Prosopis juliflora is a shrub or small tree in the family Fabaceae, a kind of mesquite. It is native to Mexico, South America and the Caribbean. It has become established as an invasive weed in Africa, Asia, Australia and elsewhere. It is a contributing factor to continuing transmission of malaria, especially during dry periods when sugar sources from native plants are largely unavailable to mosquitoes.

Mesquite is a common name for several plants in the genus Prosopis, which contains over 40 species of small leguminous trees. They are native to dry areas in the Americas. They have extremely long roots to seek water from very far under ground. As a legume, mesquites are one of the few sources of fixed nitrogen in the desert habitat. The trees bloom from spring to summer. They often produce fruits known as "pods". Prosopis spp. are able to grow up to 8 metres (26 ft) tall, depending on site and climate. They are deciduous and depending on location and rainfall have either deep or shallow roots. Prosopis is considered long-lived because of the low mortality rate after the dicotyledonous stage and juveniles are also able to survive in conditions with low light and drought. The Cahuilla indigenous people of western North America were known to eat the seeds of mesquite.