FLORA AND FAUNA
By JEFF DURBIN
September 30, 1999
Note: This article appeared in Vox, the Missourian's weekly magazine insert. The scanned original page includes illustrations. Full (and more readable) text follows.
The history of the osage-orange tree tells part of the history of the American frontier. Native Americans used the wood--called bois d'arc by French trappers, bodark by some Missourians today--for archery bows. Saplings were strong and flexible, and strung with bison sinew they made a formidable hunting weapon. Osage-orange provided a very different use to the settlers who took over Indian lands. Because there were few trees on the Plains, homesteaders planted thorny osage-orange hedges in the years before the invention of barbed wire (1874), and pruned them for slow growth. "Hedge," in fact, is another name for the tree. The hedge-fences made growing crops and keeping livestock possible. Even some early streets were paved with hard and heavy blocks of osage-orange. Untended osage-orange hedges have now become rows of tall trees all over the old frontier. The fruit vaguely resembles a highly wrinkled grapefruit. Though inedible for humans, it's a squirrel and pack rat favorite. Read the classic "PrairyErth" by local writer William Least Heat-Moon for a more elegant story of osage-orange (pages 279-287). Osage-orange trees do best on moist bottomlands, but in general you simply find them here or there in Missouri forests.
Halloween, complete with bats, goblins, and ghosts, is on the way, but in Missouri most bats will soon leave for warmer areas. Through the summer and into September, bats take wing precisely at dusk and hone in on insects with echolocation, a bat-sonar consisting of 30-60 squeaks per second. Here in Columbia, we see them sharing the streetlit evenings with nighthawks, pursuing moths, mosquitoes, and other insects. South of the city, endangered gray bats nightly pour out of Devil's Icebox in Rock Bridge Memorial State Park, and that's why the cave is closed from April to September. Only mature females roost in the cave, and they don't tolerate human disturbance well. About 10,000 raise young during the summer, generally feeding at the Missouri River, eight miles away, consuming about 30 percent of their body weight in insects each night. At the end of summer, the females and males (which use other local caves), join up and migrate to southern Missouri, where they hibernate. Devil's Icebox is actually a cavern system through which an underground river flows, fed by rainwater draining through sinkholes and a "swallow hole" in Bonne Femme Creek--therefore the sensitivity of the cave to chemicals, leaking septic tanks or trash dumps on the surface above. Other bats also use Devil's Icebox at different seasons: Indiana, eastern pipistrelle, and little and big brown bats. Now that Devil's Icebox is open again, call the park at 449-7402 for a permit and reservation, which includes a guide and equipment.
Oak species dominate many of Missouri's forests. Oak-hickory forest covers much of the Ozarks and central Missouri. The list of oaks is long and impressive, with about 20 species in the state, plus hybrids. Rather than pore over species differences in an armchair, take a tree walk on the MU campus with a booklet called "Tree Trails" (available in the lobby of Reynolds Alumni Center). Nine native Missouri oaks are neatly labeled, along with an imposing English oak behind Jesse Hall. Then go to the woods for the real thing. The Missouri Department of Conservation also has a free booklet on trees. White oaks are the biggest and oldest oaks in these parts, and produce the most valuable hardwood in Missouri and the United States. Huge-leaved, fire-resistant bur oaks grew in prairie savannas. These oaks resist fire because of thick bark, rot-resistance after scarring, and the ability of acorns to germinate well in burned soil. The state's largest bur oak, 89 inches in diameter, is located near McBaine, down Route K from Columbia. Oak acorns are essential in the diets of squirrels, raccoons, quail, turkey and deer. Real oak aficionados will find it helpful to divide oaks into white oak and red oak groups: that will make leaves and acorns easier to tell apart. And advanced buffs should think about the mechanics of forest succession: will an oak forest always be an oak forest? It happens that we live in an age of oaks. Oaks now dominate because they resisted fire for millennia, and were primed to take over when settlement came, fire was suppressed, and forests cut. The oak closed in to form forests, but some future mid-Missouri forests may be taken over by sugar maple. Oaks will still dominate harsher sites, however.
Your chance to see bald eagles comes in late fall and winter at Eagle Bluffs Conservation Area, along the Missouri River six miles southwest of Columbia. Birdwatching can be brutally difficult, but if you keep your eyes on the sky you can't miss the seven-foot eagle wingspan (compared to wingspans of about four feet for hawks). Young balds may look like golden eagles, lacking white head feathers--those come at age four or five. Though several bald eagles are year-round Eagle Bluffs residents, in December about 10-12 will congregate from parts unknown, and what they find at Eagle Bluffs is unfrozen ponds and rivers and a supply of fish carcasses. Truth be told, our national bird is more scavenger than classic bird of prey, though waterfowl and small mammals are at-risk. Recently, breeding pairs have nested high in trees in prominent assemblages of sticks, but without success. Possibly they were young birds still learning parenting skills. An outing to see bald eagles is a good excuse to see the rest of Eagle Bluffs. It's much more spectacular if you bring binoculars or a spotting scope. Some ducks migrate through during the first couple weeks of November, others winter over-it all depends on the weather. In the adjacent bottomland forest, look for turkeys, deer, or loud, huge, hammerheaded pileated woodpeckers. Lucky visitors could see a peregrine falcon, white pelicans, or see and hear a trumpeter swan or two. The bald eagle made national headlines this summer when its recovery during the last several decades was considered successful enough for removal from the Endangered Species List. It is still strictly protected by other laws. If you need your fix of large raptors right away, any trip to Columbia's Grindstone or Capen parks will offer turkey vultures.
You know you're got a heck of a tree when it can be identified with aerial photographs. From above, the peeling white bark of large American sycamores marks the course of streams and rivers in Missouri. They make good urban trees, too, growing fast and not minding dirty air. Older sycamores are often hollow, and make great dens for raccoons or squirrels. Occasionally for humans, too: according to Flora of West Virginia, two gentlemen named John and Samuel Pringle lived in a hollow sycamore in that state from 1764 to 1768. Whether they shared the tree with other small mammals is not known. The sycamore is one of the largest eastern trees, and the record Missouri sycamore is a whopping 7 1/2 feet in diameter. Golf-ball-sized fruits hang on sycamores through winter, dropping seeds in spring that disperse by water and wind. You can see sycamores throughout Boone County, wherever there's flowing water.
Perhaps it's the long, rat-like tail or narrow snout, but the shambling opossum could use more admirers. Possums have more qualities than first meet the eye, such as a stomach pouch in which females raise pea-sized young for two months, dexterous hands and feet with opposable toes, and a versatile tail that can wrap around a branch for hang-time, store body fat in winter, or carry leaves for den bedding. And who could not applaud possum playacting? Possums will sometimes feign death when under attack, at the same time emitting unpleasant and discouraging liquids for the attacker to contemplate. But don't approach them to test this: possums can also decide to play fierce, growling and biting hard. With their nocturnal, omnivorous ways, possums thrive in cities as well as woods. Adaptability is the key: crickets, lizards, fruit, eggs, dead animals, are all fair meal for a possum. Crossing streets and country roads pose problems, however. You don't need to collect roadkill statistics to know that possums have not adapted to automobiles.
Big bluestem is the marquee species of the tallgrass prairie. So many pioneer accounts refer to bluestem-dominated prairie as a "sea of grass" that it has become a cliche. Big bluestem grows three to six feet high, sometimes nine. Bluestem roots descend at least as far, allowing it (as well as other prairie grasses) to withstand drought, fire and grazing. In pre-1800 Missouri, tallgrass grew north of a line drawn from Springfield to Columbia to St. Louis. Tallgrass prairie soils are so rich that they precisely coincide with the best farmland in the world. Nowadays big bluestem is seen occasionally along roadsides, fencelines or train tracks, and in restored and virgin prairies. Locally, look for it at MU's Tucker Prairie, 20 miles east of Columbia on Interstate 70, or in two rest areas along I-70 near Boonville. The best clue to identification is big bluestem's nickname, turkey foot, which is the shape of the seed head. And stems indeed turn bluish or purple. Big bluestem mainly spreads by underground stems, only rarely by reseeding: it is said that some prairie botanists have never seen a bluestem seedling. In other words, many neighboring plants are clones with identical DNA, just as aspen trees in a forest tend to be clones. Big bluestem makes superb hay and is being rediscovered for raising livestock. Footnote: the best-preserved tallgrass prairie is in the Flint Hills of Kansas, about a five-hour drive from Columbia.
Missouri drivers know how hard it is to avoid turtles crossing roads and highways every June. It's turtle wanderlust with a reason: female box, painted and snapping turtles are on a single-minded quest for well-drained sites to lay their eggs. By now most eggs have hatched, and the young have completed their mission back to their mothers' home ponds, though some hatchlings may remain in the underground nest and emerge in spring. The hatchlings home in on the mother's pond by a combination of techniques, though this is not well-understood. Perhaps they use polarized light as a compass, or follow chemical cues. The menfolk, meanwhile, await the day hormones kick in that will send them on the move in search of mates. That is happening now, so driver beware. Both drivers and turtles would appreciate "toad tunnels" to funnel them under roads. They're popular in England and parts of California and New England, but Missouri has none. Turtles are eclectic gourmets: pond turtles eat aquatic plants, snails, crayfish, insects, sometimes fish. The terrestrial box turtles prefer insects, earthworms, berries, and plant shoots. As winter approaches, the turtles can no longer maintain their body heat, so they do the sensible thing and hunker down, metabolism slowed way down, absorbing through their cloaca the small amount of oxygen they need. Box turtles burrow into moist, loose soil to spend the winter, while pond species such as painted and snapping turtles like to bunch up under tree root masses where there is some moving water to provide them oxygen. The females store sperm from fall mating until they ovulate the following spring. An excellent guide, "Missouri's Turtles," is available for free from the Missouri Department of Conservation.