Ashy dogweed

This plant, a shrub or subshrub, produces a clump of stems up to 30 centimeters tall. The herbage is ashy gray-green, gray, or whitish due to a layer of white woolly hairs. The leaves are linear to threadlike and are arranged alternately along the stems. They measure 1 to 1.5 centimeters long. The inflorescence is a flower head with a bell-shaped involucre of woolly-haired phyllaries. There are 12 or 13 yellow ray florets and about 30 disc florets at the center. The fruit is an achene with a pappus of scales. Blooming occurs mostly in March through May but it may bloom at other times depending on rainfall.

Thymophylla tephroleuca prefers fine sand or sandy-loam soils. Its current habitat is predominately shrub-invaded grasslands. This plant is likely a relict, a rare species remaining in a grassland habitat type that was once more common. Most of the local territory has converted to brushland dominated by cenizo (Leucophyllum frutescens) blackbrush (Coleogyne ramosissima), and creosote bush (Larrea tridentata). Other dominant plant species include mesquite (Prosopis glandulosa), goatbush (Castela texana), anacahuita (Cordia boissieri), and javelina brush (Microrhamnus ericoides). The introduced buffelgrass (Cenchrus ciliaris) is common.