Dacrydium cupressinum
Encyclopedia
Dacrydium cupressinum, commonly known as rimu, is a large evergreen
coniferous
tree
endemic to the forests of New Zealand
. It is a member of the southern conifer group, the podocarps. The former name "red pine" has fallen out of common use.
, South Island
and Stewart Island/Rakiura
. Although the largest concentration of trees is now found on the West Coast of the South Island, the biggest trees tend to be in mixed podocarp forest near Taupo
(e.g., Pureora, Waihaha, and Whirinaki Forests). A typical North Island habitat is in the Hamilton Ecological District
, where Nothofagus truncata
and rimu form the overstory. Associate ferns on the forest floor are Blechnum discolor
, Blechnum filiforme
, Asplenium flaccidum
and Hymenophyllum demissum
.
). There are historical accounts of exceptionally tall trees, 61 m, from dense forest near National Park, New Zealand
, now destroyed. Its lifespan is approximately 800 to 900 years. The straight trunk of the rimu is generally 1.5 m in diameter, but may be larger in old or very tall specimens.
The leaves
are spirally arranged, awl-shaped, up to 7 mm long on juvenile plants, and 1 mm wide; and 2 to 3 mm long on mature trees. It is dioecious
, with male and female cones
on separate trees; the seeds take 15 months to mature after pollination
. The mature cones comprise a swollen red fleshy scale six to ten mm long bearing one (rarely two) apical seed
s 4 mm long. The seeds are dispersed by bird
s which eat the fleshy scale and pass the seed on in their droppings; they are an important food resource for some species, particularly the kakapo
, whose breeding cycle has been linked to cone production cycle of the tree.
were the main sources of wood
for New Zealand, including furniture
and house
construction. However, many of New Zealand's original stands of rimu have been destroyed, and recent government policies forbid the felling of rimu in public forests, though allowing limited logging on private land. Pinus radiata has now replaced rimu in most industries, although rimu remains popular for the production of high quality wooden furniture. There is also limited recovery of stump and root wood, from trees felled many years before, for use in making bowls and other wood turned objects.
The inner bark can also be used to treat burns and cuts.
There is only one cultivated variety called Charisma (rimu)
Evergreen
In botany, an evergreen plant is a plant that has leaves in all seasons. This contrasts with deciduous plants, which completely lose their foliage during the winter or dry season.There are many different kinds of evergreen plants, both trees and shrubs...
coniferous
Pinophyta
The conifers, division Pinophyta, also known as division Coniferophyta or Coniferae, are one of 13 or 14 division level taxa within the Kingdom Plantae. Pinophytes are gymnosperms. They are cone-bearing seed plants with vascular tissue; all extant conifers are woody plants, the great majority being...
tree
Tree
A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...
endemic to the forests of New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
. It is a member of the southern conifer group, the podocarps. The former name "red pine" has fallen out of common use.
Distribution
Rimu grows throughout New Zealand, in the North IslandNorth Island
The North Island is one of the two main islands of New Zealand, separated from the much less populous South Island by Cook Strait. The island is in area, making it the world's 14th-largest island...
, South Island
South Island
The South Island is the larger of the two major islands of New Zealand, the other being the more populous North Island. It is bordered to the north by Cook Strait, to the west by the Tasman Sea, to the south and east by the Pacific Ocean...
and Stewart Island/Rakiura
Stewart Island/Rakiura
Stewart Island/Rakiura is the third-largest island of New Zealand. It lies south of the South Island, across Foveaux Strait. Its permanent population is slightly over 400 people, most of whom live in the settlement of Oban.- History and naming :...
. Although the largest concentration of trees is now found on the West Coast of the South Island, the biggest trees tend to be in mixed podocarp forest near Taupo
Taupo
Taupo is a town on the shore of Lake Taupo in the centre of the North Island of New Zealand. It is the seat of the Taupo District Council and lies in the southern Waikato Region....
(e.g., Pureora, Waihaha, and Whirinaki Forests). A typical North Island habitat is in the Hamilton Ecological District
Hamilton Ecological District
Hamilton Ecological District is part of the Waikato Ecological Region in New Zealand's North Island. It occupies the Hamilton basin and surrounding foothills, and has been heavily modified with less than two percent of its indigenous vegetation remaining. This location has been studied...
, where Nothofagus truncata
Nothofagus truncata
Nothofagus truncata or Hard Beech is a species of tree endemic to New Zealand. Its common name derives from the fact that its wood has a high silica content, making it hard and difficult to saw. Hard Beech is a tree up to 30m tall occurring in lowland and lower montane forest from lat...
and rimu form the overstory. Associate ferns on the forest floor are Blechnum discolor
Blechnum discolor
Blechnum discolor is a species of fern in the family Blechnaceae. This species is endemic to New Zealand. As noted by C. Michael Hogan, this species is found in a number of forest communities in diverse locations within New Zealand, and is sometimes a dominant understory component.Spores are...
, Blechnum filiforme
Blechnum filiforme
Blechnum filiforme or thread fern is an endemic New Zealand fern species in the hard fern family, Blechnaceae. The species authority is Ettingsh.Thread fern has a creeping and climbing habit...
, Asplenium flaccidum
Asplenium flaccidum
Asplenium flaccidum is a species of fern in the family Aspleniaceae. The plant common name is Drooping Spleenwort or Weeping Spleenwort, and the species name flaccidum derives from the Latin root meaning drooping. An example occurrence of A...
and Hymenophyllum demissum
Hymenophyllum demissum
Hymenophyllum demissum is a species of fern in the family Hymenophyllaceae. H. demissum is found in New Zealand, with a specific example occurrence being in North Island's Hamilton Ecological District in a Nothofagus-podocarp forest in association with other fern species understory plants, Crown...
.
Description
Rimu is a slow-growing tree, eventually attaining a height of up to 50 m, although most surviving large trees are 20 to 35 m tall. It typically appears as an emergent from mixed broadleaf temperate rainforest, although there are almost pure stands (especially the west coast of the South IslandSouth Island
The South Island is the larger of the two major islands of New Zealand, the other being the more populous North Island. It is bordered to the north by Cook Strait, to the west by the Tasman Sea, to the south and east by the Pacific Ocean...
). There are historical accounts of exceptionally tall trees, 61 m, from dense forest near National Park, New Zealand
National Park, New Zealand
National Park is a small town on the central plateau of the North Island of New Zealand. Also known as National Park Village it is the highest urban township in New Zealand at 825 metres. As the name suggests, it borders the World Heritage Tongariro National Park, New Zealand's first national...
, now destroyed. Its lifespan is approximately 800 to 900 years. The straight trunk of the rimu is generally 1.5 m in diameter, but may be larger in old or very tall specimens.
The leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
are spirally arranged, awl-shaped, up to 7 mm long on juvenile plants, and 1 mm wide; and 2 to 3 mm long on mature trees. It is dioecious
Plant sexuality
Plant sexuality covers the wide variety of sexual reproduction systems found across the plant kingdom. This article describes morphological aspects of sexual reproduction of plants....
, with male and female cones
Conifer cone
A cone is an organ on plants in the division Pinophyta that contains the reproductive structures. The familiar woody cone is the female cone, which produces seeds. The male cones, which produce pollen, are usually herbaceous and much less conspicuous even at full maturity...
on separate trees; the seeds take 15 months to mature after pollination
Pollination
Pollination is the process by which pollen is transferred in plants, thereby enabling fertilisation and sexual reproduction. Pollen grains transport the male gametes to where the female gamete are contained within the carpel; in gymnosperms the pollen is directly applied to the ovule itself...
. The mature cones comprise a swollen red fleshy scale six to ten mm long bearing one (rarely two) apical seed
Seed
A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...
s 4 mm long. The seeds are dispersed by bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
s which eat the fleshy scale and pass the seed on in their droppings; they are an important food resource for some species, particularly the kakapo
Kakapo
The Kakapo , Strigops habroptila , also called owl parrot, is a species of large, flightless nocturnal parrot endemic to New Zealand...
, whose breeding cycle has been linked to cone production cycle of the tree.
Uses
Historically, rimu and other native trees such as kauri and totaraPodocarpus totara
Podocarpus totara is a species of podocarp tree endemic to New Zealand. It grows throughout the North Island and northeastern South Island in lowland, montane and lower subalpine forest at elevations of up to 600 m.-Description:...
were the main sources of wood
Wood
Wood is a hard, fibrous tissue found in many trees. It has been used for hundreds of thousands of years for both fuel and as a construction material. It is an organic material, a natural composite of cellulose fibers embedded in a matrix of lignin which resists compression...
for New Zealand, including furniture
Furniture
Furniture is the mass noun for the movable objects intended to support various human activities such as seating and sleeping in beds, to hold objects at a convenient height for work using horizontal surfaces above the ground, or to store things...
and house
House
A house is a building or structure that has the ability to be occupied for dwelling by human beings or other creatures. The term house includes many kinds of different dwellings ranging from rudimentary huts of nomadic tribes to free standing individual structures...
construction. However, many of New Zealand's original stands of rimu have been destroyed, and recent government policies forbid the felling of rimu in public forests, though allowing limited logging on private land. Pinus radiata has now replaced rimu in most industries, although rimu remains popular for the production of high quality wooden furniture. There is also limited recovery of stump and root wood, from trees felled many years before, for use in making bowls and other wood turned objects.
The inner bark can also be used to treat burns and cuts.
There is only one cultivated variety called Charisma (rimu)