Madagascar palm

Description

Pachypodium rutenbergianum is a species of Pachypodium native to Madagascar. The plant can reach 3 to 8 m high, and its trunk up to 60 cm in diameter at base. The plant has short branches and 1-cm long spines. Leaves are green and 10 to 15 cm long, 4 cm wide. Its flowers are white. Pachypodium is a genus of succulent spine-bearing trees and shrubs, native to Madagascar and Africa. It belongs to the family Apocynaceae. Pachypodium are native to Madagascar and continental Southern Africa, i.e. Angola, Zaire, Botswana, Mozambique, Namibia, South Africa, Eswatini and Zimbabwe. In elevation, Pachypodium in both mainland Africa and Madagascar grow between an altitude of sea level, where some species grow in sand dunes, such as Pachypodium geayi, to 1,600 m (5,200 ft) for Pachypodium lealii in southern Africa and 1,900 m (6,200 ft) for Pachypodium brevicaule in Madagascar. In continental southern Africa, the extreme temperatures range from −10 °C (14 °F) in some locations to as much as 45 °C (113 °F). Whereas in Madagascar, with not such a great temperature amplitude, the temperature ranges from −6 to 40 °C (21 to 104 °F). A generalization about precipitation regimes for both southern Africa and Madagascar does not have much meaning because the habitats of Pachypodium vary so greatly with a moisture regime. In some places, Pachypodium receive annually from as little as 75 mm (3.0 in) from the southern part of Africa to a high level of 1,985 mm (78.1 in). A precipitation regime for a species of Pachypodium, therefore, depends upon a habitat's location relative to the influences of the Atlantic and Indian Oceans and the various mountain ranges of southern continental Africa and of Madagascar. The genus grows in areas where there are significant periods of dry months that range from five months to ten months. It would seem likely that the Atlantic and India Oceans pay a major role in the creation of weather conducive to rainfall, not to mention mountain ranges. For example, the Madagascar dry deciduous forests with their long dry season and severe limestone ridden soils provide one ideal setting for pachypodium. Pachypodium grows in various types of substrates. Some species only grow in one substrate whereas other will grow in several. The degree to which a taxon can grow in a given substrate seems to determine how specialized its habitat is within the landscape and climates.