State Status: Pennsylvania Threatened (PT)
PBS Status: Pennsylvania Threatened (PT)
Global Rank: G5
State Rank: S2
Few-flowered nutrush (Scleria pauciflora) is a perennial herb with triangular, tufted stems that grow from 20-50cm. The leaves are alternately arranged, linear, elongate, variably hairy, and up to 3mm wide. The flowers, appearing from June to September, are minute, unisexual, and are grouped in clustered spikelets at the top of the stem. The fruits are less than 1.5-2mm long, but have a curious appearance in being hard and white (similar to a piece of bone or tooth), globe-shaped with a short-pointed tip, warty on the surface, and having a basal “platform” of six tuberlike structures.
Imperiled in the nation or state because of rarity due to very restricted range, very few populations (often 20 or fewer), steep declines, or other factors making it very vulnerable to extirpation from the nation or state.
The PA Biological Survey (PABS) considers few-flowered nutrush to be a species of special concern, based on the relatively few occurrences that have been recently confirmed and its specialized serpentine habitat. It has a PA legal rarity status and a PABS suggested rarity status of Threatened. About fifteen populations are currently known from the state.
It grows on serpentine barrens.
Fruits June - September
In Pennsylvania, it has been documented historically mostly in the southeastern counties
Quarrying and habitat loss are threats in some locations.
The viability of populations of few-flowered nutrush and its serpentine habitat will require maintaining early successional conditions and controlling invasive species. Active management, through the use of fire, scraping the substrate, or mowing, may be needed to create the proper successional stage and ecological conditions for this species to thrive.
Conservation Status Map
NatureServe. 2017. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available http://explorer.natureserve.org.
- NatureServe. 2018. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available at http://www.natureserve.org/explorer
- Pennsylvania Natural Heritage Program. 2018.
- Rhoads, A.F. and W.M. Klein, Jr. 1993. The Vascular Flora of Pennsylvania. American Philosophical Society, Philadelphia, Pennsylvania. Rhoads, A.F. and T.A. Block.
- 2007. The Plants of Pennsylvania: An Illustrated Manual. 2nd edition. University of Pennsylvania Press, Philadelphia, Pennsylvania.