Harperella

Ptilimnium nodosum

Description

Harperella, Ptilimnium nodosum, is an annual herb with stems that range from 8-39 in (20-100 cm) in height. The distinctive leaf is a hollow, quill-like structure. Small white flowers, similar to those of Queen Anne's Lace, appear from May until the first frost.

Habitat

This plant is generally found on rocky or gravelly shoals of swift-flowing streams, along the edges of pineland ponds, in damp meadows, or in soggy ground around springs. Plants tolerate moderate flooding but can be smothered by silt deposits.

Distribution

Historically, harperella was found in a variety of wetland habitats in a range that extended from Maryland west into West Virginia, and south along the Atlantic Coastal Plain into Georgia and Alabama. Two of the earliest documented sites at Harpers Ferry, West Virginia, and Hancock, Maryland, were destroyed in the late 1800s by the construction of canals and railroads. One site in Alabama was flooded by a reservoir, and a second lost to excessive siltation. In 1984 a privately owned site in West Virginia that sustained a population of more than 10,000 plants was destroyed by construction of a housing subdivision.

The species has been extirpated from more than half of its historic range. Remaining harperella populations are found in discrete localities across seven Mid-Atlantic states: Alabama, Arkansas, Georgia, Maryland, North Carolina, South Carolina, and West Virginia. The largest populations are found along rivers and streams. The size and distribution of these populations can change drastically from year to year, depending on the amount of seasonal run-off and the amount of silt deposited at various sites. Pond bank populations are generally more stable than stream populations but are smaller, numbering in the hundreds of plants. The smallest populations are located in bogs or in the immediate vicinity of spring seeps.

A large Alabama population is found along a short stretch of the Little River in DeKalb County. Maryland populations occur along Sideling Hill Creek and Fifteen-Mile Creek in Allegany and Washington counties. In 1990, using funds from the Maryland Heritage Conservation Fund, the Maryland Department of Natural Resources, and The Nature Conservancy acquired more than 1,000 acres (400 hectares) along Sideling Hill Creek to protect the plant.

One large North Carolina population is found on a stretch of the Deep River in Chatham County; a smaller population occurs in Granville County on a Tar River tributary.

In West Virginia, populations exist in Morgan County along the Cacapon River and Sleepy Creek. In the summer of 1990 botanists from the West Virginia Natural Heritage Program surveyed the state's harperella populations. Of the two populations, one contained more than one million individuals and the second had more than 100,000.

In 1992, while conducting a 55-site survey of the Ouachita Mountain area in Oklahoma and Arkansas, the Arkansas Natural Heritage Commission discovered the harperella in two additional Arkansas counties, extending its range to Montgomery and Polk Counties from the locations known in 1990 in Scott and Yell Counties. In the Ouachita Mountains, researchers found harperella at 10 sites in five separate watercourses. Population sizes ranged from several hundred to more than 5,000 plants. All appeared to be stable, and no immediate or direct threats were identified. With the exception of one population in the Fouche LaFave River basin, all populations were found in the Ouachita River watershed. Most of the plants in this area are afforded a measure of protection by their location on the Ouachita National Forest.

Small, widely scattered populations in Georgia (Greene County) and South Carolina (Aiken and Saluda counties) are found beside ponds and in bogs and seeps. In the 1980s, botanists searched intensively for new harperella populations in these states, examining several hundred streams and ponds without success.

Threats

Extensive agricultural and industrial development throughout the mid-Atlantic region probably resulted in the elimination of up to 50% of the wet-lands that formerly sustained harperella populations. Numerous wetlands have been filled or drained. Construction of dams, reservoirs, and diversion structures has altered water flows and water tables, inundating some sites while drying up others. Farming and mining increased the amount of silt carried by streams, smothering plants with deposits. In recent years, residential development— notably home and road construction—has destroyed population sites or instituted changes in water drainage patterns that resulted in lowered water tables and a general drying of habitat.

Because of the plant's very specific habitat requirements, it can be easily extirpated from an area by even seemingly minor disturbances. In riverine situations, prolonged or intensified flooding as a result of upstream land use changes could wash away its substrate and its seed bank. On the other hand, reductions or lack of flooding, as from upstream impoundments, could decrease the species' competitive edge over more common streamside plants. In pond situations, irrigation and/or agriculture would be of obvious detriment to the species. Conversion to permanent ponds could also eliminate this species.

Conservation and Recovery

Continued loss or degradation of habitat is the primary threat to the survival of harperella. The few populations that occur on state-owned land or on nature preserves are relatively more secure. The Maryland Natural Heritage Program has strongly supported research into this plant's biology and habitat requirements and is currently experimenting with transplanting techniques that may allow the establishment of new populations. To preserve the population in that state, the Maryland Department of Natural Resources and The Nature Conservancy have acquired more than 1,000 acres (400 hectares) near Sideling Hill Creek to protect the species. This includes most of the remaining harperella individuals on private property within the state.

The species' reliance on streams and ponds is highly specific, and the U. S. Army Corps of Engineers has been more active in recent years in the protection of wetlands. Filling and draining wet-lands requires a permit from the Corps, which can be denied if these actions pose a threat to a federally listed plant.

Contacts

Regional Office of Endangered Species
U. S. Fish and Wildlife Service
1875 Century Blvd., Suite 200
Atlanta, Georgia 30345
http://southeast.fws.gov/

Regional Office of Endangered Species
U.S. Fish and Wildlife Service
300 Westgate Center Dr.
Hadley, Massachusetts 01035
http://northeast.fws.gov/

References

Kral, R. 1981. "Notes On Some Quill-Leaved Umbellifers." Sida 9:124-134.

Maddox, G. D., and R. Bartgis. 1989. "Ptilimnium nodosum (Harperella) in Maryland: A Progress Report on Conservation and Research Activities." Maryland Natural Heritage Program, Department of Natural Resources, Annapolis, Maryland.

U.S. Fish and Wildlife Service. 1990. "(Draft) Recovery Plan for Harperella." U.S. Fish and Wildlife Service, Newton Corner, Massachusetts.

U. S. Fish and Wildlife Service. 1990. "Report to Congress: Endangered and Threatened Species Recovery Program." U.S. Fish and Wildlife Service, Washington, D.C.