pulchellum). Sandy Creek Glade is one of the northernmost locations for this diminutive plant in Missouri. Other plants found on the glade include red cedar, blue ash, chinquapin oak, prickly pear cactus, little bluestem grass, sideoats grama grass and shooting star.

Visitors will find this area interesting for both its geological and biological features.

SIZE: 20 acres.

DATE OF DESIGNATION: August 28, 1980.

LOCATION: In northwest Lincoln County off Highway HH.

NATURAL SIGNIFIGANCE: Natural tunnel, limestone bluff and headwaters stream of the Lincoln Hills Section, Glaciated Plains Natural Division; one of the northernmost stations for widow's cross sedum (Sedum pulchellum).

GEOLOGICAL HISTORY: Principal feature is a natural tunnel in Burlington limestone formed by stream piracy.

OWNERSHIP AND MANAGEMENT: This is a privately owned Natural Area registered with the Missouri Department of Conservation. Owned and managed by:

Bridle Spur Hunt Club

SPECIAL REGULATIONS: Prior permission to visit the area must be obtained from the owners. Hunting, fishing, and collecting of plants or animals is prohibited.

NEARBY AREAS OF INTEREST: Logan Wildlife Area and Cuivre River State Park (Pickerelweed Pond and Big Sugar Creek Natural Areas are in Cuivre River State Park).