New Zealand Christmas bush

Description

Metrosideros kermadecensis, with common names Kermadec pōhutukawa and New Zealand Christmas bush is an evergreen tree of the myrtle family which is endemic to the volcanic Kermadec Islands about 900 km north-east of New Zealand. The tree produces a brilliant display of red flowers, made up of a mass of stamens and is the dominant forest tree on Raoul Island, growing to 15 m or more. The trunk is up to 1 m or more in diameter. It is very similar to, and often confused with, the pōhutukawa of mainland New Zealand, differing mainly by having smaller, more oval leaves, and by flowering throughout the year. It also resembles the ʻōhiʻa lehua of Hawaiʻi. Because it is endemic to a small group of islands, Metrosideros kermadecensis is listed as range restricted, but is not regarded as threatened. Metrosideros kermadecensis is widely cultivated in New Zealand and has naturalised in Hawaiʻi. A variegated form is widely planted in home gardens. Propagation is easy from fresh seed. Cuttings may be grown from water shoots. It hybridises with pōhutukawa (M. excelsa). Metrosideros is one of the most widely spread flowering plant genera in the Pacific. New Caledonia has 21 species of Metrosideros, New Zealand has 12, New Guinea has seven and Hawaii has 5. The genus is present on most other high Pacific Islands, including Solomon Islands, Vanuatu, Fiji, Samoa, Cook islands, French Polynesia, Bonin Islands and Lord Howe Island, but absent from Micronesia. The genus is also represented by one species in the Philippines, one in South America (Chile and Argentina), and one outlier in South Africa. Metrosideros seeds are very lightweight and easily dispersed by wind. The seeds can also survive freezing temperatures, and up to 30 days submerged in salt water and still germinate. which probably accounts for their wide distribution. They are often found as pioneer trees on lava flows and on mountain ridges. Despite the clear propensity towards long-distance dispersal, this genus does not occur in mainland Australia.