''Metrosideros umbellata'', the southern rātā, is a tree endemic to
New Zealand
New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...
. It grows up to or more tall with a trunk up to or more in diameter. It produces masses of red flowers in summer. Unlike its relative,
northern rātā
''Metrosideros robusta'', the northern rātā, is a forest tree endemic to New Zealand. It grows up to or taller, and usually begins its life as a hemiepiphyte high in the branches of a mature forest tree; over centuries the young tree sends d ...
, this species rarely grows as an
epiphyte
An epiphyte is an organism that grows on the surface of a plant and derives its moisture and nutrients from the air, rain, water (in marine environments) or from debris accumulating around it. The plants on which epiphytes grow are called phoroph ...
.
Description
The flowers of southern rātā are scarlet, with stamens about long. White or yellow flowers are also known. Flowering usually occurs between December and February, but this depends on local conditions. Leaves are from to long, and are sharply pointed. The wood is hard, dense, and very strong. The bark is rough and flaky and provides an ideal stratum for the roots of epiphytic plants such as ''
Astelia
''Astelia'' is a genus of flowering plants in the recently named family Asteliaceae. They are rhizomatous tufted perennials native to various islands in the Pacific, Indian, and South Atlantic Oceans, as well as to Australia and to the southern ...
'' species and
Freycinetia banksii (Kiekie). Southern rātā is a major source of honey on the West Coast of the South Island.
Kaka,
tui, and
bellbirds visit rātā to take advantage of the abundant nectar.
Distribution
It prefers cooler regions with high rainfall and is particularly common along the west coast of the
South Island
The South Island, also officially named , is the larger of the two major islands of New Zealand in surface area, the other being the smaller but more populous North Island. It is bordered to the north by Cook Strait, to the west by the Tasman ...
where its nectar is the main source of a locally produced rātā honey. Southern rātā is the most widespread of the New Zealand tree rātā species. It is locally present in the
North Island
The North Island, also officially named Te Ika-a-Māui, is one of the two main islands of New Zealand, separated from the larger but much less populous South Island by the Cook Strait. The island's area is , making it the world's 14th-largest ...
from latitude 36° southwards, is more common in western parts of the
South Island
The South Island, also officially named , is the larger of the two major islands of New Zealand in surface area, the other being the smaller but more populous North Island. It is bordered to the north by Cook Strait, to the west by the Tasman ...
but absent from much of the east, and is common on
Stewart Island
Stewart Island ( mi, Rakiura, ' glowing skies', officially Stewart Island / Rakiura) is New Zealand's third-largest island, located south of the South Island, across the Foveaux Strait. It is a roughly triangular island with a total land ar ...
(47°S) and in the
Auckland Islands
The Auckland Islands (Māori: ''Motu Maha'' "Many islands" or ''Maungahuka'' "Snowy mountains") are an archipelago of New Zealand, lying south of the South Island. The main Auckland Island, occupying , is surrounded by smaller Adams Island, ...
, where it reaches its southern limit at just over 50°S.
Conservation
Although southern rātā is not regarded as threatened, it is rather uncommon in the North Island, and in certain areas it is threatened by possum browse. In the Tararua range, southern rātā populations appear to have been replaced by a population consisting of hybrids between northern and southern rātā.
Project Crimson
__NOTOC__
Project Crimson is a conservation initiative to promote the protection of the metrosideros excelsa, pōhutukawa and the Metrosideros, rātā which are under threat due to browsing by the introduced common brushtail possum. The vision of ...
is a charitable trust that promotes conservation of rātā as well as the related
pōhutukawa
''Metrosideros excelsa'', commonly known as pōhutukawa ( mi, pōhutukawa), New Zealand Christmas tree, New Zealand Christmas bush, and iron tree, is a coastal evergreen tree in the myrtle family, Myrtaceae, that produces a brilliant display o ...
.
Cultivation
Southern rātā is a beautiful specimen tree, but growth can be slow unless it is grown in ideal conditions with moist soil. It is easily grown from fresh seed. While it is possible to grow the tree from softwood or semi-hardwood cuttings, these often prove reluctant to strike roots. It is ideal for coastal environments because it has a good resistance to wind and salt.
At least 16
cultivar
A cultivar is a type of cultivated plant that people have selected for desired traits and when propagated retain those traits. Methods used to propagate cultivars include: division, root and stem cuttings, offsets, grafting, tissue culture, ...
s of southern rātā have been released.
There are also known cultivars of hybrids between southern rātā and pōhutukawa, and between northern rātā and southern rātā.
Known cultivars include:
∞ Hybrid of southern rātā and northern rātā
¤ Hybrid of southern rātā and pōhutukawa
See also
*''
Metrosideros excelsa
''Metrosideros excelsa'', commonly known as pōhutukawa ( mi, pōhutukawa), New Zealand Christmas tree, New Zealand Christmas bush, and iron tree, is a coastal evergreen tree in the Myrtus, myrtle family, Myrtaceae, that produces a brilliant di ...
'', pōhutukawa
*''
Metrosideros robusta
''Metrosideros robusta'', the northern rātā, is a forest tree endemic to New Zealand. It grows up to or taller, and usually begins its life as a hemiepiphyte high in the branches of a mature forest tree; over centuries the young tree sends d ...
'', northern rātā
*''
Metrosideros bartlettii
''Metrosideros bartlettii'', also known as Bartlett's rātā, Cape Reinga white rātā or in Māori as rātā moehau, is one of twelve ''Metrosideros'' species endemic to New Zealand and is notable for its extreme rarity and its white flowers, s ...
'', Bartlett's rātā
*''
Metrosideros parkinsonii
''Metrosideros parkinsonii'', also known as Parkinson's rātā or shrubby rata, is a shrub or small tree endemic to New Zealand. The name commemorates Sydney Parkinson, Captain James Cook's botanical artist during his first voyage to New Zealan ...
'', Parkinson's rātā
References
*
*
*
Further reading
*Salmon, J.T., 1986. ''The Native Trees of New Zealand''. Wellington: Heinneman Reed.
*Simpson, P., 2005. ''Pōhutukawa & Rātā: New Zealand's Iron-Hearted Trees''. Wellington: Te Papa Press.
External links
Project Crimson
{{Taxonbar, from=Q1461888
umbellata
Endemic flora of New Zealand
Flora of the Auckland Islands
Trees of New Zealand
Trees of mild maritime climate
Garden plants of New Zealand
Ornamental trees
Taxa named by Antonio José Cavanilles