Prosopis pallida: Information from Answers.com

Prosopis pallida

Scientific classification
Kingdom:	Plantae
Division:	Magnoliophyta
Class:	Magnoliopsida
Order:	Fabales
Family:	Fabaceae
Subfamily:	Mimosoideae
Tribe:	Mimoseae
Genus:	Prosopis
Species:	P. pallida
Binomial name
*Prosopis pallida* (Humb. & Bonpl. ex Willd.) Kunth

Prosopis pallida (syn. Prosopis limensis) is a species of mesquite tree. It has the common names kiawe, huarango, and American carob, as well as "bayahonda" (a generic term for Prosopis) and "algarrobo blanco" (usually used for Prosopis alba). It is a thorny legume, native to Colombia, Ecuador and Peru, particularly drier areas near the coast. While threatened in its native habitat, it is considered an invasive species in many other places.

The kiawe is a spreading bush or moderately-sized tree bearing spines, spikes of greenish-yellow flowers, and long pods filled with small brown seeds. It is a successful invasive plant due to its ability to reproduce in two ways: production of large numbers of easily-dispersed seeds, and suckering to create thick monotypic stands that shade out all competing plants nearby. It survives well in dry environments due to an extremely long taproot. It is so efficient at withdrawing moisture from soil that it can kill nearby plants by depriving them of water. It can be found in areas where other plants do not grow, such as sandy, dry, degraded slopes, salty soils, disturbed areas, and rocky cliffs.

The tree grows quickly and can live for over a millennium. It makes a good shade tree, and its hard wood is a source of long-burning firewood and charcoal.^[1] At times it has been used to replace forest and prevent erosion, and once it was established it generally dominated the habitat. Kiawe pods can be used as livestock fodder, ground into flour, sweetened into molasses or turned into beer.^[1] The light yellow flowers are attractive to bees.

The tree was introduced to Puerto Rico and Hawaii as well as New South Wales and Queensland in Australia and it is now considered to be naturalised in those places. The first kiawe was planted in Hawaii in 1828; today it is a ubiquitous shade tree and invasive weed on the Hawaiian Islands, but provides firewood for heating and grilling.

The clearing of kiawe (huarango) has been suggested as a major reason for the collapse of the Nazca society in southern Peru circa AD 500 after an El Nino event led to flooding, erosion and desertification.^[2]

Ecologist consider the huarango an important element of the ecosystem of the desert area west of the Andes in southern Peru, because of its ability to bind moisture and counter erosion. Despite prohibitions by regional authorities, poor local villagers keep cutting down the trees for charcoal. Efforts are under way to reforest the area with huarangos.^[1]^[3]