The mesquite in the Pilbara is a hybrid swarm of four different species, each with individual characteristics of overall plant shape, number of stems, leaf structure and size, mature pod colour and preference for attack by Evippe biological control. Within the population of mesquite in the Pilbara, we encounter plants right through the spectrum, from the typical Prosopis pallida shape of a single stem, tall tree-form plant with straw colour mature pods to the common multi-stemmed hybrid shrub with a range of mature pod colours including red and deep purple.