About Prosopis strombulifera (Lam.) Benth.
Strombocarpa strombulifera, formerly classified as Prosopis strombulifera, is a species of mesquite (also called algarrobo) that grows as a shrub in the legume family. Its English common names are Argentine screwbean and creeping screwbean, and its Spanish common name is retortuño. This shrub is native to Argentina, where it grows in arid and saline soils. After being introduced to Imperial County, California, it became established in the wild and is known there as an invasive noxious weed. This plant grows from a network of long, spreading roots, and may reach up to three meters in height. Multiple plants often grow together in an area, forming a monotypic stand. The shrub has waxy-textured leaves formed from a pair of leaflets; each of these primary leaflets is further divided into several pairs of secondary leaflets, each up to one centimeter long. Whitish spines up to 2 cm long grow near the leaf bases. The inflorescence is a spherical head made up of many very narrow, tube-shaped yellow flowers, and the entire head measures approximately 1.5 cm wide. The fruit is a bright yellow seed pod that coils tightly into a cylindrical stick up to 5 cm long. It contains several greenish seeds, each about 0.5 cm long.
