Chihuahuan scurfpea  Pediomelum pentaphyllum
ESA status: petitioned for listing

Chihuahuan Scurfpea photo

In the early 1900s, the Chihuahuan scurfpea made regular appearances at markets in Chihuahua City, Mexico, and was thought to be fairly common in the area. The Tarahumara people collected it for its medicinal properties – it helps reduce fever and may have other, unknown pharmaceutical benefits. But nowadays, this scurfpea is far and few between.

During rainy years, its short-stemmed, light colored foliage and small purple flowers emerge from the sandy loam soils of the Chihuahua Desert floristic region. But during dry years its thick, tuberous taproot enables it to weather the drought by remaining dormant, and it stays hidden beneath the soil. Because of this, it has always been a difficult plant to locate, but over the past 100 years, it has become even harder to find as populations have been extirpated from Chihuahua and Texas. Only around 300 known plants remain in two locations, one in New Mexico and one in Arizona, where it was only rediscovered in 2006.

Little is known about the scurfpea – its method of seed dispersal, its preferred associates among other plants, and much else about its ecology and biology remain a mystery. We don’t even know if the habitat it currently occupies is optimal, since the places where it has been located are highly disturbed. We do know that it is threatened by herbicides, habitat degradation, and livestock grazing, and that if it is not protected under the Endangered Species Act, we may never discover what other secrets this rare plant may hold.

Herbicides have been applied to Bureau of Land Management (BLM) lands the scurfpea occupies in New Mexico in order to reduce brush species for grazing permitees, with little consideration for this rare plant. In fact the potential loss of the entire scurfpea population in the herbicide treatment area was deemed an “acceptable risk” by the BLM. The areas where it currently grows have been heavily overgrazed, leaving little vegetation to anchor the soil. Wind erosion and flooding are rapidly undercutting the deep sandy soils the scurfpea needs. Grazing has also converted its former grassland home to shrub-dominated areas, leaving the scurfpea to struggle on in highly disturbed habitat.

WildEarth Guardians is urging the federal government to list the scurfpea under the ESA. We are working to ensure that the secrets held in the taproot of the Chihuahuan scurfpea don’t stay buried forever in dry ground.

photo credit: Mike Howard, Bureau of Land Management, 2006