Nicotiana glauca is a South American species, naturalized in five states; it is most abundant in southwestern California, and the upper regions of the Sonoran Desert in Arizona. Plants are small trees, sometimes 20 feet high, but usually in the range six to ten feet. Branches are woody, the bark brownish, while leaves are glaucous, hairless, and relatively large, up to 8 inches.
The inflorescence, a small cluster, is subtended by short, linear bracts. Flowers have a hairless, light green calyx, around 0.4 inches long, divided into four unequal lobes (all shorter than the calyx tube), and a narrow, tubular, yellow corolla of up to 1.4 inches, finely pubescent on the outside. The five stamens are all equal in size, and attached towards the base of the tube.