Opuntia macrorhiza is a common and widespread species of cactus with the common names plains prickly pear or twistspine pricklypear or Western pricklypear. It is found throughout the Great Plains of the United States, from Texas to Minnesota, as well as in the desert and Rocky Mountain states from Arizona to Idaho, with sporadic populations in the Mississippi and Ohio Valleys. It is also reported from northern Mexico, in the states of Chihuahua, Sonora, Coahuila, Nuevo León, Durango, Tamaulipas, and San Luís Potosí. The species is cultivated as an ornamental in other locations. The species prefers dry, sandy or gravelly soils. It is one of the shorter species of the genus, rarely over 30 cm (1 foot) tall, spreading horizontally and forming large clumps. Flowers are showy and bright yellow, sometimes with red markings near the base of the petals. Fruits are narrow, red, juicy and edible. Several varieties have proposed within the species. More study is needed to determine whether these should continue to be recognized as varieties, elevated to species status, or regarded as mere synonyms.
Hesperis matronalis is an herbaceous plant species in the mustard family, Brassicaceae. It has numerous common names, including dame's rocket, damask-violet, dame's-violet,dames-wort, dame's gilliflower, night-scented gilliflower, queen's gilliflower, rogue's gilliflower, summer lilac, sweet rocket, mother-of-the-evening, and winter gilliflower. These plants are biennials or short-lived perennials, native to Eurasia and cultivated in many other areas of the world for their attractive, spring-blooming flowers. In some of those areas, it has escaped from cultivation and become a weed species. The genus name Hesperis was probably given because the scent of the flowers becomes more conspicuous towards evening.