|Bladderpod, limestone glade, limestone glade bladderpod, Missouri bladderpod|
|Kimberlie McCue, Ph.D.|
The following Participating Institutions are custodians for this species in the CPC National Collection:
Missouri Botanical Garden
The conservation of Physaria filiformis is fully sponsored.
Kimberlie McCue, Ph.D. contributed to this Plant Profile.
Physaria filliformis is a winter annual. This means that it flowers and produces fruit in the early summer. Once hot weather arrives, plants disperse their seeds and die. These seeds lie dormant through the heat of the summer and germinate in the fall. They overwinter as a basal rosette, and then flower and fruit the following spring, beginning the cycle all over again.
In 1998, the U.S. Fish and Wildlife Service considered proposing this species for possible downlisting from Federally Endangered to Federally Threatened. According to the U.S. Fish and Wildlife Service, known sites of the species increased from 11 to 61 since the species was listed. This is in part due to increased surveying for the plant, but also due to increased habitat management that has restored the bladderpod in some areas.
Distribution & Occurrence
P. filiformis is restricted to limestone glades, sparsely vegetated grasslands with shallow soils and exposed bedrock. Low levels of disturbance help control the invasion of woody species. (USFWS 1988)
Commonly found with Arenaria petula, Camassia scilloides, Northoscordum bivalve, Opuntia humifusa, Satureja arkansana, Tradescantia tharpii, and Verbena canadensis. Bromus tectorum is a species of cheat grass which is invading the habitat of the Missouri Bladderpod. (USFWS 1988)
|Approximately 61 populations, primarily in southwest Missouri. The number of individuals can vary dramatically from year to year. As an example, one site at Wilson's Creek Battlefield has been monitored for ten years. The number of individuals observed has ranged from zero to over three hundred thousand from year to year. (USFWS 1988)|
Conservation, Ecology & Research
It is thought that seed dispersal occurs through wind and rainwater runoff.
Physaria filiformis often occurs in patches of sparse vegetation where disturbances from frost heaving and/or insect and rodent activity open up small pocket of bare soil.
Invasion of woody species and/or exotic species
Highway maintenance activities along rights-of-way, including mowing and herbiciding
Population ecology, including seed dormancy and seed bank studies, plant survivorship, and reproductive success studies (Thomas 1996)
The Missouri Department of Conservation has developed a list of "Best Management Practices" for landowners and managers (e.g. avoid non-specific herbicide use in areas of Missouri bladderpod between October and July).
Habitat restoration such as cedar clearing and burning has been done in some areas and has resulted in successful re-establishment of the Bladderpod (one such area is Rocky Barrens near Springfield, MO)
Determine how natural disturbances (such as fire) contribute to the long-term persistence of the species
Better understanding of population biology
Maintain habitat heterogeneity (Thomas 1996) to ensure long-term persistence of the species in an unpredictable environment
Rollins, R.C.; Shaw, E.A. 1973. The genus Lesquerella (Cruciferae) in North America. Cambridge, MA: Harvard University Press. 288p.