Description
Herbaceous biennial that grows to approximately 60 cm tall.  Branches arise from near the base of the stem. The leaves closest to the ground are approximately 5 cm long with wavy edges and are arranged in a rosette. Stem leaves are shorter, narrow, and have smooth edges. Flowers appear in loose spikes at the ends of the stems. Flowers have four purple petals approximately 2 cm in length, each of which is borne on a short (0.6 cm) stalk. Fruits are long, slender pods. Moist, alkaline meadow habitats are favored at an approximate elevation of 1,000 to 1,100 meters in northeast Oregon.  T. howellii ssp. spectabilis can be told apart from T. howellii ssp. howellii by the later having larger petals and un-united paired filaments.  Their ranges in eastern Oregon do not overlap.

Threats: habitat destruction and fragmentation from agricultural and urban development, grazing by domestic livestock, competition from non-native vegetation, and alterations of wetland hydrology

Overview
Up until 1980, Thelypodium howellii ssp. spectabilis was thought to be extinct.  Now there are 11 sites known in Oregon’s Baker and Union counties, all on private lands within a 13-mile radius of Haines.  This species occupies a total habitat of only approximately 40 ha (100 ac), 6 sites are 0.4 hectares or less, making them especially vulnerable.  Only one population, of almost 17 hectares, is on land that is being managed through land easement for the protection of this species. All other populations are vulnerable to threats from development, recreation, agriculture, and invasion of exotic plants.  Grazing, which is presently a substantial threat, can be managed to minmize impact if it occurs after seed dispersal.  Herbicide use is a potential serious threat since all known populations have been invaded by noxious weeds (teasel and thistles).  Those sites that have been monitored since the 1980’s seem to be in decline.  Of those sites sampled in North Powder since 1990, at least 40% have been extirpated.  The third largest population that is located in Haines dropped from over 5,000 to less than 300 plants after a rodeo in 1994 extended its parking lot.  It appears to re-colonize well after flooding, a process which is often prevented by flood control and irrigation.  Current protection strategies include working with landowners, who have been notified of the plant presence on their land, to determine safe grazing and weed control methods, as well as population surveys, marking roadside populations to prevent damage during maintenance, and incentive programs offering funding to landowners.
 

Distribution   Though once thought extinct, there are now 11 know sites in Oregon's Baker and Union Counties.

North American Distribution (map from the Biota of North America Program)

Distribution by County

Sources
U.S. Fish and Wildlife Service, 1999 Federal Register, 28393, Howell's spectacular thelypody.
 
 

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