Encyclopedia of the Great Plains

WILDFLOWERS

The term "wildflowers" usually refers to attractive native flowering species. In the Great Plains the category often includes plants that are native elsewhere but have naturalized (reproducing on their own) in the Great Plains region. It rarely includes grasses, because grass flowers are small, but some grass flowers are very colorful and the foliage is often striking. Flowering shrubs and trees are not usually considered wildflowers, but there are a number of handsome natives such as wild plums (Prunus) and redbuds (Cercis).

The native wildflowers of the grasslands are likely declining in numbers because their natural habitats–native grasslands, forests, and wetlands–have been replaced by fields as well as urban and suburban areas. Some, such as Liatris (gay feather) and Coreopsis, have been successfully brought into cultivation. Some species, such as purple coneflowers (Echinacea), are being collected for their medicinal properties to the point that they are increasingly difficult to find in their natural environment. Other species are decreasing because they depend on parts of the ecosystem that are no longer present, as is in the case of Ruellia humilis (Acanthaceae), which was once apparently pollinated by a moth that has become extinct in some areas.

The Great Plains is especially rich in showy flowers of the plant families Asteraceae (sunflowers, asters, coneflowers), Fabaceae (peas, clovers), Onagraceae (evening primroses), and Asclepiadaceae (milkweeds). Native wildflowers are mostly yellow, blue, or purple in color, with true reds being rare. White flowers, especially those with long tubes (corollas), usually open at night and some have wonderful fragrances. Colors reflect the preferences of pollinators: bees, flies, and butterflies prefer bright colors and visit plants by day, while moths and hawkmoths fly by night. Partly white flowers (e.g., Gaura) may be visited by both kinds of pollinators.

The flowering of prairie plants can be divided into five seasons: early spring, late spring, early summer, late summer, and fall. Examples of flowers reflecting that seasonal sequence include pasque flower (Anemone patens) early in the spring; puccoon (various Lithospermum species) in late spring; scurf peas (Psoralea) in June; milkweeds (Asclepias species) in late summer; and asters and gentians in fall.

A few native wildflowers are found across the entire region, but more often, similar species occur in sequence along east–west and north– south transects. These plants are adapted to the area where they are found, and this local diversity increases the variety of native species. Likewise, in many cases there are distinctive species or varieties confined to special growing conditions, such as sand, rocky outcrops, and wetlands. Milkweeds are a good example. The common milkweed (Asclepias syriaca) is found in the Eastern Plains. It is replaced in the Western Plains by the similar showy milkweed (A. speciosa). The swamp milkweed (A. incarnata), with leaves much narrower and the flowers a more reddish pink than the previous two, is found in marshy areas and wet meadows across the region. And on sand the characteristic milkweed is the green-flowered sand milkweed (A. arenaria).

Plants of human-disturbed environments (highway margins, lawns) are usually called weeds. Whether native or introduced, these occur across the entire Great Plains. Many familiar roadside wildflowers, such as goatsbeard (Tragopogon), sweet clover (Melilotus), and dame's rocket (Hesperis), were introduced.

Within our region, forested areas harbor a distinct group of wildflowers. In most cases these are species shared with more extensive forests in the east or southeast, such as spring beauty (Claytonia virginica), mayapple (Podophyllum peltatum), and touch-me-not (Impatiens species).

Since flowers are necessary for plant reproduction, picking bouquets of wildflowers poses a threat to their survival, especially for the nonweedy species. As the human impact in the Great Plains increases and more areas are developed, threats to native wildflowers will only get worse. Digging up native plants as a method of collecting them frequently fails because prairie natives are very deeply rooted and difficult to dig up. This is, therefore, an even greater threat to the survival of prairie species than picking the flowers.

Kathleen H. Keeler University of Nebraska-Lincoln

Freeman, C. C., and E. K. Schofield. Roadside Wildflowers of the Southern Great Plains. Lawrence: University Press of Kansas, 1991.

Great Plains Flora Association. Flora of the Great Plains. Lawrence: University Press of Kansas, 1987.

Weaver, J. E. Native Vegetation of Nebraska. Lincoln: University of Nebraska Press, 1965.