Physaria obcordata

Dudley Bluffs Twinpod

FWS Focus


Dudley Bluffs twinpod is a herbaceous (non-woody) plant species in the mustard family (Brassicaceae). It is a compact plant with many raised branches arising from a deep tap root. The plant grows on average 4 to 7 inches tall and 7 inches wide. Stems are smooth and narrow with oval to arrowhead shaped leaves that are very dense at the base. Dudley Bluffs twinpod’s clusters of bright-yellow flowers bloom for a short time between mid-May and June. Dudley Bluffs twinpod is a close relative of the common sharpleaf twinpod (Physaria acutifolia) and it can be difficult to distinguish the two species at a glance. Dudley Bluffs twinpod is only known to occur in the general area of Piceance Creek in Rio Blanco County in western Colorado, near the town of Meeker. The species is restricted to barren (sparsely vegetated), white outcrops and steep slopes of the Parachute Creek Member and certain tongues of the Green River Formation. Its habitat is unique because it supports the growth of only a few plants that can tolerate difficult growing conditions. Why does the Dudley Bluffs twinpod need protection? The unique geology of the Piceance Creek area is important to the Dudley Bluffs twinpod (and many other endemic plant species). It is also part of the Piceance Basin’s multimineral oil shale zone, an area containing large reserves of oil shale, natural gas, and minerals. However, energy exploration, extraction, and the many associated activities in the region can disturb or degrade the fragile shale habitats. They can also pose a threat to native ground nesting bees that pollinate Dudley Bluffs twinpod. Other threats include weed invasion and increased access to these remote areas by recreationists.

Scientific Name

Physaria obcordata
Common Name
Dudley Bluffs twinpod
FWS Category
Flowering Plants

Location in Taxonomic Tree

Identification Numbers



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