Western Prairie Fringed Orchid

Media
Photo of a western prairie fringed orchid plant with flowers
Status
Name
Endangered
Name
Threatened
Name
Species of Conservation Concern
Scientific Name
Platanthera praeclara
Family
Orchidaceae (orchids)
Description

Western prairie fringed orchid is a stout, erect plant 1–4 feet tall that can remain dormant in the soil during drought periods. It blooms mid-June through early July. The flowers are creamy to greenish white. Each flower has a hood-shaped petal with 3 deeply fringed lobes and a long nectar spur in back. The blossoms occur in showy clusters at the top of each plant. Leaves 2–5, elongated, keeled, along an angular stem.

Similar species: there are 8 species of fringed orchids in Missouri; here are the two most likely to be confused with western prairie fringed orchid:

  • Eastern prairie fringed orchid (P. leucophaea) is very similar to the western, and at one time they were considered a single species. Eastern prairie fringed orchid has rounded stems and smaller flowers than the western species. A federally threatened species, and a state endangered species, it was historically known from the eastern half of the state, but at this point it grows in only one location in our state.
  • Ragged orchis or ragged orchid (P. lacera) is smaller and has greener flowers, a narrower flower spike, and a shorter nectar spur. Of the 8 species of fringed orchids in Missouri, it is perhaps the commonest and therefore most likely to be confused with western prairie fringed orchid.
Size

Height: 10–33 inches.

Where To Find

In the past, found across the western part of the state. Now it is known to survive in only a few locations in northwest Missouri (Atchison, Harrison, and Holt counties).

Grows on moist sections of upland and bottomland prairies, often on calcareous substrates or on loess-derived soils.

This species, like the closely related eastern prairie fringed orchid, has been extirpated from much of its former range due to the plowing of native prairies and overgrazing. Both of Missouri’s prairie fringed orchids are federally listed as threatened. The biggest threat to the populations in northwest Missouri is the invasion of prairies by woody species and the possibility of prairies being plowed.

Federally threatened and state endangered. A Missouri species of conservation concern. It is illegal to remove these from the wild. Known from about five populations in the state.

Formerly considered the same as, or a variety of the eastern prairie fringed orchid. Although very similar, the two species have differences in flower color and the shape of the side (lateral) petals. Also, the two orchids have sufficiently different pollination characteristics that hybridization in nature is unlikely: Their floral structures are positioned slightly differently, so that the two orchids deposit pollen onto different parts of a visiting insect's body. This effectively prevents the two orchids from interbreeding.

Missouri’s orchids, even the relatively common ones, are not often seen, so the joy of discovering one in nature is a rare pleasure. Prairie fringed orchids are part of our state’s wild heritage, and they and their habitats need to be protected.

Because most of Missouri's orchids are rare, and many endangered or threatened, and because they almost always never survive transplanting, do not try to transplant them. Instead, enjoy them in their natural habitat.

As Missouri was settled, the plowing of native prairies destroyed uncountable populations of fringed orchids. A remarkable story of a surviving population was related by MDC's natural history biologist Steve Buback. "We learned of one stand of western prairie fringed orchids from a farmer who had never plowed a portion of his land because he made a bouquet of the orchids that bloomed there for his wife every year, which, oddly enough, led to long-term conservation."

Prairie fringed orchids are most fragrant at night to attract sphinx moths, their only pollinators. The sphinx moths, as caterpillars, rely on the presence of particular larval food plants. This is a reminder of how interconnected nature is, and how we must conserve not just individual plants or animals, but the entire prairie; the whole ecosystem.

One of the reasons why native tallgrass prairies are so valuable is their amazing diversity, and this species is a rare but unique component of prairie habitat.

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A very simple way of thinking about the green world is to divide the vascular plants into two groups: woody and nonwoody (or herbaceous). But this is an artificial division; many plant families include some species that are woody and some that are not. The diversity of nonwoody vascular plants is staggering! Think of all the ferns, grasses, sedges, lilies, peas, sunflowers, nightshades, milkweeds, mustards, mints, and mallows — weeds and wildflowers — and many more!