Prosopis

Prosopis is a genus of flowering plants in the family Fabaceae. It contains around 45 species of spiny trees and shrubs found in subtropical and tropical regions of the Americas, Africa, Western Asia, and South Asia. They often thrive in arid soil and are resistant to drought, on occasion developing extremely deep root systems. Their wood is usually hard, dense and durable. Their fruits are pods and may contain large amounts of sugar. The generic name means "burdock" in late Latin and originated in the Greek language.

Selected species

 * Mesquites (southern United States, Mexico)
 * Prosopis glandulosa Torr. – honey mesquite; Haas (Cmiique Iitom)
 * Prosopis laevigata (Humb. & Bonpl. ex Willd.) M.C.Johnst. – smooth mesquite
 * Prosopis pubescens Benth. – screwbean mesquite
 * Prosopis reptans Benth. – tornillo
 * Prosopis velutina Wooton – velvet mesquite
 * "Algarrobos", bayahondas etc. (Neotropics, particularly the Gran Chaco)
 * Prosopis abbreviata Benth. – algarrobillo espinoso
 * Prosopis affinis Spreng. – nandubay, algarrobillo, espinillo, Ibopé-morotí
 * Prosopis alba Griseb. – algarrobo blanco; ibopé or igopé (Guaraní)
 * Prosopis caldenia Burkart – caldén
 * Prosopis chilensis (Molina) Stuntz – algarrobo Chileno, algarrobo blanco
 * Prosopis fiebrigii Harms
 * Prosopis flexuosa DC. – alpataco, algarrobo negro
 * Prosopis hassleri Harms
 * Prosopis juliflora (Sw.) DC. – bayahonda blanca, bayarone Français; kabuli kikar, vilayati babul, vilayati khejra or vilayati kikar (Hindi); trupillo or turpío (Wayuunaiki)
 * Prosopis kuntzei Harms ex Kuntze – itín, barba de tigre, carandá, palo mataco
 * Prosopis nigra (Griseb.) Hieron. – algarrobo negro, algarrobo amarillo, algarrobo dulce, algarrobo morado
 * Prosopis pallida (Humb. & Bonpl. ex Willd.) Kunth – American carob, huarango, kiawe (Hawaiian)
 * Prosopis rojasiana Burkart
 * Prosopis ruscifolia Griseb. – vinal
 * Prosopis strombulifera (Lam.) Benth. – creeping mesquite, Argentine screwbean
 * Prosopis tamarugo Phil. – tamarugo
 * African species
 * Asian species (India, mainly Rajasthan, Sri Lanka to the Arabian Peninsula)
 * Prosopis cineraria ** Prosopis spicigera (L.) Druce – jand; ghaf (Arabic); sami or sumri (Gujarati); khejri, sangri (Rajasthani); kandi'' (Sindhi)
 * Prosopis farcta (Sol. ex Russell) J.F.Macbr.
 * Prosopis koelziana Burkart (Iran)

Formerly placed here

 * Anonychium africanum (Guill. & Perr.) C.E.Hughes & G.P.Lewis (as P. africana)– gele (Malinke, traditional djembe wood)
 * Acacia atramentaria Benth. (as P. astringens Gillies ex Hook. & Arn. )
 * Elephantorrhiza elephantina (Burch.) Skeels (as P. elephantina (Burch.) E.Mey. or P. elephantorrhiza Spreng. )
 * Prosopidastrum globosum (Gillies ex Hook. & Arn.) Burkart (as P. globosa Gillies ex Hook. & Arn. )

Taxonomic reclassification
Genomic research published in 2022 concludes that species grouped under the genus Prosopis actually represent multiple genera including Anonychium, Neltuma, Prosopis, and Strombocarpa.

Phytochemistry
Prosopis species have been found to contain 5-hydroxytryptamine, apigenin, isorhamnetin-3-diglucoside, l-arabinose, quercetin, tannin, and tryptamine.

The tannins present in Prosopis species are of the pyrogallotannin and pyrocatecollic types. The tannins are mainly found in the bark and wood, while their concentration in the pods is low.

Some species, such as P. africana or P. velutina, produce a gum (mesquite gum).

As an introduced and invasive species
The species Prosopis pallida was introduced to Hawaii in 1828 and now dominates many of the drier coastal parts of the islands, where it is called the kiawe tree and is a prime source of monofloral honey production.

In Australia, invasive Prosopis species are causing severe economic and environmental damage. With their thorns and many low branches, Prosopis shrubs form impenetrable thickets which prevent cattle from accessing watering holes, etc. They also take over pastoral grasslands and suck up scarce water. Prosopis species cause land erosion due to loss of grassland that are habitats for native plants and animals. Prosopis thickets also provide shelter for feral animals such as pigs and cats.

For more information on invasiveness of mesquite species, see Prosopis glandulosa and Prosopis juliflora.

Eradication
Eradicating Prosopis is difficult because the plant's bud regeneration zone can extend down to 6 in below ground level; the tree can regenerate from a piece of root left in the soil. Some herbicides are not effective or only partially effective against mesquite. Spray techniques for removal, while effective against short-term regrowth, are expensive, costing more than $70/acre ($170/hectare) in the USA. Removing large trees requires tracked equipment; costs can approach $2,000 per acre. In Australia, several techniques are used to remove Prosopis.

General references

 * Paciecznik, N. M., Harris P. J. C., & S. J. Smith. 2003. Identifying Tropical Prosopis Species: A Field Guide. HDRA, Coventry, UK. ISBN 0-905343-34-4.
 * Handbook on taxonomy of Prosopis in Mexico, Peru and Chile (FAO Document Repository)
 * Plant Walk I: Old Main (website of the Vascular Plant Herbarium of the University of Arizona in Tucson)
 * Plant Walk 1 UofA
 * Plant Walk 2 UofA