Prosopis pallida

Species of legume

Prosopis pallida is a species of mesquite tree. It has the common names kiawe (/k//iː/'/ɑː//v//eɪ/) (in Hawaii), huarango (in its native South America) and American carob, as well as "bayahonda" (a generic term for Prosopis), "algarrobo pálido" (in some parts of Ecuador and Peru), and "algarrobo blanco" (usually used for Prosopis alba). It is a thorny legume, native to Colombia, Ecuador and Peru,

Fallen Kiawe branches usually contain sharp spines that can puncture both feet and tires.

At times the tree was used to replace forest and prevent erosion, and once it was established it generally dominates the habitat. It was introduced to Puerto Rico and Hawaii as well as New South Wales and Queensland in Australia and is now naturalized in those places. The first kiawe was planted in Hawaii in 1828;

The clearing of kiawe (huarango) has been suggested as a major reason for the collapse of the Nazca culture in southern Peru at the beginning of the 6th century AD after an El Niño event led to flooding, erosion and desertification.

Ecologists consider the huarango important to 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 villagers continue to harvest the trees to make charcoal. Efforts are under way to reforest the area with huarangos.

In the southwest of Ecuador, Prosopis pallida and Prosopis juliflora both display substantial genetic variability due to the (intraspecific) cross pollination of their self incompatible flowers which are typical of the genus Prosopis. As a result, trees of these species display a range of physical traits that lead to trees of one species resembling descriptions of the other, and the two species are often confused. To compound the difficulty in discerning the species of a given tree, these two species hybridise readily where their ranges overlap. In the semi arid Zapotillo Canton of Ecuador, both thorn bearing and thornless strains of Prosopis pallida exist with thorn bearing trees being more common. It is the preferred tree of the local people for making charcoal and is sometimes also cut for firewood or fence posts.

The first specimen in Hawaii was planted from a seed brought by missionary Alexis Bachelot from the Palais Royal Gardens in 1828.