Physaria filiformis

Limestoneglade Bladderpod

FWS Focus

Overview

Characteristics
Overview

Missouri bladderpods grow mostly in open limestone glades, but have also been found on one dolomite glade in Arkansas. Glades are naturally dry, treeless areas with shallow, loose soil and areas of exposed rock. Glades are described by the underlying rock, for example limestone or dolomite. Sometimes the bladderpod is found on highway rights-of-way and pastures where mowing and grazing have kept the area open. Occasionally it is found in open rocky woods. 

Threats to Missouri bladderpod include habitat loss to the natural glade habitat of the Missouri bladderpod is threatened with residential development, overgrazing and competition from encroaching woody and non-native grasses. Lack of fire on the landscape is also negatively impacting the species. Historically, natural disturbances such as fire kept the glades open and free of trees and shrubs. With aggressive control and prevention of wild fires, woody plants and introduced grasses have invaded glades. The Missouri bladderpod can only grow in open areas; it cannot compete with these plants. Thus, it dies out when glades are overgrown with species such as red cedar, cheat grass and fescue. 

Roadside maintenance also has a potential negative impact on Missouri bladderpod, with some populations that are found on roadsides being threatened by herbicides or mowing.

The Missouri bladderpod was added to the federal list of endangered and threatened plants on January 8, 1987 as an endangered species. As a result of this listing, the U.S. Fish and Wildlife Service prepared a recovery plan that identified priority conservation actions. Those actions include protecting and monitoring existing populations, surveying for new populations, habitat protection and public education. Progress made toward recovery prompted the U.S. Fish and Wildlife Service to reclassify the bladderpod from endangered to threatened in October 2003.

Research has focused on environmental conditions that affect germination and survival. This knowledge was used to develop appropriate management for the species, including prescribed burns every three to five years in August. These burns remove organic debris and set back woody vegetation. They apparently do not harm Missouri bladderpods because the seeds have not yet germinated. 

Habitat Protection and Management 

Several Missouri bladderpod populations are on public land that is now managed to protect this species. Additional sites have been purchased by conservation organizations and government agencies to ensure that they remain protected and properly managed. Also, the Missouri Department of Conservation and The Nature Conservancy have worked with private landowners to share the habitat needs of the Missouri bladderpod and to provide landowners with suggestions on glade management.

Scientific Name

Physaria filiformis
Common Name
limestoneglade bladderpod
Missouri bladderpod
FWS Category
Flowering Plants
Kingdom

Location in Taxonomic Tree

Identification Numbers

TSN:

Characteristics

Characteristic category

Life Cycle

Characteristics
Life Cycle

Seeds of the Missouri bladderpod germinate in the fall, then overwinter as basal rosettes, a cluster of leaves on the ground. The plant blooms in spring from April through May and dies by late June. Seeds produced during spring survive the hot summer by lying dormant. They then germinate in the fall, starting the cycle over again. However, this life cycle varies from year to year depending on weather and soil conditions. Under ideal conditions, bladderpods are numerous and broadly distributed across available habitat, and individual plants have more stems and more flowers. In contrast, under unfavorable conditions, there may be few to no plants at a site for one to several years. However, some seeds that didn’t germinate will remain viable and will grow in a year or later when conditions are favorable 

Characteristic category

Food

Characteristics
Food
Characteristic category

Similar Species

Characteristics
Similar Species

One other Physaria species, spreading bladderpod (Physaria gracilis), occurs in Missouri. Unlike Missouri bladderpod, spreading bladderpod does not have a silvery-gray appearance, and it does not occur within the range of Missouri bladderpod. 

Characteristic category

Habitat

Characteristics
Habitat

Missouri bladderpods grow mostly in open limestone glades, but have also been found on one dolomite glade in Arkansas. Glades are naturally dry, treeless areas with shallow, loose soil and areas of exposed rock. Glades are described by the underlying rock, for example limestone or dolomite. Sometimes the bladderpod is found on highway rights-of-way and pastures where mowing and grazing have kept the area open. Occasionally it is found in open rocky woods.

Geography

Characteristics
Range

The Missouri bladderpod is restricted to southern Missouri and northern Arkansas. It was probably never found beyond this range but was known from only nine sites in three counties when it was first listed as endangered in 1987. After additional surveys were conducted and actions undertaken to conserve the bladderpod, the number of documented populations increased to 61 sites in four counties in Missouri and two sites in two counties in Arkansas. 

Launch Interactive Map

Timeline

Explore the information available for this taxon's timeline. You can select an event on the timeline to view more information, or cycle through the content available in the carousel below.

7 Items