State Status: Pennsylvania Endangered (PE)
PBS Status: Pennsylvania Endangered (PE)
Global Rank: G5
State Rank: S1
Did You Know?
Since this species closely resembles the seedlings of many other sedge species living in the same habitat experts can use the unique shape of the flower head to correctly identify the plant.
Common hemicarpa (Lipocarpha micrantha) is a tiny annual herb that may grow to 10cm in height, but often is less than 2.5cm. It has a tufted appearance with very narrow, hair-like leaves. The minute flowers, appearing from July to September, are grouped in compact clusters that are half a centimeter or less in length. Each cluster is subtended by hair-like bracts that well exceed the length of the cluster.
Critically imperiled in the nation or state because of extreme rarity (often 5 or fewer occurrences) or because of some factor(s) such as very steep declines making it especially vulnerable to extirpation from the state.
The PA Biological Survey (PABS) considers common hemicarpa to be a species of special concern, based on the few occurrences that have been recently confirmed and the specialized habitat. It has a PA legal rarity status and a PABS suggested rarity status of Endangered. Fewer than five populations are known from the state.
It grows on sandy shorelines along Lake Erie and in scoured river beds and shores of the Susquehanna River in the eastern part of the state.
Fruits July - October
In Pennsylvania, it has been documented historically only in a few widely scattered counties.
Invasive species may be a threat in some locations.
The viability of the known populations of common hemicarpa and its habitat will require maintaining the natural seasonal hydrologic fluctuations of the Susquehanna River and Lake Erie, as well as retaining the natural conditions of the shorelines and islands.
Conservation Status Map
NatureServe. 2017. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available https://explorer.natureserve.org.
- NatureServe. 2018. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available at https://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.