Wireweed

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Wireweed

Polygonella basiramia

Status	Endangered
Listed	January 21, 1987
Family	Polygonaceae (Buckwheat)
Description	Annual herb with a cluster of stems and hairlike leaves.
Habitat	Lake Wales Ridge; sand pine scrub.
Threats	Agricultural and residential development, fire suppression.
Range	Florida

Description

Wireweed, Polygonella basiramia, is an annual plant with as many as 30 erect, slender branches of nearly equal height. The stems grow from a taproot to reach a height of about 2.5 ft (80 cm) and bear numerous hairlike leaves no more than 0.8 in (2 cm) long. In the fall, wireweed produces clusters of white flowers on the branch tips. The plant is conspicuous only when in bloom.

Wireweed is closely related to Polygonella ciliata, a species that ranges from Orlando southward, and has even been classified as a variety of it: Polygonella ciliata var. basiramia.

Habitat

Wireweed grows in association with the sand pine and rosemary scrub of Florida's southern Lake Wales Ridge. It prefers open, barren spaces in full sunlight and will not tolerate shade. Wireweed thrives where patches of scrub vegetation alternate with patches of bare sand. The plant is highly adapted to fire and benefits from periodic brushfires. Many other endemic plants from the Lake Wales Ridge are rare and endangered, such as the federally listed Highlands scrub hypericum (Hypeicum cumulicola ).

Distribution

In 1920, wireweed was collected east of Lake Josephine in Highlands County. It is native to Polk and Highlands counties, Florida. The geographic range extends from Crooked Lake and Lake Weohyakapka to the southern end of the Lake Wales Ridge near Archbold Biological Station.

Today, wireweed plants grow in small numbers scattered throughout Highlands, Polk, and Osceola counties. Some of the known sites lie within the Highlands Hammock State Park and Archbold Biological Station. It was estimated by 1989, that fewer than 100 plants survived.

Threats

Much of the sand pine scrub habitat of south-central Florida has been lost, first to agricultural development (especially citrus groves), and more recently to housing subdivisions. Remaining scrub is threatened by fire suppression. When scrub does not burn periodically, other plants crowd out wire-weed and its associates. Wireweed is particularly vulnerable because it is one of the first plants to revegetate a burned-over, barren area. Archbold Biological Station conducts controlled burns within the preserve, which should improve the vigor of plants there.

Conservation and Recovery

The U.S. Fish and Wildlife Service (FWS) is planning a Scrub Refuge in Highlands County to encompass various disparate parcels of scrub and provide habitat protection on a regional scale. Together with proposed state acquisitions in Highlands and Polk counties, such a refuge would stem loss of habitat and provide permanent protection for dozens of rare endemic plants, including the wire-weed.

Recovery efforts for this species are outlined in the Recovery Plan for Nineteen Florida Scrub and High Pineland Plants, first announced in draft form by the FWS in 1995. The recovery plan outlines basic elements necessary to restore the wireweed and other endangered plants. These include habitat protection through land purchase and other means (including the Habitat Conservation Plan process for threatened animals in the Florida scrub habitat); the management of protected habitats; and the assessment of progress and plan post-recovery monitoring.

This plan is a revision and expansion of a recovery plan, published in 1990, that covered eleven of these plant species. The 1990 edition emphasized the need for land acquisition to protect these plants. At the time, the State and private organizations had already made significant acquisitions, and more have been accomplished since then (including initial land purchase for the Lake Wales Ridge National Wildlife Refuge). These land purchases, accompanied by other elements of the recovery plan, are likely to assure full recovery, or at least down-listing, of the large majority of the nineteen plants, especially wireweed. The recovery potential is excellent, provided preservation of habitat is accomplished in a timely manner since the species seems to thrive so long as its habitat is preserved.