Clammy Weed
Polanisia dodecandra trachysperma
Photo taken at Mesquite Wash, e. Maricopa Co., Arizona, USA on Sept. 24 by K. Darrow.
Along sandy washes after the summer rains have kicked in these annuals germinate quickly and soon begin producing whitish flowers and mustard-like pods. Conspicuously, the dozen or so stamens have purple filaments. The trifoliate leaves and developing pods have copious stickiness and emit a very pungent odor when crushed or brushed against. Exceptional plants may be over a meter tall.
Clammy weed is found along sandy, but well-watered washes above 800 m in the Sonoran Desert in Arizona and Sonora.