Canoe a Missouri stream and experience a variety of sounds, smells and sights. Around each watery bend there’s a chance of a calm breeze alive with newly hatched mayflies or migrating monarchs, the melody of a vacationing male prothonotary warbler in the willows or some of the most often encountered riparian sights—cliffs. Whether sandstone, dolomite, limestone, igneous or chert, these jaunting rock faces provide ideal communities for a variety of animals and plants.
Plants living in cliff environments are hardy individuals that carve out a niche of their own within the rocky cracks and crevices. Relying upon the stone-splitting action of seasonal freezing and thawing, roots descend into thin, shallow soils seeking a firm hold. Some, such as tiny ferns and mosses, display mere sprigs of greenery. Others create a splash of vibrant color here and there or simply hang, like dangling jewelry, as in the case of the wild columbine.
Mosses and lichens are adapted to ledges and often appear as carpet-like mats upon undisturbed cliffs. A few herbaceous plants are considered relict species, their geologic roots reaching back to an era when glaciers were a dominant part of the midwestern landscape.
Our state’s landscape is filled with rock-lined rivers such as the Gasconade, White, Meramec, Jacks Fork, Elk, Current and Eleven Point, along with their numerous smaller tributaries. As one navigates these scenic waters with paddle in hand, stone shelters and overhangs may come into view. These dry and moist sites, each with their own mix of stunted woody vegetation, vines, wildflowers and ferns, can be found by most observers.
Not all cliffs are composed the same. Like the variety of fishes found beneath the glistening Ozark waters, so too are the various exposures of Missouri’s rock legends.
Plants differ from one cliff community to the next as well. Often the collection of flora found growing on one type of rock are displayed either sparsely or not at all upon another due to unique microhabitats. While some plants grow upon several different rock face communities, other species are totally restricted to select regional locations within the state. A major determining factor of plant composition on cliffs is the acidity of the soil. Limestone and dolomite cliff soil tends to be basic or not acidic. Sandstone, igneous and chert cliff soil tends to be acidic.
Limestone and Dolomite
With their towering presence measuring 250 feet or more, limestone and dolomite