DOWNHILL WALKWAY TO CITY
TREES OF NOTE

Walk details - click

A number of trees are indicated on the map. The following are brief notes on those trees with some items of general interest.

Path marked in PURPLE

Features marked in blue circle
and yellow letter

A. Bentham Cypress
B. Birch collection
C. Californian Redwood
D. Port Jackson Pine
E. Pohutukawa
F. Northern Rata and Ash collection
G. Araucaria and hydrangea collections
H. Peppermint Gum
I. Pinus torreyana
J. NZ Kauri

A: Cupressus lusitanica var. benthamii


The Mexican Cypress or Cedar of Goa is native to the mountains of western Mexico and Guatemala. It was introduced to Portugal by early travelers, where it is now quite common. (Portugal is Lusitanica in Latin).


In warm climates it grows quite vigorously but it will also tolerate cold and dry conditions. It is an excellent wind break and shelter tree and grows to 10 m (30 feet) or more in 15 years.

B Betula
Birches are common trees and shrubs of northern temperate and boreal zones of the Northern Hemisphere. The group is highly diversified, especially in the Old World. The species are well known for their free hybridisation, and specimens are therefore frequently difficult to identify.

Birches occupy habitats in cool, moist regions, including peat lands, stream banks, and lake shores, cool, damp woods, and moist slopes in cool coves.

The wood of species that grow to a large size has many uses, including the manufacture of doors and windows, flooring, cabinetry, interior moulding, wood paneling, furniture, and plywood.

Species number around 35 throughout Northern Hemisphere, North America, Asia.

Betula papyrifera the Paper Birch to the right towards the observatory, grows in woods, usually on slopes, edges of ponds, streams and swamps etc. Found in a wide range of soil conditions, but the best specimens are found in well-drained sandy-loam soils.

Native of Northern N. America to Greenland.

This species was an exceedingly important tree for the Indians - they utilised it for a very wide range of applications and it was a central item in their economy

The thin outer bark used to make drinking vessels, canoe skins, roofing tiles, buckets etc. This material was very widely used by various native North American Indian tribes; it is waterproof, durable, tough and resinous. Only the thin outer bark is removed, which does not kill the tree. It is most easily removed in late spring to early summer.

The outer bark has also been used as emergency sunglasses in order to prevent snow-blindness. A strip of bark 4 - 5 cm wide is placed over the eyes, the natural openings (lenticels) in the bark serving as apertures for the eyes.

A pioneer species, it rapidly invades deforested areas (such as after a forest fire or logging) and creates suitable conditions for other woodland trees to follow. Because it cannot grow or reproduce very successfully in the shade it is eventually out-competed by the other woodland trees. The tree has an extensive root system and can be planted to control banks from erosion.

The thin outer bark can be used as a paper substitute. It is carefully peeled off the tree and used as it is. A fibre is obtained from the inner bark and another from the heartwood; these are used in making paper. The branches of the tree can be harvested in spring or summer, the leaves and outer bark are removed, the branches are steamed and the fibers stripped off.

This tree has been removed because of extensive damage by Kaka, the native parrot
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C: Sequoia sempervirens
Called the Coast Redwood or California Redwood, it is native to the central and northern California coast. It grows in areas with mild climate with a humid climate. Summer moisture comes from fogs condensing on leaves, which also reduces plant evaporation. It grows 60 to 100 metres tall. Trees over 2000 years old have been identified. Redwood is one of the few vegetatively reproducing conifers, readily regenerating from stump sprouts in the wake of a major disturbance (typically fire).


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D: Callitris rhomboidea
The Port Jackson Pine or Oyster Bay Pine, sometimes called the Dune Cypress Pine, is native of Australia.

Its timber is used locally for building and poles, but is not plentiful enough to be of economic importance, and is sometimes used as a hedge plant in coastal or light soils. The timber of Callitris is resistant to termite attack, and is used for buildings and poles.

This is the most decorative of the native Australian cypresses.


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E: Metrosideros excelsa
At the time of European settlement the New Zealand Pohutukawa was confined to the coastal area of the North Island from the Three Kings Islands southwards to Poverty Bay and the east coast and around the mouth of the Urenui River on the west coast. It also grew around the shores of some of the Rotorua lakes. It has subsequently been extensively planted throughout the country.

It grows best close to the sea where its branches can overhang water. It likes to cling to steep banks with numerous roots extending from its lower branches, these aerial roots often seen even in cultivated plants on flat sites. Flowering in December and January, it produces a spectacular display. It is attractive out of flower. There are now a number of varieties.
Its wood is hard dense tough and durable, very strong and was much used in the early times in NZ for boat building. Its curved roots and branches made it possible to construct boats angled stems and keel from a single piece of timber. Also used for bearings, machine beds etc

Plants can be used as a hedge, succeeding in exposed maritime positions.

Can live for 1,000 years.

Pohutukawa Mac (McKenzie) Curator of the Garden from 1918 to 1947 was responsible for planting many in the garden.

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F: Metrosideros robusta.
The Northern Rata forms, when fully grown, one of the largest trees in the New Zealand forests.
The strong, tough, hard, and durable timber has been used for shipbuilding, but little rata finds its way to the commercial market nowadays.
This tree commences life from a seed lodged in the fork of almost any other large forest tree. It grows first as an epiphyte, then produces aerial roots which grow towards the ground. Clinging to the host tree trunk other roots encircle the trunk so that two or more aerial roots become connected by these side roots. In time the host tree is entwined and killed. The aerial root stems of the rata may ultimately fuse into a single enormous hollow trunk, which supports a huge canopy of branches and leaves. This in turn becomes infested with epiphytes such as astelias and ferns whose weight in time destroys it, thus bringing to an end a cycle of growth and decay covering several hundred years.
When the seed of the northern rata germinates on the ground it produces a stunted, twisted tree that never attains to the size of its true epiphytic form.
Decoctions of the bark, sap and the nectar of the flowers are all recorded as having medicinal uses

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Fraxinus - Ash
Related to the olives, it comprises some 65 species of deciduous trees and some shrubs scattered over the cool temperate parts of the Northern Hemisphere. There are a number of American ash species (not in Garden). A small collection can be found above the playground.

G: Araucaria genus
A genus of some 19 species, native of South America (Chile, Argentina and Brazil) and Australasia. The name Araucaria is derived from "Araucanos", the name of a tribe in Chile that inhabited the region where the first Araucaria was discovered.

Some species grow to 1,000 years old. Because of their large size, many are important sources of timber, and the fruit of A. bidwillii is an important food source of aboriginal peoples and are now an Australian delicacy.

Many of the tropical species, which are difficult to locate in the wild, are threatened with extinction especially with the rapid disappearance of their habitats.

This group includes
Araucaria araucana the Monkey Puzzle is native of Chile and Argentina. It grows 30-40 metres tall. It is able to survive fire with a thick bark and the ability to re-sprout from the trunk producing multiple shoots. It is long lived, possibly living over 1000 years.

Very tolerant of maritime exposure, trees can be grown as part of a shelter belt, though they are very slow growing and have an open canopy and so do not give a lot of shelter.

Araucaria columnaris
The New Caledonia Pine, Cook Pine or Coral Reef Araucaria is native of New Caledonia and the Loyalty Islands. It is a narrowly conical tree growing up to 60 metres tall.


Araucaria cunninghamii
The Hoop or Morton Bay Pine is native of coastal tropical and subtropical rain forest, in Australia from northern Queensland to Coffs Harbour in NSW. Growing up to 60 metres tall .its bark is heavily impregnated with resin, and is therefore much more resistant to decay than the wood of the other Araucarias. It grows on the drier sites in rain forests, in places that are rocky or have soils with relatively low fertility. It is not very frost-hardy. It is moderately drought resistant once it is established, but prefers a good summer rainfall. It grows very slowly and lives for up to 450 years. It can take over 200 years to produce cones.. As the bark ages, it splits horizontally at regular intervals giving the common name, hoop pine


It is widely distributed in Australia both as an ornamental and in timber plantations.

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Araucaria heterophylla

The Norfolk Island Pine, endemic to Norfolk Island, is widely grown in coastal areas of Australia and NZ because it is both salt-spray and wind tolerant, and able to grow in sandy soil. It is also drought tolerant, and grows rapidly to 30 m (100 feet).
Captain Cook thought this tree would provide masts for the largest ships, but it was found later to be unsuitable for this purpose. Its timber is used for other purposes. It is the Araucaria most used as an ornamental.
This tree is said to have been common in NZ during the Jurassic period some 150-200 million years ago.

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Hydrangea
Collection on Myrtle Way by araucarias

The name Hydrangea is Greek, meaning "water vessel". It is derived from the shape of its seed capsule.

This diverse group of plants contains roughly 23 different species. This group consists of hardy and tender shrubs and woody climbers. They are mostly deciduous plants, though a few of the tender species are evergreen. They are natives of the Himalayas, North and South America, and central and eastern Asia.

These flowering shrubs have different flower forms - from the large globes of the "mopheads" to the discs of the "lacecaps" to the thick cones of oakleaf and panicle hydrangeas. They come in an array of colours from pure white to brilliant crimson, pale lilac to intense azure. Some varieties produce blossoms with two-toned colours, while some flowers have contrasting eyes, and some may even be speckled or striped with another colour.
There are two kinds of florets in the flower heads. The sterile or ray florets are male and form the large, colourful sepals on the outside of the flower head. The fertile or perfect florets are small and inconspicuous. They bear the male and female parts and are usually found in the centre of the cluster.

The flower heads of mophead hydrangeas consist almost entirely of sterile florets. Besides for their lovely flowers, some hydrangeas are valued for their attractive foliage or bark. The sizes of the plants range from dwarf (about 3 ft. high) to large bushes with stems over 10 ft. high. There are also climbing hydrangeas whose aerial rootlets can bring stems up to 80 ft. high.

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H: Eucalyptus pulchella
Peppermint Gum, White Peppermint, Narrow-leaved Peppermint is found primarily in central and southeastern Tasmania, preferring moist, well-drained sites, but it is adaptable. Poor soils with low fertility suit it best. It is a good species for colder climates. It will grow to about 20-30m (up to 100 feet) tall, with an open habit.


It is extensively cultivated, and is used as a street tree. It has smooth bark throughout the tree, which is yellow to white to gray in colour. The bark is thin and finely fibrous, not stringy or furrowed. It peels off in fibrous sheets.

The leaves are peppermint-scented when crushed. It has white flowers in the summer and autumn.

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I: Pinus torreyana
Only two small natural stands of the Solidad or Torrey Pine exist. One, in Torrey Pines State Reserve, near La Jolla, north of San Diego, has about 7000 trees, and the other on Santa Rosa Island, 280 km away, off the coast of Santa Barbara, has about 2000 trees only.

It grows along sea cliffs, and tolerates drought, poor or sandy soil, and storms.

It is the rarest native pine in the United States.

Plants were first planted in the Garden in June 1871, with seed purchased that year. Over the years 1871/72 73 were planted.

Wood - light, soft, brittle and rots easily.

The Torrey Pine has very large, edible, though very hard, seeds that are used as an indigenous food source by local Indians.

Succulent Garden just before the Treehouse Information Centre

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J: Agathis australis


Kauri is probably the most famous of our native trees and one of the largest in the world. Tane Mahuta, the famous tree in Waipoua Forest, is over 50 m (160 feet) high and has been calculated to be over 2,100 years old. Even larger trees, over 60 m (180 feet) high and 7 m (22 feet) in diameter are known. Today only about 142 hectares (355 acres) of Kauai forest remain, and the trees average about 30 m (100 feet) in height

Kauri timber is light and very durable, straight grained and free of knots, and easily worked. It has had many building uses in the past but today is a scarce resource.

Maori used Kauai for the construction of war canoes.

Kauri trees also produced gum, known internationally as Manila copal. This material was a valuable constituent of varnishes and when mixed with linseed, was used widely in the manufacture of linoleum. It is still used for specialised uses such as varnishes for labels on food cans, for colour prints, and as an ingredient in the paint used to paint lines on roads. Production of gum reached a peak in 1905 and ceased in 1950. Subsoil fragments of gum are sometimes gathered and polished with lovely results.

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The Downhill Walk is discussed in a number of sections.

Starting at the Cable Car :

Details
Introduction
Walk 1 Grass Way
Walk 2 Main Garden
Walk 3 Rose Garden and Begonia House
Walk 4 Bolton Street Memorial Park

Other walks

Walk 5 East Way and Norwood Path
Walk 6 Kowhai Walk

Walk 7 Sculptures

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