with other senegalias. A tentative connection has been made between these glands and insects that would suggest a mutualistic relationship (as found in other Senegalia species). Ants are known to use the glands as a source of food and water, and may provide some defense for the plant against herbivorous insects. Like other arroyo trees in family Fabaceae, S. greggii is frequently afflicted with Desert Mistletoe, Phoradendron californicum. Unlike other legumes, S. greggii is not known to form root nodule associations with nitrogen-fixing bacteria. It is argued that this species may be an example of an evolutionary anachronism, in which the range and renewal of the species is limited due to the extinction of the mammalian megafauna responsible for seed dispersal. Within this model, the scarification required to germinate the seeds would have occurred during the chewing and digestion of the fruit by a large mammal, who later passes the seed intact some distance from the original tree. Gambel quail eat the seeds. Antelope browse the foliage, but more delicate species may do so cautiously on account of the thorns. Ethnobotany Senegalia greggii, even though it is used as forage for livestock, contains a potentially poisonous cyanogenic glycoside called prunasin. Mature seeds are to be avoided, as the native people did. The young, unripe beans of S. greggii were gathered and eaten by desert tribes of North America, including the Chemehuevi of the Southern Paiute, the Pima, and the Cahuilla. The Cahuilla also ground the dried beans for mush and cakes, while the Havasupai ground it to make flour for bread. The Seri ground the beans to meal then mixed it with water and sea lion oil for porridge. The Diegueno used S. greggii as food for domesticated animals. The Pimas and Tohono O'odham ate the seeds as pinole. The Cahuilla and Pima used the fibers for sturdy construction material and firewood. The Havasupai split the twigs and used them for basketry, but also used the twigs as a broom to brush off metates. The O'odham used the broken twigs for baskets, and were curved to make intricate weaves in the baskets. The Pima used the dried bushes to pile them to make a brush fence. The branches were used to make cradle frames as well. The Tohono O'odham fitted the branches around deer hunters' heads to make a disguise, and the buds and blossoms were dried to make perfume