A Prairie in the Swamp

By A.J. Hendershott | June 2, 2004
From Missouri Conservationist: Jun 2004

Southeast Missouri receives more rain than any other part of the state, but it also harbors the rarest of dry habitats--sand prairies. These unique prairies are a major link to geologic history and are a major influence on the cultural history of the region.

Missouri's sand prairies are dry islands in a land of swamps. To understand how they came to be, you have to look back through Missouri's geologic history. Much of Missouri's lowlands were once inundated by a shallow gulf. The Ohio River emptied into that gulf, dumping large volumes of sand.

When the glaciers that inched across North America melted, they released enormous volumes of water that flowed down what is now the Mississippi River and its tributaries. The relentless current eroded sand plains that had long before been deposited by the Ohio River. When the super floods receded, only two long sandy ridges remained.

One of these sand ridges is called the Sikeston Sand Ridge. It runs north and south from Benton Hills to the town of New Madrid. Interstate 55 runs along this ridge. The other ridge, named for Malden, Missouri, begins south of Crowley's Ridge and runs down through Malden into Arkansas.

Factors influencing dry conditions include elevation, heat and fire. Because they are 10 to 20 feet above the surrounding land, the sand ridges allow water to rapidly percolate down into the ground water. Although the sand is mixed with some soil particles, it drains much faster than surrounding soils. This draining enhances dry conditions favorable for prairie formation. Heat, provided by sunlight, also dries sand ridges.

Fast drainage and evaporation make sand ridges a challenging environment where only drought-tolerant plants can survive.

Periodic fires also help shape sand prairies. These fires remove dead leaf litter and color the soil black. Darkened sand heats up faster and stays warm longer than lightcolored sand. Fires also improve growing conditions by removing dead grass and wildflower leaves and releasing the nutrients from dead plants into the sand. This process would take months and even years under passive decomposition.

Historically, fire burned the sand prairies every five to eight years, killing sprouting oak trees such as blackjack or post oaks.

Another challenging factor facing sand prairie life is rapid heating and cooling. Just like deserts, sand prairies heat and cool quickly. These rapid and dramatic temperature changes can make life impossible for plants not adapted to these conditions.

Unique plants live on sand prairies, including prickly pear cactus, butterfly pea, puccoon, clasping milkweed and creeping St. John's wort. While these plants are noteworthy, the grasses and sedges are the real stars of the sand prairies. One distinctive grass is the dominant splitbeard bluestem. The split-beard is a warm-season grass well suited for sandy conditions. Its silvery seed heads dominate the sand prairie landscape.

Perennial plants of sand prairies tend to have narrow leaves and tiny hairs to limit water loss. These plants also have deep roots to access water, and they grow in tufts to reduce exposure to winds that may dry them out. Annual plants borne from seeds have slender leaves, as well, and have few branches on their stem to prevent water loss. They also have fibrous roots that maximize water collection when water is available.

This natural community also is hard on animals, but some animals manage to cope. Two frogs that have adapted well to sand prairies are the Illinois chorus frog and eastern spadefoot. Both spend months burrowing and feeding underground. They only come out to breed. Their eggs hatch faster, and their tadpoles metamorphose faster than those of other frogs. These adaptations help them take advantage of the short life of sand prairie pools. They are rarely seen and are more easily detected by their calls in breeding season.

Another animal more easily heard than seen is the northern mole cricket. Mole crickets live on wet swales, pond banks, grasslands or forested areas dotting the sandy ridges. A close relative, the prairie mole cricket, used to live on sand prairies. Like northern mole crickets, they burrowed about, eating roots of prairie plants. This prairie cricket sings from a hole in the ground. The hole functions as an amplifier, making the call louder. Due to habitat destruction, the prairie mole cricket is believed to be extirpated from southeast Missouri. It has not been recorded here since 1971.

Huge herds of bison once roamed all over the southeast region. Although they roamed the swamps eating giant cane, the sand prairies were probably a regular haunt. Elk were common on these prairies and doubtless fed many settlers and explorers. Thomas Beckwith, in his book on the settlement and settlers of Mississippi County, opined that both of these creatures were gone from Mississippi County by 1860.

A wide variety of upland game animals such as bobwhite quail, mourning doves, white-tailed deer and cottontail rabbits also use these sandy meadows. Joining them are a variety of grassland songbirds, including rough-winged swallows, bluebirds, savanna sparrows, swamp sparrows, dickcissels, lapland longspurs and meadowlarks. Racerunner lizards and fence lizards also thrive on the sandy grasslands. Because there is now less prairie habitat for these animals to use, their numbers are lower than they could be. Habitat loss not only reduces population sizes, but also it also negatively impacts genetic diversity.

At one time there was a considerable amount of prairie in southeast Missouri. Dr. Walter Schroeder, lecturer at the University of Missouri, reviewed old surveyor notes of the entire state looking for descriptions of prairie. He found conservative estimates of 60 square miles of sand prairie in southeast Missouri. By the time surveyors did their work, he noted, many sections of the sand ridges were already settled. This means that the prairie was already converted to farm fields, and fires were suppressed to protect barns, homes, fences and livestock and to keep families safe. Without natural fires, trees turned much of the sand prairies into scrubby forest. In fact, before European settlement, as much as 150 to 175 square miles of prairie may have occupied the sand ridges.

Many of the towns in the Bootheel that aren't on Crowley's Ridge were founded on sand ridges. Booming towns needed land to prosper, and tallgrass sand prairies were the first to be converted to agriculture. Big bluestem and switch grass were major components of these grasslands. These grasses benefit from high organic content in the sand and moderate moisture.

Next in line were the sandy areas with less organic potential and shorter grass. Today short grass prairies remain only on the driest and sandiest locations.

The sand prairies were the sites of major travel lanes north and south. Living on the sand ridge also gave people an opportunity to live on a dry site that offered them a staging ground to access the swamps. Traveling east and west across the swamps was difficult. Pole roads made of cypress poles were built to facilitate travel between the sand ridges. The town of Portageville is one such town from where merchants portaged goods across the pole road to the Malden sand ridge.

Malden Ridge was once the site of the Grand-west- Rosebriar prairies. They stretched north from Kennett through Malden and into Bernie. Sand prairies were less abundant on the Malden Ridge, but those that existed were similar to grasslands found to the east. Higher organic content in the sand probably allowed more moisture to be retained, contributing to better tree growth. Not surprising, agricultural performance on that land was better, too.

The irony of a prairie in the middle of a swamp carried over to place names in southeast Missouri. The most notable is the town of East Prairie. It was named because it was the prairie east of the other prairies found on the Sikeston ridge. Many of the names are now forgotten, but a few residents still recall that the town of Charleston was once known as Matthew's Prairie. A few folks still remember Long Prairie, yet another grassland south of Sikeston.

The whole Sikeston Ridge was considered to be one large prairie by early explorers such as John Breckinenridge. Surveyors called this grouping of grasslands Big Prairie, while some settlers called it Grand Prairie. John James Audubon recorded a visit to the "Little Prairie of southeast Missouri." The particular section he visited was south of East Prairie. This is where he viewed and created his first painting of a Bald Eagle. Perhaps it is no coincidence that East Prairie High School's mascot is the eagle.

Today, less than perhaps 1 percent of the original sand prairies remain, and even this small area is threatened by development. Many plants and animals requiring sand prairie habitat are of major conservation concern. No sand prairies are publicly owned. Landowners wanting to restore or conserve sand prairie remnants on their property can contact their nearest Conservation Department office.

This Issue's Staff

Editor - Tom Cwynar
Managing Editor - Bryan Hendricks
Art Director - Ara Clark
Artist - Dave Besenger
Artist - Mark Raithel
Photographer - Jim Rathert
Photographer - Cliff White
Staff Writer - Jim Low
Staff Writer - Joan McKee
Circulation - Laura Scheuler