Cleome serrulata (syn. Peritoma serrulata), commonly known as Rocky Mountain beeplant/beeweed, stinking-clover, bee spider-flower, skunk weed, Navajo spinach, and guaco, is a species of annual plant in the genus Cleome. Many species of insects are attracted to it, especially bees, which helps in the pollination of nearby plants. It is native to southern Canada and the western and central United States. The plant has often been used for food, to make dyes for paint, and as a treatment in traditional medicine. Taxonomy In 1814, Frederick Traugott Pursh described this species in the first volume of Flora Americae Septentrionalis, based upon specimens collected by the Lewis and Clark Expedition near the Vermillion River in South Dakota. In the first volume of Prodromus Systematis Naturalis Regni Vegetabilis in 1824, Augustin Pyramus de Candolle moved this species to a genus which he named Peritoma (replacing the earlier illegitimate name Atalanta Nuttall), and calling the species Peritoma serrulatum. In 1901, Edward Lee Greene expanded Candolle's Peritoma, including this species as Peritoma serrulatum DC. and Peritoma lutem Raf. as well as two other species that he knew little about. At least Peritoma serrulata has been determined to be a synonym of Cleome serrulata. Description Cleome serrulata is an annual plant growing to tall, with spirally arranged leaves. The leaves are trifoliate, diminutive teeth, and with three slender leaflets each long. The flowers are reddish-purple, pink, or white, with four petals and six long stamens. The fruit is a capsule long containing several seeds. Flowering lasts an extended period because it begins at the bottom of the stalk and works its way up. The onset of flowering and seed pods comes at the same time. Cell wall elasticity is higher in specimens that live in drier climates. The pollen is about in length with three furrows which have one pore each. Moisture, temperature, and time are critical in seed germination. Germination occurs during summer and plants can quickly grow to . Flowers are often covered with a variety of insects, especially bees. Elongated capsules contain the seeds, which are dark brown to black, curved, and have a wart-like appearance. After the seeds are dispersed, the plants begin decomposing. The plant is called waa’ in the Navajo language, tumi in the Hopi language, and both a'pilalu and ado:we in the Zuni language. Distribution and habitat Cleome serrulata is native in southern Canada from British Columbia to Ontario